Simulation of turbulent heat transfer in application to natural-convection wall flow

As a result of analysis of experimental data for developed turbulent natural-convection flow on a vertical heated plate, algebraic models are suggested of turbulent thermal diffusivity and turbulent viscosity for the inner and outer regions. The parameters of the models are determined by comparing the experimental data with the results of calculations using the equations of natural-convection boundary layer. Relevant approximations are given in the form of functions of the value of the ratio between the thermal and dynamic scales of velocity. Comparison is made of the experimentally obtained and calculated profiles of temperature and velocity in the neighborhood of the wall. As a result of calculations using the suggested model, the inference is made of the need to use the model of turbulent temperature diffusivity in problems of this class along with the model of turbulent viscosity.