Transmission of energy or mass by a medium involving movement of the medium itself. The circulatory movement that occurs in a fluid at a nonuniform temperature owing to the variation of its density and the action of gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed; Webster, 10th ed)
The heat flow across a surface per unit area per unit time, divided by the negative of the rate of change of temperature with distance in a direction perpendicular to the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The motion of air currents.
The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.
The apparent deflection (Coriolis acceleration) of a body in motion with respect to the earth, as seen by an observer on the earth, attributed to a fictitious force (Coriolis force) but actually caused by the rotation of the earth. In a medical context it refers to the physiological effects (nausea, vertigo, dizziness, etc.) felt by a person moving radially in a rotating system, as a rotating space station. (From Random House Unabridged Dictionary, 2d ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The motion of fluids, especially noncompressible liquids, under the influence of internal and external forces.
The combination of hemodialysis and hemofiltration either simultaneously or sequentially. Convective transport (hemofiltration) may be better for removal of larger molecular weight substances and diffusive transport (hemodialysis) for smaller molecular weight solutes.
The gaseous envelope surrounding a planet or similar body. (From Random House Unabridged Dictionary, 2d ed)
The study of the deformation and flow of matter, usually liquids or fluids, and of the plastic flow of solids. The concept covers consistency, dilatancy, liquefaction, resistance to flow, shearing, thixotrophy, and VISCOSITY.
The processes of diffusion across the BLOOD-AIR BARRIER, and the chemical reactions coupled with diffusion that effect the rate of PULMONARY GAS EXCHANGE, generally at the alveolar level.
Cationic bactericidal surfactant used as a topical antiseptic for skin, wounds, mucous membranes, instruments, etc.; and also as a component in mouthwash and lozenges.
Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
The fluid of the body that is outside of CELLS. It is the external environment for the cells.
The application of heat to raise the temperature of the environment, ambient or local, or the systems for accomplishing this effect. It is distinguished from HEAT, the physical property and principle of physics.
A genus in the family ORTHOMYXOVIRIDAE causing influenza and other diseases in humans and animals. It contains many strains as well as antigenic subtypes of the integral membrane proteins hemagglutinin (HEMAGGLUTININS) and NEURAMINIDASE. The type species is INFLUENZA A VIRUS.
A technique for the treatment of neoplasms, especially gliomas and melanomas in which boron-10, an isotope, is introduced into the target cells followed by irradiation with thermal neutrons.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
Extracorporeal ULTRAFILTRATION technique without HEMODIALYSIS for treatment of fluid overload and electrolyte disturbances affecting renal, cardiac, or pulmonary function.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.
The pressure due to the weight of fluid.
The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.
The processes of heating and cooling that an organism uses to control its temperature.
Methods utilizing the principles of MICROFLUIDICS for sample handling, reagent mixing, and separation and detection of specific components in fluids.
Presence of warmth or heat or a temperature notably higher than an accustomed norm.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A contagious disease caused by canine adenovirus (ADENOVIRUSES, CANINE) infecting the LIVER, the EYE, the KIDNEY, and other organs in dogs, other canids, and bears. Symptoms include FEVER; EDEMA; VOMITING; and DIARRHEA.
Diseases of the domestic dog (Canis familiaris). This term does not include diseases of wild dogs, WOLVES; FOXES; and other Canidae for which the heading CARNIVORA is used.
Systems for the delivery of drugs to target sites of pharmacological actions. Technologies employed include those concerning drug preparation, route of administration, site targeting, metabolism, and toxicity.
The administration of medication or fluid directly into localized lesions, by means of gravity flow or INFUSION PUMPS.
Fluid propulsion systems driven mechanically, electrically, or osmotically that are used to inject (or infuse) over time agents into a patient or experimental animal; used routinely in hospitals to maintain a patent intravenous line, to administer antineoplastic agents and other drugs in thromboembolism, heart disease, diabetes mellitus (INSULIN INFUSION SYSTEMS is also available), and other disorders.
Gadolinium. An element of the rare earth family of metals. It has the atomic symbol Gd, atomic number 64, and atomic weight 157.25. Its oxide is used in the control rods of some nuclear reactors.
Implanted fluid propulsion systems with self-contained power source for providing long-term controlled-rate delivery of drugs such as chemotherapeutic agents or analgesics. Delivery rate may be externally controlled or osmotically or peristatically controlled with the aid of transcutaneous monitoring.
A mutant strain of Rattus norvegicus without a thymus and with depressed or absent T-cell function. This strain of rats may have a small amount of hair at times, but then lose it.
Any type of variation in the appearance of energy output of the sun. (NASA Thesaurus, 1994)
An independent Federal agency established in 1958. It conducts research for the solution of problems of flight within and outside the Earth's atmosphere and develops, constructs, tests, and operates aeronautical and space vehicles. (From U.S. Government Manual, 1993)
The exchange or transmission of ideas, attitudes, or beliefs between individuals or groups.
Travel beyond the earth's atmosphere.
Members of spacecraft crew including those who travel in space, and those in training for space flight. (From Webster, 10th ed; Jane's Aerospace Dictionary, 3d ed)
High-energy radiation or particles from extraterrestrial space that strike the earth, its atmosphere, or spacecraft and may create secondary radiation as a result of collisions with the atmosphere or spacecraft.

Acinar flow irreversibility caused by perturbations in reversible alveolar wall motion. (1/141)

Mixing associated with "stretch-and-fold" convective flow patterns has recently been demonstrated to play a potentially important role in aerosol transport and deposition deep in the lung (J. P. Butler and A. Tsuda. J. Appl. Physiol. 83: 800-809, 1997), but the origin of this potent mechanism is not well characterized. In this study we hypothesized that even a small degree of asynchrony in otherwise reversible alveolar wall motion is sufficient to cause flow irreversibility and stretch-and-fold convective mixing. We tested this hypothesis using a large-scale acinar model consisting of a T-shaped junction of three short, straight, square ducts. The model was filled with silicone oil, and alveolar wall motion was simulated by pistons in two of the ducts. The pistons were driven to generate a low-Reynolds-number cyclic flow with a small amount of asynchrony in boundary motion adjusted to match the degree of geometric (as distinguished from pressure-volume) hysteresis found in rabbit lungs (H. Miki, J. P. Butler, R. A. Rogers, and J. Lehr. J. Appl. Physiol. 75: 1630-1636, 1993). Tracer dye was introduced into the system, and its motion was monitored. The results showed that even a slight asynchrony in boundary motion leads to flow irreversibility with complicated swirling tracer patterns. Importantly, the kinematic irreversibility resulted in stretching of the tracer with narrowing of the separation between adjacent tracer lines, and when the cycle-by-cycle narrowing of lateral distance reached the slowly growing diffusion distance of the tracer, mixing abruptly took place. This coupling of evolving convective flow patterns with diffusion is the essence of the stretch-and-fold mechanism. We conclude that even a small degree of boundary asynchrony can give rise to stretch-and-fold convective mixing, thereby leading to transport and deposition of fine and ultrafine aerosol particles deep in the lung.  (+info)

Cytoplasmic transport of fatty acids in rat enterocytes: role of binding to fatty acid-binding protein. (2/141)

The intracellular movement of fatty acids is thought to be facilitated through codiffusion with fatty acid-binding protein (FABP). This facilitation may occur by decreasing binding to immobile membranes, leading to faster cytoplasmic diffusion. The aims of this study were to measure the intracellular transport of 12-N-methyl-(7-nitrobenzo-2-oxa-1,3-diazol)aminostearate (NBD-stearate) in villus rat enterocytes and to determine 1) the mechanism of its cytoplasmic transport and 2) if its transport rate correlated with the known variation of FABP binding capacity along the length of the small intestine. Two-dimensional laser photobleaching was used to measure the movement of a fluorescent fatty acid NBD-stearate in enterocytes isolated from different segments of rat intestine. The fraction of NBD-stearate found in the cytostol of enterocytes was determined by differential centrifugation. Cytoplasmic transport of NBD-stearate occurred solely by diffusion and not by convection. Diffusion was homogeneous (nondirectional), consistent with isotropic diffusion. The diffusion rate varied with location along the intestine, correlating with the local FABP concentration and measured cytosolic binding. We conclude that cytoplasmic proteins like FABP promote the intracellular transport of fatty acids by enhancing their diffusive flux. We suggest that facilitation is not specific for a particular cell type but occurs in a variety of cells that transport fatty acids and may contain different types of FABP.  (+info)

Clothing convective heat exchange--proposal for improved prediction in standards and models. (3/141)

Convection is an important determinant for both sensible and evaporative heat exchange. Heat transfer by convection for normal boundary conditions is readily described by simple power functions. Clothing affects convection in various ways and existing characterisation of clothing by its static insulation values produces inaccurate prediction of sensible heat exchange, eventually leading to erroneous risk assessment. The present paper reviews various methods for evaluation of clothing convective (sensible) heat exchange. Based on available data, two equations are proposed for determination of the reduction of the total insulation values obtained under static, still wind conditions as a consequence of wind and walking effects. The equations apply from 0 to 1.84 clo, from 0.2 to 3 m/s and for walking speeds up to 1.2 m/s. The equations are incorporated in ISO 7933 to provide a more realistic and accurate prediction of sensible heat transfer through clothing.  (+info)

The effects of wind and human movement on the heat and vapour transfer properties of clothing. (4/141)

This paper integrates the research presented in the papers in this special issue of Holmer et al. and Havenith et al. [Holmer, I., Nilsson, H., Havenith, G., Parsons, K. C. (1999) Clothing convective heat exchange: proposal for improved prediction in standards and models. Annals of Occupational Hygiene, in press; Havenith, G., Holmer, I., den Hartog, E. and Parsons, K. C. (1999) Clothing evaporative heat resistance: proposal for improved representation in standards and models. Annals of Occupational Hygiene, in press] to provide a practical suggestion for improving existing clothing models so that they can account for the effects of wind and human movement. The proposed method is presented and described in the form of a BASIC computer program. Analytical methods (for example ISO 7933) for the assessment of the thermal strain caused by human exposure to hot environments require a mathematical quantification of the thermal properties of clothing. These effects are usually considered in terms of 'dry' thermal insulation and vapour resistance. This simple 'model' of clothing can account for the insulation properties of clothing which reduce heat loss (or gain) between the body and the environment and, for example, the resistance to the transfer of evaporated sweat from the skin, which is important for cooling the body in a hot environment. When a clothed person is exposed to wind, however, and when the person is active, there is a potentially significant limitation in the simple model of clothing presented above. Heat and mass transfer can take place between the microclimate (within clothing and next to the skin surface) and the external environment. The method described in this paper 'corrects' static values of clothing properties to provide dynamic values that take account of wind and human movement. It therefore allows a more complete representation of the effects of clothing on the heat strain of workers.  (+info)

Efficacy of two methods for reducing postbypass afterdrop. (5/141)

