Hybrid Approach to Modeling the Process of Convective Radiative Heat and Mass Transfer in Closed Differentially Heated Cavities

A hybrid model has been developed for the analysis of the process of combined mass and heat transfer in closed rectangular cavities under the conditions of volumetric radiation of a medium. Within the framework of the formulated method, hydrodynamics is described by the mesoscopic lattice Boltzmann method, and the macroscopic equations of energy and concentration are described by the method of finite differences. To calculate the radiation flux, use was made of approximation of an optically thick layer. Based on the results of mathematical modeling, it has been established that accounting for radiation heat transfer results in an increase of the incidence angle of thermal stratification and the formation of external secondary flows. The convective Nusselt number decreases as the radiation parameter rises. On the other hand, it has little effect on the mass transfer rate.