Heat transfer: a review of 2002 literature

Unsteady thermal gravitational-capillary convection in a rectangular cavity with sudden heating of one of the vertical walls by electric current was experimentally investigated. The development in time of the spatial form of ethyl alcohol flows with the Prandtl number Pr = 16 at 20°C was studied. The development of the hydrodynamic boundary layer on the heated wall and the flow along the free surface of a liquid layer was examined. The profiles of the vertical and horizontal velocity components were measured during the development of boundary layers and flow in a volume of liquid. Evolution of temperature fields on the free surface of a liquid layer was studied using a thermal imager.

Development of unsteady convection in a rectangular cavity with sudden heating of a vertical wall

The development of a convective flow after sudden heating of a vertical wall that laterally bounds a layer of ethyl alcohol in a system consisting of vertical layers of alcohol and air, separated by a thin metal partition, is studied numerically in a conjugate problem statement. The equations of thermogravitational convection in the Boussinesq approximation, written in variables of temperature, vortex, and stream function, are solved by the finite element method. The development of unsteady hydrodynamic and thermal boundary layers on all four vertical walls is studied. The temperature fields in liquid, gas and in a vertical partition are calculated. The features of the development of the spatial form of the flow and unsteady conjugate convective heat transfer between the layers of liquid and gas affect significantly the unsteady temperature fields and temperature gradients in a thin metal partition. The maximum temperature gradients in the partition appear at the initial stage of flow development.

Numerical studies of nonstationary conjugate convective heat transfer in vertical layers of liquid and gas separated by a thin metal partition

A flow in the near-wall region with free convection in a temperature-stratified medium is analyzed. A laminar flow in a plane square domain and laminar and turbulent flows near a plate are considered in the cases of linear and nonlinear stratifications. Different nonstationary stages of the flow and a local self-similar regime with criterion for its realization are distinguished. General characteristics for the laminar and turbulent regimes are formulated.

Specific features of wall free convection in a temperature-stratified medium

Based on the analytical solution of the problem about the temperature distribution in an infinite rib with a discontinuous distribution of the heat exchange coefficient on the rib surface upon uniform displacement of the rib with respect to the discontinuity, the effect of heat transfer by heat conductivity along the rib on the longitudinal temperature distribution is studied. The conditions of applicability of the results obtained are analyzed.

The effect of longitudinal heat flow on the temperature distribution in a moving rib for a discontinuous distribution of the heat transfer coefficient

The natural-convective heat transfer is studied in a vertical cylindrical tank with a heat-conducting wall. It is demonstrated that the theory of local self-similarity may be applied in the case of a uniform heat supply to the side wall in the quasi-stationary mode for a free-convective boundary layer. This theory enables one to derive simple analytical formulas for some hydrodynamic and thermal characteristics. The analytical results are compared with the numerical simulation results. The effect of the wall thermal conductivity on the heat-transfer processes in the mode of convection development is investigated numerically under conditions of short heating times.

Theoretical Investigation of the Effect of the Thermal Conductivity of a Wall on the Processes of Free-Convective Heat Transfer in a Vertical Cylindrical Tank

S. G. Cherkasov

Papers

Theoretical Investigation of the Effect of the Thermal Conductivity of a Wall on the Processes of Free-Convective Heat Transfer in a Vertical Cylindrical Tank