BACKGROUND: Afterdrop, defined as the precipitous reduction in core temperature after cardiopulmonary bypass, results from redistribution of body heat to inadequately warmed peripheral tissues. The authors tested two methods of ameliorating afterdrop: (1) forced-air warming of peripheral tissues and (2) nitroprusside-induced vasodilation. METHODS: Patients were cooled during cardiopulmonary bypass to approximately 32 degrees C and subsequently rewarmed to a nasopharyngeal temperature near 37 degrees C and a rectal temperature near 36 degrees C. Patients in the forced-air protocol (n = 20) were assigned randomly to forced-air warming or passive insulation on the legs. Active heating started with rewarming while undergoing bypass and was continued for the remainder of surgery. Patients in the nitroprusside protocol (n = 30) were assigned randomly to either a control group or sodium nitroprusside administration. Pump flow during rewarming was maintained at 2.5 l x m(-2) x min(-1) in the control patients and at 3.0 l x m(-2) x min(-1) in those assigned to sodium nitroprusside. Sodium nitroprusside was titrated to maintain a mean arterial pressure near 60 mm Hg. In all cases, a nasopharyngeal probe evaluated core (trunk and head) temperature and heat content. Peripheral compartment (arm and leg) temperature and heat content were estimated using fourth-order regressions and integration over volume from 18 intramuscular needle thermocouples, nine skin temperatures, and "deep" hand and foot temperature. RESULTS: In patients warmed with forced air, peripheral tissue temperature was higher at the end of warming and remained higher until the end of surgery. The core temperature afterdrop was reduced from 1.2+/-0.2 degrees C to 0.5+/-0.2 degrees C by forced-air warming. The duration of afterdrop also was reduced, from 50+/-11 to 27+/-14 min. In the nitroprusside group, a rectal temperature of 36 degrees C was reached after 30+/-7 min of rewarming. This was only slightly faster than the 40+/-13 min necessary in the control group. The afterdrop was 0.8+/-0.3 degrees C with nitroprusside and lasted 34+/-10 min which was similar to the 1.1+/-0.3 degrees C afterdrop that lasted 44+/-13 min in the control group. CONCLUSIONS: Cutaneous warming reduced the core temperature afterdrop by 60%. However, heat-balance data indicate that this reduction resulted primarily because forced-air heating prevented the typical decrease in body heat content after discontinuation of bypass, rather than by reducing redistribution. Nitroprusside administration slightly increased peripheral tissue temperature and heat content at the end of rewarming. However, the core-to-peripheral temperature gradient was low in both groups. Consequently, there was little redistribution in either case.  (+info)

Influence of convection on small molecule clearances in online hemodiafiltration. (6/141)

BACKGROUND: Dialysis efficacy is mostly influenced by dialyzer clearance. Urea clearance may be estimated in vitro by total ion clearance, which can be obtained by conductivity measurements. We have previously used this approach to assess in vitro clearances in a system mimicking predilutional and postdilutional online hemodiafiltration with a wide range of QD, QB, and ultrafiltration rates. Our current study elaborates on a formula that allows the prediction of the influence of ultrafiltration on small molecule clearances, and validates the mathematical approach both experimentally in vitro and clinically in vivo data. METHODS: Two conductivimeters in the dialysate side of an E-2008 Fresenius machine were used. HF80 and HF40 polysulfone dialyzers were used; reverse osmosis water and dialysate were used for blood and dialysate compartments, respectively. Study conditions included QB of 300 and 400 mL/min and QD of 500 and 590 mL/min, with a range of ultrafiltration rate from 0 to 400 mL/min in postdilutional hemodiafiltration and to 590 mL/min in predilutional hemodiafiltration. Urea clearances were determined in the in vivo studies, which included 0, 50, 100, and 150 mL/min ultrafiltration rates. RESULTS: The ultrafiltration rate and clearance were significantly correlated (R > 0.9, P < 0.001) and fitted a linear model (P < 0.001) in all of the experimental conditions. The following formula fitted the experimental points with an error <2% for both postdilutional and predilutional online diafiltration in vitro, respectively. K = K0 + [(QB - K0)/(QB)] x ultrafiltration rateK = K0 + [((QD x QB)/(QB + QD) - K0)/QD] x ultrafiltration rate where K is the clearance; K0 is the clearance with nil ultrafiltration rate; QD is the total dialysate produced (in commercial HDF, QD = QDi + Qinf). Since weight loss was maintained at 0, ultrafiltration rate = infusion flow. QB is the "blood" line flow. The formula was also verified in vivo in clinical postdilutional hemodiafiltration with a QB taking into account the cellular and water compartments. DISCUSSION: In vitro, by simply determining the clearance in conventional dialysis, the total clearance for any ultrafiltration rate may be estimated in both predilutional and postdilutional online diafiltration with an error of less than 2%. The same applies to in vivo postdilutional hemodiafiltration when the formula takes into account the cellular and water composition of blood.  (+info)

Contaminant dispersion in the vicinity of a worker in a uniform velocity field. (7/141)

The transportation of gaseous contaminant from a low and moderate low impulse (momentum<1 m s(-1)) source to the breathing zone was studied in a uniform air stream flow. Results of the effects of the direction and the velocity of principal air flow, convection due to a human body, arm movement of a human being and the type of source on the concentration profiles are presented. Three important results were obtained. Firstly, for a given low and moderate impulse low impulse contaminant source in the near field of a worker, his/her orientation relative to the principal air flow direction is the most important factor in reducing occupational exposure, with an air velocity of about 0.3 m s(-1). Secondly, the effect of convection resulting from body heat on air flow was lower than expected. Thirdly, arm movements influence contaminant dispersion, and should be included when models assessing exposure are developed. The present data can also be used to validate existing computational fluid dynamic (CFD) models.  (+info)

Monitoring response to convection-enhanced taxol delivery in brain tumor patients using diffusion-weighted magnetic resonance imaging. (8/141)

Convection-enhanced drug delivery (CEDD) is a novel approach to enhance the delivery of drugs directly into brain tumors. We have used diffusion-weighted MRI (DWMRI) to monitor the effects of intratumoral CEDD in three brain tumor patients treated with Taxol. Clear changes in the images and the water diffusion parameters were observed shortly after the initiation of treatment. Initially, a bright area corresponding to decreased diffusion appeared, followed by the appearance of a dark area of increased diffusion within the bright area. The time to appearance of the dark area varied among the patients, suggesting different response rates. In this work, we have demonstrated the feasibility of using DWMRI as a noninvasive tool to achieve unique early tissue characterization not attainable by other conventional imaging methods.  (+info)

