Transverse temperature

Effect of Thermal Boundary Conditions. When the side walls are cooled instead of being insulated, there is no critical Rat number, and any transverse temperature gradient will lead to a buoyancy-driven secondary flow. Compared with the previous example (Figure 8b), the rolls are reversed and now rotate outward. These examples demonstrate the strong influence of the thermal boundary conditions on CVD reactor flows. 

To test the fit of the theoretical mechanism to the experimentally observed phenomena, it seemed principally important to try to realize experimentally the second mode of the autowave process. Its initiation was performed, in accordance with the theory, not by pulse heating but with the help of a heater whose temperature could be raised slowly. Under such conditions the slower wave could not be excited either in liquid helium or nitrogen, that is, there was only one mode of wave propagation. This was possibly connected with the fact that under conditions of intense heat release into liquid media, high (close to critical) transverse temperature gradients occurred in the samples, which might be a source of severe disturbances impeding the realization of the slower wave mode. 

Joule heat generated by the ionic current is removed through cooling jackets mounted on the transverse walls. This creates a transverse temperature gradient which drives a stable and usually deleterious convective flow (3). Furthermore, the axial temperature gradient in the thermal entrance region (10,11) near the tips of the electrodes may drive a buoyancy instability when the thermal gradient exceeds a critical value (4,12). Apart from the physical properties of the carrier fluid, the critical temperature... 

R. Thorsen and F. Landis, Friction and Heat Transfer Characteristics in Turbulent Swirl Flow Subject to Large Transverse Temperature Gradients, 1 Heat Transfer (90) 87-98,1968. 

Measured inflame transverse temperature profiles in propane flames at R = 105,211-24,1996.)... 

The heat is generated within the whole volume of the solution, but is removed only through the walls of the separation column, thus resulting in a transversal temperature gradient. The temperature gradient is the reason of the thermal flow. In the unordered thermal flow the direction towards lower temperature predominates, and therefore particles are moved to places with lower temperature. For the thermal flow velocity it holds that... 

Nernst effect - The production of an electric field in a conductor subject to an applied magnetic field and containing a transverse temperature gradient. The electric field is perpendicular to the magnetic field and the temperature gradient. 

The Hall effect, first reported in 1879 by Hall, is by far the best known of the various galvanothermomagnetic effects. In this case, if an electrical current is made to flow in a conductor perpendicular to a magnetic field, in addition to the transverse temperature gradient due to the Ettingshausen effect, one also observes a transverse electric field which is perpendicular to both the electrical current and the magnetic field (Fig. Ic). The Hall coefficient is defined by... 

The transverse temperature gradient we are trying to produce by the Ettingshausen effect will tend to be thermally shorted out through the electrodes. 

Evaluation of the transverse temperature profile ( the thermal lens ) induced by laser radiation passing an absorbing (liquid) medium. Optical detection of organic compounds by the change of refractive index... 

Despite the small gap size, transverse temperature and concentration gradients may exist in microchannels. These gradients depend on the rates of heat and mass transfer versus the rate of reaction. Da, as discussed above, provides an estimate of transport effects but cannot be used for quantitative modeling. The Nusselt number (Nu) and Sherwood number (Sh) provide the heat and mass transfer coefficients, respectively, between a surface and the bulk gas, in the direction perpendicular to the flow. They are defined as ratios of heat or mass flux at the boundary to the net flux between the bulk and the surface ... 

T, lowest temperature reached with this species in a helium buffer-gas-based experiment. This temperature does not necessarily corespond to the maximum number or density given in the N, n, Fcolunms. In the case oftrapping this temperature indicates the lowest trapped temperature achieved. In the case of a beam, it generally indicates the transverse temperature of the beam. Results indicate wheth the molecules were just cooled or cooled and trapped, made into a beam, or made into a guided beam. 

We shall show here that if just two temperatures, chosen at "Lobatto points", are used to characterize the transverse temperature distribution in a laminar lubricating film, the effects of that distribution can be surprisingly well predicted. The calculations we have 80-far performed have been directed solely towards demonstrating this fact, and only rudimentary numerical methods have been used in the plane of the film. Accordingly, no meaningful computation times can yet be reported. But we believe the technique will prove to be quite suitable for practical calculations. 

In order to maintain an optimum efficiency of the catalyst, near-isothermal conditions for the reaction are necessary. This means that the longitudinal and transverse temperature gradients should be minimized. This can be... 

A transverse temperature gradient is undesirable, since the mobility of ions is temperature-dependent and the boundaries or bands would become curved and diffuse. This constitutes a limitation on the thickness of the electrophoretic medium. Sheets and layers are therefore most often used. Columns of circular cross-section, which are popular in the disc polyacrylamide-gel electrophoresis and as density-gradient columns, have a limited diameter. 

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