The evaporation rate and internal convective flows of a sessile droplet with a pinned contact line were formulated and investigated numerically. We developed and analyzed a unified numerical model that includes the effects of temperature, droplet volume, and contact angle on evaporation rate and internal flows. The temperature gradient on the air/liquid interface causes an internal flow due to Marangoni stress, which provides good convective mixing within the droplet, depending upon Marangoni number. As the droplet volume decreases, the thermal gradient becomes smaller and the Marangoni flow becomes negligible. Simultaneously, as the droplet height decreases, evaporation-induced flow creates a large jet-like flow radially toward the contact line. For a droplet containing suspended particles, this jet-like convective flow carries particles toward the contact line and deposits them on the surface, forming the so-called coffee ring stain. In addition, we reported a simple polynomial correlation ...
TY - JOUR. T1 - Finite element computational procedure for convective flow of nanofluids in an annulus. AU - Uddin, M. J.. AU - Rahman, M. M.. PY - 2018/6. Y1 - 2018/6. N2 - In the present study, the detailed procedures of Galerkin weighted residual technique of finite element method (FEM) for solving two-dimensional incompressible natural convective flow of nanofluids using nonhomogeneous dynamic model are discussed for the first time. The physical domain is discretized by using unstructured triangular elements. The governing partial differential equations of nanofluids are made dimensionless using the suitable transformation of variables for weak formulations. The method of weighted residuals is used for obtaining the approximate solutions. This approach typically leads to a sparse and indefinite matrix that is difficult to solve efficiently. The formation of an indefinite matrix is avoided in the present work by introducing an artificial compressibility term in the continuity equation. ...
Convection-enhanced delivery permits the direct homogeneous delivery of small- and large-molecular-weight putative therapeutics to the nervous system in a manner that bypasses the blood-nervous system barrier. The development of co-infused surrogate imaging tracers (for computed tomography and MRI) allows for the real-time, noninvasive monitoring of infusate distribution during convective delivery. Real-time image monitoring of convective distribution of therapeutic agents insures that targeted structures/nervous system regions are adequately perfused, enhances safety, informs efficacy (or lack thereof) of putative agents, and provides critical information regarding the properties of convection-enhanced delivery in normal and various pathologic tissue states ...
Define Convection, Rotation and Planetary Transits. Convection, Rotation and Planetary Transits synonyms, Convection, Rotation and Planetary Transits pronunciation, Convection, Rotation and Planetary Transits translation, English dictionary definition of Convection, Rotation and Planetary Transits. Jean Baptiste Camille 1796-1875. French artist of the Barbizon school whose landscape paintings influenced the impressionists. n Jean Baptiste Camille ....
SADANA BROTHERS - is one of the best manufacturer,supplier & exporter of Gas Convection Apparatus (Ventilation Apparatus, Convection Box) from New Delhi. We provide best quality of Gas Convection Apparatus (Ventilation Apparatus, Convection Box) all over India
This paper describes a novel technique that allows separation and quantification of different sources of convection in the high‐latitude ionosphere. To represent the ionospheric convection electric field, we use the Spherical Elementary Convection Systems representation. We demonstrate how this technique can separate and quantify the contributions from different magnetospheric source regions to the overall ionospheric convection pattern. The technique is in particular useful for distinguishing the contributions of high‐latitude reconnection associated with lobe cells from the low‐latitude reconnection associated with Dungey two‐cell circulation. The results from the current paper are utilized in a companion paper (Reistad et al., 2019, to quantify how the dipole tilt angle influences lobe convection cells. We also describe a relation bridging other representations of the ionospheric convection electric field or potential to the Spherical Elementary ...
Porewater flowlines in the bed of a small Michigan USA river were shown to be altered by Chara hummocks, sea lamprey nests, and beaver dams. Altered flow lines followed expected in-bed convective and underflow patterns predicted from published models. The greater density and shape of Chara hummocks caused upwellings into the hummocks, possibly being of benefit to the plants through contact with higher levels of dissolved substances contained in the cooler, deeper porewater. Streamwater downwelling into the more permeable sea lamprey nests may provide a continuous supply of well-oxygenated water, enhancing egg survival. Convective flow patterns beneath beaver dams, as well as beneath other bed surface features, may function to temporarily store dissolved streamwater substances, altering downstream transport rates, and may function to bring porewater/streamwater to the surface, affecting distributions of surface dwelling organisms.. ...
Liquid lead bismuth eutectic (LBE) is very corrosive to steels. To mitigate structural corrosion of LBE systems, active oxygen control technique is developed. To enhance the speed of oxygen transport in liquid LBE, natural convection has been proposed. This paper numerically analyzes the oxygen transport in a natural convection induced LBE enclosure. Different temperature boundary conditions are added to the container. Both laminar and turbulent LBE flows which are distinguished by strength of flow measured are analyzed. Three laminar cases: (a) heated from the bottom and cooled from the top of the container; (b) heated from the sidewalls and cooled from the top of the container; (c) one sidewall heated and the opposite wall cooled, and one fully turbulent case with one sidewall heated and the opposite sidewall cooled are chosen. Oxidization in near wall areas and formation of oxide layers on container surfaces are considered. In each case, the characteristic velocity and oxygen diffusion time are
Article Entropy generation for unsteady natural convection and thermal radiation inside a porous enclosure. Entropy generation problem for unsteady natural convection and thermal radiation in a vertical porous enclosure, submitted to a uniform hot wa...
A method and system, together with corresponding apparatus and components, and corresponding kits, for use in performing topical wound therapy by using topical negative pressure (TNP) in combination with one or more hollow fiber catheters. In one embodiment, the method provides hollow fiber catheters for the removal of fluid or fluid components from the wound area by ultrafiltration. In another embodiment the hollow fiber catheters are connected to an infusion pump and used to deliver therapeutic fluids to the wound area. In yet another embodiment, a first set of hollow fiber catheters is connected to a vacuum pump and a second set is connected to an infusion pump to simultaneously remove excess tissue fluid and deliver therapeutic fluid to the wound site.
The suns core temperature is around 20,000,000 °K, yet it is not what determines the characteristic electromagnetic radiation emission from the sun, because most of this intense core radiation is absorbed by a layer of negative hydrogen ions outside the suns core called the convection layer. Heat from the core interior passes through the radiative zone, and then accumulates in this convection zone. Once here, currents circulate so that heat is passed to the photosphere at the surface of the sun and the cooler plasma flows back down to carry more energy to the photosphere. The convection process allows heat to be released from surface with gas, much like boiling water releases heat from the waters surface in steam. In the particle view, photons are essentially bouncing around in the region between the core and the photosphere, losing energy and traveling through the convection zone to the photosphere. These photons are then radiated with gases which are still a very high 5760 °K. Because the ...
TY - JOUR. T1 - The effect of temperature-dependent solubility on the onset of thermosolutal convection in a horizontal porous layer. AU - Pritchard, David. AU - Richardson, Chris N.. PY - 2007/1/31. Y1 - 2007/1/31. N2 - We consider the onset of thermosolutal (double-diffusive) convection of a binary fluid in a horizontal porous layer subject to fixed temperatures and chemical equilibrium on the bounding surfaces, in the case when the solubility of the dissolved component depends on temperature. We use a linear stability analysis to investigate how the dissolution or precipitation of this component affects the onset of convection and the selection of an unstable wavenumber; we extend this analysis using a Galerkin method to predict the structure of the initial bifurcation and compare our analytical results with numerical integration of the full nonlinear equations. We find that the reactive term may be stabilizing or destabilizing, with subtle effects particularly when the thermal gradient is ...
An area of convection has persisted near 12.9S 161.1E, approximately 640 nautical miles north-northwest of Noumea, New Caledonia.. The main image here shows the area of convection 36 hours ago, when it was located farther east. The image of the globe shows the systems current location.. Animated METSAT imagery depicts a developing low-level circulation center (LLCC) with flaring deep convection located primarily over the western periphery of the disturbance.. An ASCAT pass shows 10 to 15 knot winds near the center of the tight, but elongated, LLCC.. The system is located in a region of strong, vertical wind which is limiting development at this time.. ...
Conduction Convection Radiation Worksheet. 20 Conduction Convection Radiation Worksheet. Worksheets Convection Conduction Radiation Worksheet
This item is also known as a Convection Box or a Ventilation Apparatus. Use it for demonstrating the phenomenon of convection in air and the principle of room ventilation. It consists of an enameled metal box 4″ (100 mm) W x 8″ (200 mm) L x 4″ (100 mm) H, having a sliding glass door and 2 glass chimneys. When the included tea light candle is placed under 1 chimney and a smoldering tape or parchment paper is placed underneath the other chimney, the flow pattern of smoke dramatically illustrates the formation of convection currents. Tape or parchment paper are not supplied ...
An analysis is made of natural convection mass transfer in a ternary gas mixture adjacent to a vertical plate. The main feature of the analysis is the proper mathematical description of the buoyancy force and of the boundary conditions. With regard to the latter, account is taken of the selective impermeability of the plate to certain components of the mixture. The governing boundary layer equations are shown to admit a similarity solution, and a numerical scheme for solving the similarity equations and boundary conditions is outlined. The general formulation is specialized to the case of sublimation from a solid, vertically oriented naphthalene plate situated in a humid air environment. Solutions were obtained for temperature levels corresponding to those encountered in practice and for relative humidities of water vapor between zero and one. It was found that the mass transfer results were unaffected by the presence of humidity, and this finding gives license to the utilization of the ...
Steady natural convection heat transfer has been studied in porous wall, solar collector systems. The boundary conditions were: two isothermal walls at different temperatures, two horizontal bounding adiabatic walls, and either uniform or nonuniform heat generating porous layer without vents. The aspect ratio A was from 0.5 to 1.4. The Rayleigh number varied from 103 to 108 . The Darcy number was from 10−8 to 10−2 but the detailed studies were carried out only for 10−4 , an optimum value. The results are presented in terms of thermal parameters (θ, θmax , Nu) as a function of Ra and other nondimensional parameters (A=H/L, B=1/L, F=d/L, kr ). The isotherms and streamlines within the system are also produced. The overall results indicate that geometrical parameters are the most important parameters affecting the system performance.. ...
Provides a single-source resource all cylinder heat transfer correlations Presents an exhaustive treatment of natural convection from cylinders including
Introducing Esco Isotherm- world class laboratory incubators for thermal appliations that prefers natural convection design to minimize disturbance to the items being culture such as bacteria culture and Coliform determination among many others.
The composition field in front of a growing lamellar eutectic was determined numerically, both with and without a lateral convective flow. By minimization of the interfacial undercooling it was found...
Convection, process by which heat is transferred by movement of a heated fluid such as air or water. Natural convection results from the tendency of most fluids to expand when heated-i.e., to become less dense and to rise as a result of the increased buoyancy. Circulation caused by this effect
Convective systems dominate the vertical transport of aerosols and trace gases. The most recent in situ aerosol measurements presented here show that the concentrations of primary aerosols including sea salt and black carbon drop by factors of 10 to 10,000 from the surface to the upper troposphere. In this study we show that the default convective transport scheme in the National Science Foundation/Department of Energy Community Earth System Model results in a high bias of 10-1,000 times the measured aerosol mass for black carbon and sea salt in the middle and upper troposphere. A modified transport scheme, which considers aerosol activation from entrained air above the cloud base and aerosol‐cloud interaction associated with convection, dramatically improves model agreement with in situ measurements suggesting that deep convection can efficiently remove primary aerosols. We suggest that models that fail to consider secondary activation may overestimate black carbons radiative forcing by a ...
A framework is introduced to investigate the indirect effect of aerosol loading on tropical deep convection using three-dimensional limited-domain idealized cloud-system-resolving model simulations coupled with large-scale dynamics over fixed sea surface temperature. The large-scale circulation is parameterized using the spectral weak temperature gradient (WTG) approximation that utilizes the dominant balance between adiabatic cooling and diabatic heating in the tropics. The aerosol loading effect is examined by varying the number of cloud condensation nuclei (CCN) available to form cloud droplets in the two-moment bulk microphysics scheme over a wide range of environments from 30 to 5000 cm(-3). The radiative heating is held at a constant prescribed rate in order to isolate the microphysical effects. Analyses are performed over the period after equilibrium is achieved between convection and the large-scale environment. Mean precipitation is found to decrease modestly and monotonically when the ...
A coupled mechanism for molecular aggregation in a thin water solution film by laser-tweezers is suggested based on (i) simulation of light intensity distribution and (ii) order of magnitude analysis of heat and mass transport induced by Marangoni convection. The analysis suggests that the laser induced temperature distribution develops within 1 ms and Marangoni convection flow commences within 0.01-1 s, which increases by 1-2 orders of magnitude the mass transfer of dissolved molecules into the laser focus where they are trapped and aggregate by attractive van der Waals forces. This mechanism, considered for the particular case of polymer assembly, suggests that it can also be successfully applied for assembling other types of clusters and molecular aggregates from solutions.. ©2008 Optical Society of America. Full Article , PDF Article ...
Analytical Solution Of The Diffusion - Convection Equation Over A Finite Domain. Analytical Solution Of The Diffusion - Convection Equation Over A Finite Domain.. ...
Bakery, Convection Systems and Equipment from the EngNet Engineering Directory and search engine. Find suppliers, manufacturers and distributors for Bakery, Convection Systems and Equipment including Catering and Hostelry Equipment, Steam Cooking Systems, Flour Transport Systems, Stainless Steel Dairy Equipment.
Fig. 1 A sampling of the phenomena discussed at the workshop demonstrates the broad range of spatial-temporal scales involved and the cross-scale interactions. The spatial scale ranges from ,1 to ,100,000 kilometers and the temporal scale covers from , 1 hour to multi-years. (Hagos et al., 2019). From 7-9 May 2019, 90 observational and modeling experts met in Boulder CO, USA to review and document progress, identify outstanding issues, and propose approaches for future integrated process studies in atmospheric convection and air-sea interactions over the tropical oceans, over a broad range of spatio-temporal scales. The workshop on Atmospheric Convection and Air-Sea Interactions over the Tropical Oceans was co-organised and co-sponsored by the U.S. and the International CLIVAR programs.. The workshop identified key areas where progress has been made over the last 30 years, including the understanding of key dynamical processes underlying different flavors of El Nino Southern Oscillation ...
We conducted a model study of ground magnetic signatures of traveling convection vortices (TCVs) that included both the ionospheric conductivity enhancement associated with the TCVs and the ground induction effect. We found that the localized conductivity enhancement can cause a significant distortion of the TCV current system and lead to a distortion of the ground magnetic disturbance patterns. The patterns of all three magnetic components are asymmetric, mainly in the E-W direction, and the patterns of the Z component show the strongest asymmetry (20-30%). We also found that the effect of induction currents on ground magnetic signatures of the TCVs is insignificant (less than 5%). The results show that because of the presence of localized conductivity enhancements the polarity and speed of the TCVs can significantly influence the distortion features of ground magnetic patterns. The upward and downward current filaments of a TCV with a clockwise leading convection cell can wrap with each other,
The evolution of a star through the helium flash depends upon uncertain aspects of convection theory. Observations place some constraints on the theory of convection in stellar cores.
Binding of targetted biomolecules, pathogens or analytes on a reactive surface is commonly used for biodiagnostic systems. However the process is slow and inefficient if one relies only on molecular diffusion to transfer the analytes to the immobilized ligand. A micropump based on a Marangoni convection in a droplet geometry has been designed in order to enhance the kinetics of binding. The droplet is suspended to a heated rod and cooled at its bottom, resulting in a gradient of temperature on the liquid-air interface that drives a Marangoni convection inside the droplet. This type of convection has been verified by an experimental set up. We have then developped a numerical model for the calculation of the kinetics of binding: first, a calculation of the Maragoni flow is performed assuming a steady state convection, second, we solve a coupled system for the the concentration of analytes inside the droplet and the adsorption at the wall. The model shows the efficiency of the convection on the kinectics
Experimental and Numerical Analyses of Natural Convection flow in a partially heated Vertical Annulus, Numerical Heat Transfer- Part A, Taylor & Francis, 2017, ISSN: 0891-6152 , Vol. 30, No.1, pp. 25-45.. Experimental Studies on Natural Convection of Water in a Closed Loop Vertical Annulus, Experimental Heat Transfer, Taylor & Francis, 2017, ISSN: 0891-6152 , Vol. 30, No.1 pp. 25-45.. Experimental Study of Boiling Incipience in a Closed Loop Vertical Annular Thermo-siphon, Applied Thermal Engineering, Elsevier Ltd. 2010 , Vol. 30, Issues 11-12 pp.1333-1340.. Heat Transfer Studies during Natural Convection Boiling in an Internally Heated Annulus, Int. J. Heat and Mass Transfer, Elsevier Science Ltd. Pergamon, 2003,Vol. 46, No.6, pp.1085-1095.. Economic Analysis of Two Stage Dual-Fluid Absorption Cycle for Optimizing Generator Temperatures. Energy Convers. & Mmgt. Elsevier Science Ltd. 2001,Vol. 42, pp.407-437.. Performance and Economic study of the combined Absorption/ Compression Heat Pump, ...
Everyone knows that hot fluid rises and cold fluid sinks. These buoyancy driven flows, known as thermal convection, are physical phenomena of great importance for engineering applications and throughout the geophysical and astrophysical sciences. Heat transfer by natural convection is a basic consideration for insulation, ventilation, and climate control in buildings, in automotive engineering and for the thermal management of electronic devices and systems. Thermal convection occurs naturally in the earths atmosphere and oceans and plays a fundamental role in the global heat transfer processes determining the weather and controlling the climate. On geological time scales, convection in the earths mantle is the driving force behind continental drift. On the largest scales, convective heat transport in stars is a primary factor in the balance between ongoing thermonuclear explosions in the core and gravitational attraction that determines their structure.. Despite its ubiquity in everyday life, ...
Fluid Convection, Generation and Reinfusion in Haemodiafiltration. By Emily J. See, Carmel M. Hawley, John WM. Agar and David W. Johnson. Despite widespread use in clinical practice for over 30 years, many questions remain unanswered regarding fluid convection and reinfusion strategies in haemodiafiltration (HDF). Randomised controlled trials have failed to consistently demonstrate improved survival with convective therapies, but a dose-dependent improvement in outcome has been suggested. The minimum and ideal volumes of convection are undefined. Online generation of ultrapure dialysis fluid has allowed unprecedented convection volumes; however, delivery of fluid directly into the blood circuit requires strict monitoring. The replacement fluid may be reinfused at multiple points in the circuit. Post-dilution HDF is highly efficient in terms of solute clearance but is limited by haemoconcentration. Pre-dilution HDF prolongs filter life but requires significant convection volumes to achieve ...
Thirty-one patients with a mean age of 7.6 years (range 3.2-18 years) underwent 39 catheter insertions for CED between 2012 and 2017. Thirty catheter insertions had tractography data available for analysis. The mean trajectory length was 105.5 mm (range 92.7-121.6 mm). The mean number of intersections of CST by catheter was 2.2 (range 0-3) and the mean intersecting length was 18.9 mm (range 0-44.2 mm). The first 9 infusions in the highest dose level (range 3.84-4.54 ml infusate) were analyzed for Vd overlap with CST. In this group, the mean age was 7.6 years (range 5.8-10.3 years), the mean trajectory length was 109.5 mm (range 102.6-122.3 mm), and the mean overlap between Vd and CST was 5.5 cm3. For catheter placement-related adverse events, 1 patient (3%) had worsening of a contralateral facial nerve palsy following the procedure with two CST intersections, an intersecting distance of 31.7 mm, and an overlap between Vd and CST of 3.64 cm3. For infusion-related adverse events, transient ...
Here we review the improvements that have been made to CED devices over recent years and current state of the art for chronic infusion systems.
A Phase II, multi-center, open-label, single-arm study in up to 42 subjects with first recurrence or progression of GBM at up to 12 sites in Australia, Europe, Israel, and the United States. Subjects will receive intratumoral infusion of PRX321 administered via convection-enhanced delivery (CED) at a concentration of 1.5 μg/mL and a total volume of 60 mL over 2 to 7 days.. Primary Objective:. To evaluate the efficacy (expressed as overall survival at 6 months [OS-6]) of intratumoral infusion of PRX321 in subjects with first recurrence or progression of glioblastoma multiforme (GBM).. Secondary Objectives:. To assess the safety of intratumoral infusion with PRX321 in subjects with recurrent or progressive GBM.. To evaluate objective response rate (ORR), duration of response (DR), overall survival (OS), and progression-free survival (PFS).. Tertiary Objective:. To evaluate the relationship of observed infusate distribution with clinical and radiological responses. ...
TY - JOUR. T1 - Effect of Thermal Modulation on the Onset of Convection in Walters B Viscoelastic Fluid-Saturated Porous Medium. AU - Shivakumara, I. S.. AU - Lee, Jinho. AU - Malashetty, M. S.. AU - Sureshkumar, S.. N1 - Funding Information: Acknowledgment One of the authors (ISS) wishes to thank the Brain Korea 21 (BK21) Program of the School of Mechanical Engineering, Yonsei University, Seoul, Korea, for inviting him as a visiting Professor and also the Bangalore University for sanctioning sabbatical leave. The work of MSM is supported by UGC under DRS program. The author SSK wishes to thank the President and Principal of his college for their encouragement and support.. PY - 2011/3. Y1 - 2011/3. N2 - The linear stability of Walters B viscoelastic fluid-saturated horizontal porous layer is examined theoretically when the walls of the porous layer are subjected to time-periodic temperature modulation. Three types of boundary temperature modulations are considered namely, symmetric, asymmetric, ...
Thermocapillary-driven convection in a thin liquid layer of up to 2 mm in depth was experimentally investigated under the normal gravity condition. Silicone oil of 2, 5, 10 and 20 cSt was employed as the test fluid. In the present study, temperature gradient was applied to the liquid layer with an inclination to the free surface; i.e., perpendicular- and parallel-temperature gradients were imposed to the free surface simultaneously. The flow fields obtained in the terrestrial experiments were categorized into five patterns; Marangoni-Benard convection, Flowing Bénard cells, Streak convection and Horizontal circulation with increasing horizontal Marangoni effect, and Stagnation. The occurrence conditions of these flow patterns were obtained in terms of the horizontal- and vertical-Marangoni numbers ...
Conduction, convection, and radiation are all forms of heat transfer, but they rely on different physical interactions to transfer heat. Conduction occurs when heated solid matter transfers heat....
PAN Czytelnia Czasopism, Numerical simulation of forced convection of nanofluid around a circular cylinder - Archives of Thermodynamics
1 1 sin dx using Gauss Quadrature Method. x x 3 b) Explain and draw flow chart for Simpsons 8 y = f(x). 8 th rule to find area under the curve 8 [3663] 107 4 *3663107* 6 11. a) Explain the use of computers in construction project management. b) Write an algorithm to find critical path in a CPM network. 6[price]Applied RheologyPublications[hdpe]Heat Transfer of Third Grade Fluid Flow in a Pipe Under An Externally Applied Magnetic Field with Convection on Wall Appl. Rheol. 28:5 (2018) 56023 (11 pages) In this research, a fully developed steady flow of a third Grade fluid in a pipe under an externally applied maGnetic field with convection on [price][3663] 101 PDF Free Download ZOMBIEDOC.COM[hdpe]1 1 sin dx using Gauss Quadrature Method. x x 3 b) Explain and draw flow chart for Simpsons 8 y = f(x). 8 th rule to find area under the curve 8 [3663] 107 4 *3663107* 6 11. a) Explain the use of computers in construction project management. b) Write an algorithm to find critical path in a CPM network. ...
A fully coupled meteorology‐chemistry‐aerosol mesoscale model (WRF‐Chem) is used to simulate a multiday biomass burning event in the dry season of South America. The effects of biomass burning aerosols on clouds and precipitation are described at both 36 km and 4 km horizontal resolutions. The dominant effect of the aerosols is to reduce the diurnal amplitude of convection by decreasing clouds and precipitation in the afternoon but increasing them at night, with the afternoon decrease greater than the nighttime increase on the daily mean. On average, the decrease of surface precipitation is about 5% (3%) and the amplitude of diurnal cycle is reduced by about 11% (5%) in the 36 km (4 km) simulations. Such a modulation of clouds and precipitation is primarily contributed by the aerosol radiative effect, i.e., their ability to scatter and absorb solar radiation. The aerosol microphysical effect as cloud condensation nuclei tends to act oppositely to the aerosol radiative effect but with a ...
V. P. Trubitsyn and A. M. Bobrov Abstract Thermomechanical interaction between the mantle and continents strongly affects mantle convection patterns. We present a numerical study of this interaction. Numerical models of mantle convection with free-floating rigid continents must include boundary conditions at mantle-continent interfaces. We state these conditions using solutions at successive time steps $\Delta t$. First, with fixed positions of continents, thermal convection is calculated for the whole region excluding the continents; then the instantaneous velocity $V$ of their displacement can be obtained. At the next time step mantle convection is calculated with the new positions of continents now shifted by the distance $V\Delta t$. No-slip conditions at the mantle-continent interface cannot be used, because $V$ equals zero in that case. We suggest boundary conditions at mantle-continent interfaces where velocities of the continents are accepted to be equal to the mean velocities of the ...
Despite the improvements in the parameterizations of physical processes and higher grid spacings of numerical weather prediction (NWP) models over the past decades, quantitative precipitation forecasting still remains a challenge for state-of-the-art numerical models. In particular, the forecast of deep moist convection in situations with weak synoptic forcing over both flat and orographically structured terrain is still inadequate for many applications. With prevailing weak synoptic-scale forcing, land-atmosphere interactions are assumed to be decisive for cloud formation and subsequent convective precipitation. Surface heterogeneities ranging from large scales (100 km) to kilometric scales can cause atmospheric circulations which themselves modify the boundary layer structure and cloud formation. For example, soil moisture influences heat and moisture fluxes into the planetary boundary layer and uncertainties in the initial state can introduce large forecast errors. Furthermore, the feedback ...
TY - GEN. T1 - Effect of Enhanced Cerebrospinal Fluid Flow on Drug Penetration in Convection Enhanced Delivery. AU - Zhan, Wenbo. AU - Tan, Zhengchu. AU - Bernardini, Andrea AU - Dini, Daniele. AU - Baena, Ferdinando Rodriguez y. PY - 2019/9/5. Y1 - 2019/9/5. M3 - Conference contribution. BT - BioMedEng Conference. PB - BioMedEng. ER - ...
Convection motions within the Sun transport heat from its interior to its surface. The hot regions are seen as granular (∼1000 kilometers across) and supergranular (∼30,000 kilometers across) cells in the Sun. Using data from the Helioseismic Magnetic Imager on the Solar Dynamics Observatory, Hathaway et al. (p. 1217) found evidence for even larger cells that have long been predicted by theory but not unambiguously detected. The flows associated with these giant cells transport angular momentum toward the equator and are important for maintaining the Suns equatorial rotation.. Video follows: GO WITH THE FLOW Long-lasting plasma flows appear in red and blue in this animation, which portrays data from four solar rotations. Some flows persist for several months; these patterns are especially visible near the suns north pole. Scientists think these flows keep the suns equator rotating faster than its poles.. ...
The proposition that a high rate of evapotranspiration from forested regions is a prime mover of major air mass convection has remained contentious. Meesters et al. (2009) rejected the BPT on the grounds that the ascending air motions induced by the evaporative/condensation force would rapidly restore hydrostatic equilibrium and thereby become extinguished. In reply Makarieva et al. (2009) pointed out that condensation removed water vapour molecules from the gas phase and reduced the weight of the air column. That removal must disturb hydrostatic equilibrium and make air circulate under the action of the evaporation/condensation force (Makarieva, 2009). The mass of an air column is equal to the number of air molecules in the column multiplied by their molecular masses. When the number of air molecules in the column is preserved, its weight remains unchanged and independent of density. Hence, heating of the air column does not change its weight. In contrast, condensation changes the number of gas ...
Charney and Eliassen (1964) argued in essence that the depth of the free tropospheric secondary circulation associated with cross-isobaric frictional flow is comparable to the depth of the troposphere. As noted in section 1, the steady-state approximation would be valid if this were true, and the vertical motion at the top of the boundary layer could be said to be caused by the action of surface friction. However, as we have shown, typical values of atmospheric stratification result in a far shallower secondary circulation in response to surface friction. Under these circumstances, the time tendency of the wind along the isobars cannot be neglected for a flow of any reasonable horizontal scale (say , 1000 km) in the tropics. For horizontal scales of order 100 km or less, the vertical scale of the secondary circulation is typically much smaller than the thickness of the layer over which surface friction is deposited, especially when there is widespread shallow, moist convection such as occurs in ...
Fingerprint Dive into the research topics of Taylor dispersion in the presence of time-periodic convection phenomena. Part I. Local-space periodicity. Together they form a unique fingerprint. ...
Adiabatic cooling occurs when air rises and expands.[14] The air can rise due to convection, large-scale atmospheric motions, ... Most precipitation occurs within the tropics[4] and is caused by convection. The movement of the monsoon trough, or ... Robert A. Houze Jr (1997). "Stratiform Precipitation in Regions of Convection: A Meteorological Paradox?". Bulletin of the ... IR works best in cases of deep, vigorous convection-such as the tropics-and becomes progressively less useful in areas where ...
... is also sometimes known as "Bénard-Rayleigh convection", "Bénard convection", or "Rayleigh ... Rayleigh-Bénard convection is a type of natural convection, occurring in a plane horizontal layer of fluid heated from below, ... Rayleigh-Bénard convection is one of the most commonly studied convection phenomena because of its analytical and experimental ... a b Pearson, J.R.A (1958). On convection cells induced by surface tension, Journal of Fluid Mechanics. ...
Adiabatic cooling occurs when air rises and expands.[7] The air can rise due to convection, large-scale atmospheric motions, or ... Robert Houze (October 1997). "Stratiform Precipitation in Regions of Convection: A Meteorological Paradox?". Bulletin of the ... with thunderstorms possible if the atmosphere along the trowal is unstable enough for convection.[75] Banding within the comma ... Graupel and hail indicate convection.[43] In mid-latitudes, convective precipitation is intermittent and often associated with ...
Glatzmaier, Gary A. (2013). Introduction to Modeling Convection in Planets and Stars: Magnetic Field, Density Stratification, ... How mantle convection directly and indirectly relates to plate motion is a matter of ongoing study and discussion in ... Lately, the convection theory has been much debated, as modern techniques based on 3D seismic tomography still fail to ... Schubert, Gerald; Turcotte, Donald L.; Olson, Peter (2001). Mantle Convection in the Earth and Planets. Cambridge: Cambridge ...
is proportional to the rate of convection, y. {\displaystyle y}. to the horizontal temperature variation, and z. {\displaystyle ... This point corresponds to no convection. All orbits converge to the origin, which is a global attractor, when ρ. ,. 1. {\ ... Derivation of the Lorenz equations as a model of atmospheric convection[edit]. The Lorenz equations are derived from the ... Saltzman, Barry (1962). "Finite Amplitude Free Convection as an Initial Value Problem-I". Journal of the Atmospheric Sciences. ...
Convection. Radiation. CD 3-way split w/ The Wind-Up Bird and 1 Mile North (Music Fellowship) Travels In Constants (Vol. 18): ...
"Convection". Retrieved 2019-03-02. "NSF Award Search: Award#1019151 - Workshop Support for "Particulate Matter: ...
When the convection is strong and linear or curved, the MCS is called a squall line, with the feature placed at the leading ... In the warm season, lee troughs, breezes, outflow boundaries and occlusions can lead to convection if enough moisture is ... "Convection". Glossary of Meteorology. American Meteorological Society. Retrieved 2006-10-22. "Orographic Lifting". Glossary of ...
It has a strong cross-breeze from the courtyard, at least partly driven by convection;[4]:Ch. 6[5] it thus uses the courtyard ...
In this case, overturning or convection generally ensues. The Brunt-Väisälä frequency relates to internal gravity waves: it is ... Emmanuel, K.A. (1994). Atmospheric Convection. Oxford University Press. doi:10.1002/joc.3370150709. ISBN 0195066308. ... is a measure of the stability of a fluid to vertical displacements such as those caused by convection. More precisely it is the ...
Through 2012, X-Acto sold ceramic and convection space heaters and fans under the Boston brand name. Knife Scalpel Arts and ... "Ceramic Heaters , Heater with Fan , Convection Heater , X-ACTO". 24 May 2012. Archived from the original on 24 March 2012. ...
These students studied thermal convection in various regimes, including electroconvection, surface tension-driven convection, ... They went on to attempt 'to define and to measure in a horizontal liquid layer heated from below, the convection currents that ... He also measured the aspect ratio of the cells and discovered that there was a critical temperature below which no convection ... He and his student Avsec published a major review article of their work on thermal convection in 1938. Finally, on 29 March ...
... developed theory of convection in the Earth's mantle, applications of fractals and chaos to Earth processes; William Bowie ... mantle convection; sedimentary basin formation; Crafoord Prize Harry Mayne (American, 1913-1990) - exploration geophysicist, ...
Bejan, A. (1984). Convection Heat Transfer. John Wiley & Sons.. *^ Cunningham, R. E.; Williams, R. J. J. (1980). Diffusion in ... the Brinkman equation is connected to a set of reaction-diffusion-convection equations. ...
In the proposed model, the Brinkman equation is connected to a set of reaction-diffusion-convection equations. Darcy's law is ... "The physics of a stove-top espresso machine". American Journal of Physics (2008) Bejan, A. (1984). Convection Heat Transfer. ...
Osmosis, diffusion, convection. Am. J. Physiol. 235:R3-R17, 1978. Soodak, H. and A.S. Iberall. Forum on osmosis. IV. More on ...
This is also known as having CAPE or convective available potential energy); see atmospheric convection.) A convective boundary ...
ISBN 0-262-20019-8. CS1 maint: discouraged parameter (link) Bejan, A. (2004). Convection Heat Transfer. John Wiley & sons. ISBN ...
Another form of convection is forced convection. In this case the fluid is forced to flow by use of a pump, fan or other ... Another form of convection is forced convection. In this case the fluid is forced to flow by using a pump, fan or other ... It is a measure which determines the relative strength of conduction and convection. R a = G r ⋅ P r = g Δ ρ L 3 μ α = g β Δ T ... Heat convection occurs when bulk flow of a fluid (gas or liquid) carries heat along with the flow of matter in the fluid. The ...
Small-scale sublithospheric convection; Oceanic intraplate extension; Slab tearing and break-off; Shallow mantle convection; ... Tan, K. K.; Thorpe, R. B. (1999). "The onset of convection driven by buoyancy caused by various modes of transient heat ... doi:10.1016/S0009-2509(98)00248-6. Tan, K.K. & Thorpe, R. B. (1999). "The onset of convection driven by buoyancy caused by ... A mantle plume is a proposed mechanism of convection within the Earth's mantle. Because the plume head partially melts on ...
From 1992 to 1996 he published four more books, Convection in Porous Media, Heat Transfer, Thermal Design and Optimization and ... In 1984 he published Convection Heat Transfer'. In an era when researchers did heat transfer calculations using numerical ... Bejan, Adrian; Khair, Khairy R. (1985). "Heat and mass transfer by natural convection in a porous medium". International ... ISBN 978-0-471-89612-8., updated in 1995, 2004, and 2013: Bejan, Adrian (2013). Convection Heat Transfer (4th ed.). Wiley. ISBN ...
Fowler, A. C. (1985). "Fast Thermoviscous Convection". Studies in Applied Mathematics. 72 (3): 189-219. doi:10.1002/ ... "Three-Dimensional Simulations of Mantle Convection in Io". Icarus. 149 (1): 79-93. Bibcode:2001Icar..149...79T. doi:10.1006/ ...
Convection subsequently increased. By September 3 it was definitely a tropical cyclone as an eye slowly formed. It then became ...
... whole-mantle convection proponents and layered-mantle convection proponents. Layered-mantle convection proponents hold that the ... Whole-mantle (simple) convection proponents hold that the mantle's observed density differences (which are inferred to be ... Mantle dynamics is likely a mix of the two end-member hypotheses, resulting in a partially layered mantle convection system. ... Albarede, F.; Van Der Hilst, R. D. (2002). "Zoned mantle convection". Philosophical Transactions of the Royal Society A: ...
Bejan, Adrian (2013). "Frontmatter". Convection Heat Transfer. John Wiley & Sons, Inc. pp. i-xxxiii. doi:10.1002/9781118671627. ...
Precipitation and Convection". Intergovernmental Panel on Climate Change. Archived from the original on 2007-11-22. Retrieved ... Precipitation and Convection". Intergovernmental Panel on Climate Change. Archived from the original on 2007-12-09. Retrieved ... Increases in temperature are expected to produce more intense convection over land and a higher frequency of the most severe ... Del Genio, Tony (2007). "Will moist convection be stronger in a warmer climate?". Geophysical Research Letters. 34 (16): L16703 ...
p. 3.2 Mantle convection. Retrieved 23 November 2013. Dumé, Belle (27 July 2005). "Geoneutrinos make their debut; Radiogenic ...
Cannon, D. J.; Troy, C. D.; Liao, Q.; Bootsma, H. A. (2019-06-28). "Ice‐Free Radiative Convection Drives Spring Mixing in a ... Kelley, Dan E. (1997). "Convection in ice-covered lakes: effects on algal suspension". Journal of Plankton Research. 19 (12): ... Austin, Jay A. (2019-04-22). "Observations of radiatively driven convection in a deep lake". Limnology and Oceanography. 64 (5 ... Bouffard, Damien; Wüest, Alfred (2019-01-05). "Convection in Lakes" (PDF). Annual Review of Fluid Mechanics. 51 (1): 189-215. ...
Balmforth, Neil J.; Rust, Alison C. (May 2009). "Weakly nonlinear viscoplastic convection". Journal of Non-Newtonian Fluid ...
ISBN 81-7764-653-2. B. M. Boubnov, G. S. Golitsyn (1995). Convection in Rotating Fluids. Springer. p. 8. ISBN 0-7923-3371-3. ...
Buoyant convection begins at the level of free convection (LFC), above which an air parcel may ascend through the free ... The latent heat release from condensation is the determinate between significant convection and almost no convection at all. ... "Open-ocean deep convection".. *^ National Weather Service Forecast Office in Tucson, Arizona (2008). "What is a monsoon?". ... "Shallow/Deep Convection". National Centers for Environmental Prediction. 15 March 1999.. *^ Helen Jones. " ...
Granular convection has been probed by the use of MRI [8] where convection rolls similar to those in fluids (Bénard cells) can ... Under experimental conditions, granular convection of variously sized particles has been observed forming convection cells ... Granular Convection and Size Separation. The University of Chicago *^ Rosato, A.; Strandburg, K.J.; Prinz, F.; Swendsen, R.H. ( ... If a large particle is involved, it will be moved up to the top by convection flow. Once at the top, the large particle will ...
Natural convection results from the tendency of most fluids to expand when heated-i.e., to become less dense and to rise as a ... Convection, process by which heat is transferred by movement of a heated fluid such as air or water. ... atmosphere: Convection. Vertical mixing (convection) occurs in the atmosphere as well as in bodies of water. This process of ... Natural convection results from the tendency of most fluids to expand when heated-i.e., to become less dense and to rise as a ...
Panasonic India offers microwave convection ovens which are designed with dual heating, 20L - 27L capacity, black mirror finish ...
... referred to as free convection, occurs when the environmental lapse rate (the rate of change of an atmospheric variable, such ... In atmosphere: Convection. This process, referred to as free convection, occurs when the environmental lapse rate (the rate of ... to as free convection (or natural convection), occurs when the environmental lapse rate (the rate of change of an atmospheric ... Alternative Titles: convective turbulence, natural convection. Learn about this topic in these articles:. importance in Earth ...
... referred to as a form of convection, e.g. thermo-capilliary convection and Granular convection. Convection occurs on a large ... In thermodynamics "convection" often refers to heat transfer by convection, where the prefixed variant Natural Convection is ... The convection zone of a star is the range of radii in which energy is transported primarily by convection. Granules on the ... A convection cell, also known as a Bénard cell, is a characteristic fluid flow pattern in many convection systems. A rising ...
Convection Oven - • 23L Compact Double Heater Oven • Large-area flat cavity • Double Heater Oven 40°C, 100-220°C • Simultaneous ...
Artisans who make mezcal, a traditional Mexican spirit, have known for centuries that long-lasting bubbles on the surface of the beverage is an indicator that it has been distilled to the right alcohol level. A new study reveals the science behind why that is. In part, it has to do with whats known as the Marangoni effect. Certain chemicals in mezcal cause liquid to convect upwards into the membranes of bubbles, which helps sustain them for a longer period.
Movement, or convection, in this layer is also responsible for all of Earths volcanic and seismic activity. Information about ... A stable atmospheric event thats found here on Earth as well, open cell convection can be compared to the action of boiling ... This in turn is believed to cause the liquid elements to become buoyant, helping to drive convection in the outer core. This ... What were seeing here is thought to be an open cell convection process in Titans upper atmosphere. In open cells, air sinks ...
The size of convection cells is largely determined by the fluids properties. Convection cells can even occur when the heating ... Such movement is called convection, and the moving body of liquid is referred to as a convection cell. This particular type of ... Convection usually requires a gravitational field, but in microgravity experiments, thermal convection has been observed ... Convection cells can form in any fluid, including the Earths atmosphere (where they are called Hadley cells), boiling water, ...
Use a convection oven to speed the turkey cook time per pound. The hot air circulating around the turkey reduces the overall ... Convection Oven Cooking Turkey Time Per Pound By Ruth de Jauregui Updated March 27, 2019 ... Because the convection oven depends on air circulation to speed the cooking process, use a roasting pan with low sides. If you ... A convection oven is a time-saving addition to your kitchen. The primary difference between a conventional oven and a ...
... a single-source resource all cylinder heat transfer correlations Presents an exhaustive treatment of natural convection from ... Natural Convection from Circular Cylinders. Authors. * Sandra Boetcher Series Title. SpringerBriefs in Thermal Engineering and ... This book covers all natural convection heat transfer laws for vertical and inclined cylinders and is an excellent resource for ... Presents an exhaustive treatment of natural convection from cylinders including robust data sets collected from hard-to-find ...
AirFryer Convection Oven is a premium full-s ... 7 Cooking Functions - AirFry, Convection Bake, Convection Broil ... TOA-60A - Introducing a healthier way to fry, and so much more! The Cuisinart® AirFryer Convection Oven is a premium full-size ... Enjoy the crunch without the calories and messy cleanup, with the AirFryer Convection Oven from Cuisinart®! Easy ...
A convection-cooled electronic system includes an electronic device and a stand. The electronic device has air intake openings ... In operation, the heat emitted by the electronic components within the device housing creates airflow by convection. Convection ... A convection-cooled electronic system includes an electronic device and a stand. The electronic device has air intake openings ... Embodiments of the invention relate to a system and method in which an electronic device is cooled by air convection through a ...
Convection cell definition, a distinct volume of circulating fluid, in a fluid medium under gravity, that is heated from below ... convection cell. convalesce, convalescence, convalescent, convect, convection, convection cell, convection oven, convection ...
Convection ovens take the term full of hot air to an optimistic level. The convection oven, using hot air to help decrease ... Save money now and later with a rebate on a high-efficiency natural gas convection oven and reduce operating and energy costs. ...
Convection ovens boast the ability to cook food faster, more evenly, and with better browning, while also saving energy ... Best Convection Ovens. Convection ovens boast the ability to cook food faster, more evenly, and with better browning, while ... Convection ovens come in a range of different sizes, and most offer a variety of functions designed for different foods, like ... As the most affordable pick here, this Oster oven is a great choice for those who want to add a convection oven to their ...
Rayleigh-Bénard Convection. A model of thermal convection. Figure 1: Box filled with water. The bottom plate is heated, the top ... Heat transport by turbulent convection.. J. Fluid Mech. 17, 405 (1963). *Busse, F.H.. Fundamentals of Thermal Convection.. ... Convection in Stars I. Basic Boussinesq Convection.. Ann. Rev Astron. Astrophys. 98, 323 (1971) ... Rayleigh-Bénard convection (RBC) is the buoyancy-driven flow of a fluid heated from below and cooled from above. This model of ...
Samsung 28 L Convection Microwave MC288TVTCSQ/TL with Slim fry. Microwave oven with curd making, 150 Indian menus, Tandoor ... MC288TVTCSQ Convection MWO with Slim Fry, 28 L. MC288TVTCSQ/TL MC288TVTCSQ Convection MWO with Slim Fry, 28 L is rated 5.0 out ...
A combination machine like the convection microwave has expanded cooking capabilities, and anyone who ponies up for one of ... if using the convection component. Its just like an oven - same pots and pans, except the cook time is shorter due to the fan ... I own a Panasonic convection micro combo- given to me without the original users instructions. I reheated one of those white ... In a convection and in a conventional oven yes. NOT in a microwave oven. Sure as long as it is not a microwave oven. ...
Nokia sites use cookies to improve and personalize your experience and to display advertisements. The sites may also include cookies from third parties. By using this site, you consent to the use of cookies. Learn more ...
Sato, T., Maeda, K., Nagataki, S. et al. High-entropy ejecta plumes in Cassiopeia A from neutrino-driven convection. Nature 592 ... High-entropy ejecta plumes in Cassiopeia A from neutrino-driven convection. *Toshiki Sato. ORCID: ... I. Neutrino-driven convection, Rayleigh-Taylor instabilities, and the formation and propagation of metal clumps. Astron. ...
... J Neurosci Methods. 2016 Feb 1;259:47-56. doi: 10.1016/j.jneumeth. ... Background: Intraparenchymal convection-enhanced delivery (CED) of therapeutics directly into the brain has long been endorsed ...
Find out what a convection microwave is, how it works, what you can cook in it and how it can benefit you as a second oven in ... Convection oven vs. regular oven. What, exactly, is a convection oven? Learn more to determine if you should stick with ... But did you know investing in convection microwave cooking lets you use your microwave like a second oven? In a convection ... Convection microwave cooking means you can use your microwave to:. *Roast an entire chicken, then bake angel food cake for ...
... leading to the self-aggregation of convection. Clouds fascinate people in many ways and with the right amount of imagination ... where the radiative cooling is balanced by randomly distributed moist convection, called radiative-convective-equilibrium. It ...
Observations from NASAs orbiting Solar Dynamics Observatory enabled scientists to confirm the existence of giant flows of gases and plasma moving heat from the suns core to its surface, ending 45 years of speculation and helping better understand sunspot activity that can disrupt communications on Earth.
Visualize the fluid motion of convection cells. This phenomenon occurs all around us but is usually unseen. For this activity, ... Pie-Pan Convection. Its cool to be dense-just watch these convection cells.. Visualize the fluid motion of convection cells. ... Convection happens in all types of fluids and locations. You can discover it in: * Liquids: Convection cells occur in liquids ... This causes the convection cells to widen and become extremely well defined. This slowing of the convection process allows the ...
Weather for UK, Ireland and the world. Sailing, Marine Weather, Weather maps, radar, satellite, climate, historic weather data, information about meteorology, reports, weather warning.
Convection currents occur due to the density difference between hot and cold fluids. A fluid that is heated from below expands ... How does convection work?. A: Convection works by transferring heat from a hot substance to a cooler one through the motion of ... Convection currents occur due to the density difference between hot and cold fluids. A fluid that is heated from below expands ... Convection is the only one of the three heat transfer methods to involve the movement of matter. The other two methods, ...
A convection oven is an oven that creates a uniform temperature with internal fans. Convection ovens are the best for ensuring ... Im just now learning to use my new convection/microwave oven in our new RV. Can you make toast in the convection oven and if ... I am planning to replace my microwave with a convection oven because of health concerns. Is a convection oven useful in warming ... Does anyone know if you can microwave immediately after using the convection part of the microwave convection oven or do you ...
  • A convection oven is a time-saving addition to your kitchen. (
  • The primary difference between a conventional oven and a convection oven is the addition of one or two fans to circulate the hot air. (
  • When using convection to roast a turkey, the time per pound will vary, depending on the oven temperature. (
  • A careful review of your convection oven manual will reveal if it automatically adjusts the temperature of the oven, or if you should reduce the heat by 25 to 50 degrees Fahrenheit to ensure even cooking. (
  • You can speed up the turkey cook time per pound by setting the convection oven at the 'normal' 325 to 350 degrees Fahrenheit that you would use for a conventional gas or electric oven. (
  • Alternately, you can reduce the convection oven temperature to 300 degrees Fahrenheit and roast the turkey for approximately 20 minutes per pound. (
  • Because the convection oven depends on air circulation to speed the cooking process, use a roasting pan with low sides. (
  • The Cuisinart ® AirFryer Convection Oven is a premium full-size toaster oven with a built-in air fryer. (
  • The convection oven, using hot air to help decrease cook times, has become the workhorse and the most widely used appliance in the commercial foodservice industry. (
  • Save money now and later with a rebate on a high-efficiency natural gas convection oven and reduce operating and energy costs. (
  • Convection ovens boast the ability to cook food faster, more evenly, and with better browning, while also saving energy compared to a traditional oven. (
  • To help you find the best convection oven for your kitchen, we've pulled together four great options. (
  • Using what Breville terms "Element IQ" technology, this Breville convection oven is designed to adjust its heat distribution and power, depending on what you're cooking. (
  • As the most affordable pick here, this Oster oven is a great choice for those who want to add a convection oven to their kitchen without breaking the bank, while still getting impressive features like a removable crumb tray and wide temperature range. (
  • With an impressively large interior that can fit two 16-inch pizzas, this Oster convection oven is the largest option on our list, making it a great choice for those who want to cook large batches or need to serve a crowd. (
  • Boasting the largest capacity on our list and the only option with a French door design, this Oster convection oven is a great option for those in search of a large oven that can cook a ton at one time. (
  • Things cook faster in a convection oven. (
  • A convection microwave can double as another oven or even serve as the main oven in small spaces like RVs. (
  • But did you know investing in convection microwave cooking lets you use your microwave like a second oven? (
  • Convection microwaves do this as well, but also have another function that lets you use your microwave like you might use a small oven. (
  • What is a Convection Oven? (
  • Rather than let hot air circulate randomly, a convection oven carefully creates a uniform temperature with internal fans that evenly circulate hot air. (
  • A convection oven can correct this variation by using a fan that blows pre-heated air throughout the oven and around the food, rather than simply surrounding food with heated air. (
  • A convection oven may also do a better job at sealing in the juices of meat so dishes taste more flavorful and moist. (
  • Cooking with a convection oven requires some adjustments, such as figuring out new cook times and temperatures. (
  • Convection oven primarily concern the transfer of heat via movement of gas or liquid to process food. (
  • just bought an older RV that has a convection oven, microwave. (
  • Do you have to preheat a convection oven? (
  • I just had my convection oven fan motor replaced because the fan stated making a loud noise when it was on. (
  • Am I to believe him or should there be two fans in order for the convection part of oven to work as such? (
  • The perfect oven for curing your Kliar e-coated jewelry pieces, this convection oven features an advanced airflow design with patented baffle and squirrel cage fan that ensure a highly effective distribution of heat. (
  • Gas convection double oven. (
  • F1 code GE profile convection self clean wall oven (95? (
  • Industrial Microwave Convection Oven Material that needs to be dried, slips from the feed bin and feed into the cylinder, which is pushed back by the spiral plate. (
  • Due to the tilting of the Industrial Microwave Convection Oven, the material flows to the back end under the action of gravity and rotation. (
  • Industrial Microwave Convection Oven is broadly divided into: Swing Industrial Microwave Convection Oven, Drum Industrial Microwave Convection Oven, Industrial Dryer. (
  • Industrial Microwave Convection Oven is one of the main equipments in mineral processing equipment. (
  • A convection oven comes equipped with a fan and exhaust system that actually pulls the hot oven air across the food and then vents it back out. (
  • Parson feels that this isn't always a bad thing, and that a convection oven is great for cooking some kinds of foods but not others. (
  • Most convection ovens for the home allow you to choose whether to cook something on the convection setting or a regular oven setting. (
  • In a convection oven, you'll get that crisp, crackling skin while the interior stays moist and tender. (
  • We also know from our own experience that the cooking time in a convection oven is about a third that of a normal oven. (
  • Cooking and reheating dishes is fast and convenient with the Sharp 1000W Large Convection Microwave Oven. (
  • Place rack in the Cuisinart® Exact Heat™ Convection Toaster Oven Broiler in position B. Preheat to 425˚F on Bake or Convection Bake for 10 minutes. (
  • Test your culinary skills, and put your chef instincts to work with this LG convection microwave oven. (
  • Whether you're cooking for one or preparing dinner for your entire family, this LG convection microwave oven makes the process simple and quick so you're not inconvenienced in any way. (
  • This month, I'm giving away a Breville OV800XL Smart Oven 1800-Watt Convection Toaster Oven with Element IQ to one of you. (
  • This Avantco COHANDLE1 handle serves as a direct replacement to the one that came with your Avantco CO-14 countertop convection oven. (
  • Its 4.1 cu. ft. oven capacity provides enough room to cook multiple dishes at once, with Even-Heat True Convection for mouthwatering finishes. (
  • Convection ovens take the term 'full of hot air' to an optimistic level. (
  • Convection ovens come in a range of different sizes, and most offer a variety of functions designed for different foods, like pizzas, toast, baked goods, and more. (
  • Convection ovens are often more expensive than standard, or radiant, ovens, but they cook food faster, at a lower temperature, and often with better results. (
  • Most convection ovens also have a broiler, allowing food to be exposed to high heat when required. (
  • And no to the other Anon-- convection ovens do not produce radioactive energy. (
  • When convection ovens were first introduced to the home market, they were heralded as the ultimate time saver: "Perfect roast chicken in a third of the time! (
  • But Evan Kleiman's guest Russ Parsons cautions us that convection ovens aren't always great for everything. (
  • Parsons says that convection ovens are fantastic for doing any kind of roasting. (
  • In fact, the dry heat of convection ovens is the best modern-day equivalent to traditional spit-roasting over open flames! (
  • Convection ovens are also good for cooking some kinds of pastries, particularly pies and cookies. (
  • What's your opinion on convection ovens? (
  • There is a huge selection of standalone microwave ovens that come in features like stainless steel, inverter ovens and convection ovens. (
  • VWR Gravity Convection Ovens - Model 52201-300 - Each : Four Sizes-1.0, 2.0, 4.0, 6.0 cu. ft. (
  • Commercial convection ovens are ideal for smaller kitchens that do a lot of baking. (
  • Unlike traditional ovens, many convection ovens can sit right on your cabinet and require only a working outlet to work. (
  • Convection ovens let you bake more items at a time, so whether you're making cookies, cupcakes, pies or more, you'll always be ready with more inventory to sell! (
  • Once at the top, the large particle will stay there because the convection currents are too narrow to sweep it down along the wall. (
  • Atmospheric convection currents can be set up by local heating effects such as solar radiation (heating and rising) or contact with cold surface masses (cooling and sinking). (
  • Such convection currents primarily move vertically and account for many atmospheric phenomena, such as clouds and thunderstorms. (
  • These density differences result in rising and/or falling currents, which are the key characteristics of a convection cell. (
  • The food coloring will give your solution some contrast and will allow you to more easily see the convection currents and fluid flow. (
  • Adding food coloring highlights the movement of these convection currents. (
  • How are convection currents related to density? (
  • Convection currents occur due to the density difference between hot and cold fluids. (
  • Where do convection currents flow in the Earth? (
  • Convection currents flow in the asthenosphere, immediately below the rocky outer lithosphere. (
  • Convection currents are one of three types of heat transfer, which involve the movement of energy from a warmer object to a cooler object. (
  • Convection currents start in the Earth's core and mantle. (
  • How do convection currents move tectonic plates? (
  • Convection currents move tectonic plates when there is heat inside the mantle that is rising and falling. (
  • Join Hannah, Nimisha, and special guest Olivia as we create colorful convection currents in our home laboratory! (
  • Aerodynamic measurements taken on the basis of formulae proposed in the literature, to determine the air velocity distribution in convection currents formed on the surface of baths at temperatures well above that of the ambient air, are described in an attempt to obtain data for ventilation design. (
  • When convection currents are illustrated they are often painted as arrows with red and blue color, the red one being the direction of warmer currents and the blue ones being the direction of cooler currents. (
  • Natural convection results from the tendency of most fluids to expand when heated- i.e., to become less dense and to rise as a result of the increased buoyancy. (
  • Heat transfer by natural convection plays a role in the structure of Earth's atmosphere, its oceans, and its [mantle. (
  • Natural convection also plays a role in stellar physics. (
  • In thermodynamics "convection" often refers to heat transfer by convection, where the prefixed variant Natural Convection is used to distinguish the fluid mechanics concept of Convection (covered in this article) from convective heat transfer. (
  • This book covers all natural convection heat transfer laws for vertical and inclined cylinders and is an excellent resource for engineers working in the area of heat transfer engineering. (
  • 2) I have worked on few turbulence models concerning natural convection and have found v2f model to be most suitable. (
  • Especially in a design stage, understanding natural convection inside the headlamp will make it possible to shorten its development period, which can be fulfilled by Computational Fluid Dynamics (CFD). (
  • Analysis of Natural Convection inside an Automotive Headlamp by Using CFD - Temperature Prediction of the Parts by SHT Method," SAE Technical Paper 2001-01-0860, 2001, . (
  • Nonlinear equations of the convection-diffusion type with nonlinear sources are used for the description of many processes and phenomena in physics, mechanics, and biology. (
  • In this work, we consider the family of nonlinear differential equations which are the traveling wave reductions of the nonlinear convection-diffusion equation with polynomial sources. (
  • It is shown that in the nonstationary case, both with and without account of convection, the general solution to the studied equations can be constructed under certain constraints on the parameters. (
  • Cell boundary element methods for convection-diffusion equations. (
  • Adaptive finite volume methods for steady convection-diffusion equations with mesh optimization. (
  • In this paper, we study finite volume element (FVE) method for convection-diffusion-reaction equations in a two-dimensional convex polygonal domain. (
  • 4] Kirane M. , Qafsaoui M. , On the asymptotic behavior for convection-diffusion equations associated to higher order elliptic operators under divergence form , Rev. Mat. (
  • Buoyant convection begins at the level of free convection (LFC) , above which an air parcel may ascend through the free convective layer (FCL) with positive buoyancy. (
  • On the other hand, when friction with the side walls or other mechanisms set up a convection roll pattern inside the vibrated container, we found that the convective motion immediately takes over as the dominant mechanism for size separation. (
  • Convective flow may be transient (such as when a multiphase mixture of oil and water separates) or steady state (see Convection cell). (
  • Discrete convective cells in the atmosphere can be identified by clouds, with stronger convection resulting in thunderstorms. (
  • Convection is often categorised or described by the main effect causing the convective flow, e.g. (
  • Some phenomena which result in an effect superficially similar to that of a convective cell may also be (inaccurately) referred to as a form of convection, e.g. thermo-capilliary convection and Granular convection. (
  • In contrast, the deep tropics are less disturbed by such synoptic weather variability, and can be idealized as a region, where the radiative cooling is balanced by randomly distributed moist convection, called radiative-convective-equilibrium. (
  • This allows for a smooth transition between the only two states (convection on and convection off) allowed in standard convective adjustment schemes. (
  • The procedure also predicts the generation of correlations between temperature and salinity and the presence of convectively induced upgradient fluxes that have been obtained in numerical simulations of heterogeneous convection and that cannot be represented by standard convective adjustment schemes. (
  • Atmospheric convection is the result of a parcel -environment instability, or temperature difference, layer in the atmosphere. (
  • A necessary (but not sufficient) condition for convection is that the environmental lapse rate (the rate of decrease of temperature with height) is steeper than the lapse rate experienced by a rising parcel of air. (
  • Forced convection involves the transport of fluid by methods other than that resulting from variation of density with temperature . (
  • This process, referred to as free convection , occurs when the environmental lapse rate (the rate of change of an atmospheric variable, such as temperature or density, with increasing altitude) of temperature decreases at a rate greater than 1 °C per 100 metres (approximately 1 °F per 150 feet). (
  • Thermal convection can be demonstrated by placing a heat source (e.g. a Bunsen burner) at the side of a glass filled with a liquid, and observing the changes in temperature in the glass caused by the warmer fluid circulating into cooler areas. (
  • Auto Convect mode, available on all Whirlpool ® Convection Microwaves, automatically adjusts time, temperature and power for common foods. (
  • Figure 1: Snapshots and vertical temperature structure for the different regimes of convection. (
  • Figure 4: Critical density contrast Δρ/ρ calculated from equation (2) as a function of the temperature difference Δ T driving convection. (
  • Mechanical convection technology provide unsurpassed temperature uniformity and stability to ensure fully reproducible results. (
  • Mechanical convection ensures fast heat-up and uniform temperature throughout the chamber for greater drying efficiency. (
  • The air is in a range of temperature of 16-39° C (289-312 K). I easely modeled the dispersion without convection. (
  • The team's new finding specifies the way that the temperature of a gas or liquid varies with the distance from a heat source during convection. (
  • The convection-cooled units deliver 300W continuous output power over a -40°C to 85°C temperature range without derating. (
  • Movement, or convection, in this layer is also responsible for all of Earth's volcanic and seismic activity. (
  • Convection cells can form in any fluid, including the Earth's atmosphere (where they are called Hadley cells), boiling water, soup (where the cells can be identified by the particles they transport, such as grains of rice), the ocean, or the surface of the sun. (
  • What are the steps of the convection cycle in Earth's atmosphere? (
  • Olson,P., Silver,P. G. & Carlson,R. W. The large scale structure of convection in the Earth's mantle. (
  • HS-ESS2-3 Develop a model based on evidence of Earth's interior to describe the cycling of matter by thermal convection. (
  • In the sense that the flow can be reversed to go in the opposite direction, so can mass transport by convection. (
  • Plasma: At any given time, the surface of the sun has thousands of roiling convection cells as large as the entire earth. (
  • When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. (
  • Thermal convection. (
  • Convection usually requires a gravitational field, but in microgravity experiments, thermal convection has been observed without gravitational effects. (
  • A.Gaponenko and V. E. Zakhvataev,Nonboussinesq Thermal Convection in Microgravity under Nonuniform Heating Albert Irvin Frye (1913). (
  • Pattern evolution during thermal convection in a mixture of two silicone oils, with viscosities 1cs and 100cs. (
  • Researchers from Tokyo Metropolitan University, have recently discovered unusual thermal convection in a uniform mixture of high- and low-viscosity liquids. (
  • Kobayashi and Kurita found that concentration fluctuations are enhanced by thermal convection when the two liquids have a large viscosity difference. (
  • When a fluid is heated from below, thermal convection is usually driven by a density difference. (
  • Kobayashi and Kurita found that immobile regions are transiently formed during thermal convection in well-mixed two component liquids with a large viscosity difference. (
  • The research group of Kazuya U. Kobayashi (PhD student) and Rei Kurita (Associate Professor) specializes in experimental studies of thermal convection. (
  • Prof. Kurita notes that "although this unusual phenomenon is only observed in thermal convection , the viscosity difference between components should play an important role in the dynamics of fluid mixtures, such as in mantle convection , mixing processes, etc. (
  • Kazuya U. Kobayashi et al, Ubiquitous transient stagnant domain formation during thermal convection in a well-mixed two component fluid with large viscosity difference, Scientific Reports (2017). (
  • As active cooling becomes increasingly important for today s high-speed memory solutions, OCZ developed the XTC Cooler for effective heat management of OCZ s proprietary XTC (Xtreme Thermal Convection) modules. (
  • Note that the term convection in heat transfer usually refers to the combination of heat transfer by conduction and advection, where advection refers to heat transfer due to bulk fluid motion. (
  • Heat Transfer- conduction, convection, and radiation practice that involves reading comprehension and application! (
  • Students will complete one mini lab on each type of heat transfer (radiation, convection and conduction). (
  • Simplified flow chart to help students identify the three types of heat transfer: radiation, convection and conduction. (
  • The concepts of conduction, convection, and radiation are covered as well as the laws of conservation of energy and matter. (
  • This web-quest includes two video clip links and a link to a student friendly website to obtain information on winds, air pressure, radiation, convection, and conduction. (
  • I figure I should take 2 things into account, the convection and the conduction. (
  • Moist convection leads to thunderstorm development, which is often responsible for severe weather throughout the world. (
  • Granular convection is a phenomenon where granular material subjected to shaking or vibration will exhibit circulation patterns similar to types of fluid convection . (
  • Under experimental conditions, granular convection of variously sized particles has been observed forming convection cells similar to fluid motion. (
  • [3] [4] The convection of granular flows is becoming a well-understood phenomenon. (
  • According to Heinrich Jaeger , "[this] explanation for size separation might work in situations in which there is no granular convection, for example for containers with completely frictionless side walls or deep below the surface of tall containers (where convection is strongly suppressed). (
  • Its counterpart in the ocean (deep convection downward in the water column) only occurs at a few locations. (
  • Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). (
  • Convection occurs on a large scale in atmospheres, oceans, planetary mantles, and it provides the mechanism of heat transfer for a large fraction of the outermost interiors of our sun and all stars. (
  • In the field of fluid dynamics, a convection cell is the phenomenon that occurs when density differences exist within a body of liquid or gas. (
  • An international team of physicists, led by Physics Professor Guenter Ahlers, is working to ascertain more about the fundamental physical laws that are at work in a process known as convection, which occurs in a boiling pot of water as well as in the turbulent movement of the liquid outer core of the Earth. (
  • Fluid convection (bulk flow) which occurs in the brain interstitial fluid under normal conditions ( 1 ) with vasogenic edema ( 2 ) and after infusion of solutions directly into brain parenchyma ( 3 ), is a promising technique for distribution of solutions into brain tissue. (
  • This particular type of convection, where a horizontal layer of fluid is heated from below, is known as Rayleigh-Bénard convection. (
  • Previous convection-based clinical trials showed significant diversity in the extent of convection among patients and drugs. (
  • After accounting for these variables, initial clinical experience shows that there is significant variability in the extent of convection among patients, as well as in differential tumor response to the therapeutic drugs. (
  • Therefore, increasing tumor response to convection-based therapies in a reliable/reproducible manner is essential, as well as real-time, noninvasive monitoring of the extent of convection and its early effects on the tissue. (
  • Achieve unrivaled performance with the only system that delivers top-down true convection for consistent results on special-occasion favorites, such as roasts, chicken, turkey and more. (
  • [2] While less dynamically important than in the atmosphere, such oceanic convection is responsible for the worldwide existence of cold water in the lowest layers of the ocean. (
  • Thermochemical convection can thus reconcile the survival of geochemically distinct reservoirs with the small amplitude of present-day density heterogeneities inferred from seismology and mineral physics. (
  • To understand the forms that convection might take in such a mantle, I have conducted laboratory experiments on thermochemical convection in a fluid with stratified density and viscosity. (
  • Moreover, quantitative scaling laws derived from the experiments show that the mantle might have evolved from strictly stratified convection 4 Gyr ago to doming today. (
  • Morgan,W. J. Plate motions and deep mantle convection. (
  • Such mixtures are ubiquitously observed in nature, daily life, and manufacturing processes e.g. mantle convection, syrup, polymer products. (
  • This suggests that the viscosity difference plays an important role in non-equilibrium phenomenon in fluid mixtures, such as in the dynamics of convection in the mantle, mixing processes in polymer solutions, etc. (
  • The UNAVCO IDV is an excellent way to show and explore mantle convection models, in map or globe views, with time animation. (
  • provided the mantle convection model output used in these examples, in 2006. (
  • Albarède, F. , and R. D. van derHilst ( 1999 ), New mantle convection model may reconcile conflicting evidence , Eos Trans. (
  • Albarède, F. , Time-dependent models of U-Th-He and K-Ar evolution and the layering of mantle convection , Chem. (
  • The SPM is implemented in a single-column model and compared with a large-eddy simulation of deep convection. (
  • An adaptive multigrid strategy for convection diffusion problems. (
  • For the solution of convection-diffusion problems we present a multilevel self-adaptive mesh-refinement algorithm to resolve locally strong varying behavior, like boundary and interior layers. (
  • An optimal-order error estimate for a family of characteristic-mixed methods to transient convection-diffusion problems. (
  • In this paper we propose and analyze stable variational formulations for convection diffusion problems starting from concepts introduced by Sangalli. (
  • In this paper, we extend the method to convection-diffusion problems. (
  • Convection microwaves combine conventional microwave technology with an extra heating element and fan, allowing you to bake, roast and crisp food along with general quick reheating. (
  • In a convection microwave, an extra heating element and fan circulate hot air around the cavity, letting you bake and roast food with home-cooked results. (
  • Convection is the only one of the three heat transfer methods to involve the movement of matter. (
  • Rayleigh-Bénard convection (RBC) is the buoyancy-driven flow of a fluid heated from below and cooled from above. (
  • Buoyancy and convection play no roll in the atmosphere. (
  • It was found that low-viscosity infusates tend to backflow along the catheter track, whereas high-viscosity infusates tend to form efficient convection. (
  • This convection microwave oven's stainless steel cavity allows better reflection and uniformity of heating inside the cavity so food cooks better. (
  • We understand convection as mass transport due to the average velocity of all molecules, and diffusion as mass transport due to the instantaneously varying, randomized velocity of individual molecules, compared to the average velocity of the fluid as a whole. (
  • This simple equation illuminates the consequence of convection: The mass of a species, distributed in space according to some concentration profile, is displaced according to the velocity, u . (
  • For the laminar case, since convection transports mass only tangent to the velocity - that is, along streamlines - it cannot lead to mass transfer between adjacent layers of fluid. (
  • Hauke Schulz and Prof. Bjorn Stevens, researchers in the department "The Atmosphere in the Earth System" at the Max Planck Institute for Meteorology (MPI-M), show in their new study in the Journal of Atmospheric Science the first observational evidence of mechanisms, previously hypothesized based on modelling studies, leading to the self-aggregation of convection. (
  • Gases: The atmosphere and weather are affected by convection. (
  • 8] W. Dahmen , S. Müller and T. Schlinkmann , On an adaptive multigrid solver for convection-dominated problems , SIAM J. Sci. (
  • Industrial Microwave Convection Oven's scope of application: rotary drum dryers are widely used in food, feed, chemical, pharmaceutical, mining and other industries. (
  • It consists of two primary convection cells, the Hadley cell and the polar vortex, with the Hadley cell experiencing stronger convection due to the release of latent heat energy by condensation of water vapor at higher altitudes during cloud formation. (
  • The size of convection cells is largely determined by the fluid's properties. (
  • Convection cells can even occur when the heating of a fluid is uniform. (
  • Play media The Sun's photosphere is composed of convection cells called granules, which are rising columns of superheated (5,800 °C) plasma averaging about 1,000 kilometres in diameter. (
  • It's cool to be dense-just watch these convection cells. (
  • Visualize the fluid motion of convection cells. (
  • When the pan is placed on the hot plate, convection cells rise through the liquid directly above the heating element (or coins, if you used them). (
  • This causes the convection cells to widen and become extremely well defined. (
  • These dark lines show where the fluid of one or more convection cells is diving downward. (
  • Liquids: Convection cells occur in liquids great and small, from a cup of coffee to the oceans. (
  • This continuous cycle of expansion and contraction causes convection cells. (
  • A state of bacterial magneto-convection results wherein bacterial plumes emerge spontaneously perpendicular to the wall and develop into stable and reproducible self-sustained flow convection cells. (
  • long lived convection cells. (
  • Heat emitted by electronic components within the device housing creates airflow by convection, which causes air to be drawn into the stand through the stand air intake openings and communicated into the device air intake openings. (
  • With a gentle airflow, our gravity convection incubators allow a heat-generated convection to move the air vertically through the chamber to heat samples. (
  • The broader sense is in fluid mechanics, where convection refers to the motion of fluid driven by density (or other property) difference. (
  • For intermediate density contrasts, a 'doming' regime of convection is observed, in which hot domes oscillate vertically through the whole layer while thin tubular plumes rise from their upper surfaces. (
  • We consider a nonlocal convection-diffusion equation $u_t=J*u-u-uu_x,$ where $J$ is a probability density. (
  • If there is bulk fluid motion, convection will also contribute to the flux of chemical species. (
  • We have a range of microwaves from some of the best brand names in the industry, whether you are looking for a Panasonic microwave, a Westinghouse microwave, Samsung microwave, a Bosch microwave or a Sharp convection microwave. (
  • A combination machine like the convection microwave has expanded cooking capabilities, and anyone who ponies up for one of these puppies should know whether or not something like foil can be used inside it. (
  • Roasting, baking, cooking and crisping are all possible when you upgrade to a convection microwave. (
  • In the numerical simulation below, the fluid is at rest in the bulk until convection rolls appear which in turn are destabilzed by finger-like structures that detach from the boundary layers, called plumes. (
  • In the present work we derive analytical solutions for the problem of convection, diffusion and chemical reaction in wall-flow monoliths. (
  • According to the University of Illinois at Urbana-Champaign, convection refers to the distribution of heat through vertical motions of air. (
  • Convection motions within the Sun transport heat from its interior to its surface. (
  • Eventually these formations trigger the breakdown of the convection rolls and the motion becomes chaotic/turbulent. (
  • Convection works by transferring heat from a hot substance to a cooler one through the motion of one of the substances. (
  • Convection is mass transfer due to the bulk motion of a fluid. (
  • On astronomical scales, convection of gas and dust is thought to occur in the accretion disks of black holes, at speeds which may closely approach that of light. (
  • Convection cannot take place in most solids because neither bulk current flows nor significant diffusion of matter can take place. (
  • A convection cell is most notable in the formation of clouds with its release and transportation of energy. (
  • It is demonstrated that in the steady-state case without account of convection, the general analytical solution can be found without any constraints on the equation parameters and it is expressed in terms of the Weierstrass elliptic function. (
  • Mehdi Dehghan, "On the numerical solution of the one-dimensional convection-diffusion equation," Mathematical Problems in Engineering , vol. 2005, no. 1, pp. 61-74, 2005. (
  • In this paper, we answer the question under which conditions the porous-medium equation with convection and with periodic boundary conditions possesses gradient-type Lyapunov functionals (first-order entropies). (
  • This is the convection equation , a time-dependent, first-order partial differential equation. (
  • Plasma is ionized and massy particles, convection of which is the Sun's major heat transport mechanism. (
  • Convection is known to depend on variables such as catheter size, flow rate, tissue consistency, catheter localization, infusate concentration, and molecular weight ( 12 , 13 ). (
  • Check out Spectrum Chemical's wide selection of gravity convection incubators ideal for routine general cell culture protocols that call for open plates or open containers. (
  • The convection may be due to gravitational, electromagnetic or fictitious body forces. (
  • Convection , process by which heat is transferred by movement of a heated fluid such as air or water. (
  • Convection is the transfer of heat by the movement of a heated fluid. (
  • The BINDER incubator of the BF Avantgarde.Line series with forced convection is suitable for all gentle incubation applications, particularly under a full load and large batch throughputs. (
  • There are a few general archetypes of atmospheric instability that are used to explain convection (or lack thereof). (
  • Atmospheric convection is called deep when it extends from near the surface to above the 500 hPa level, generally stopping at the tropopause at around 200 hPa . (
  • Some more localized phenomena than global atmospheric movement are also due to convection, including wind and some of the hydrologic cycle. (