THREE-DIMENSIONAL SIMULATION OF HEAT AND MASS TRANSFER BY THE HYBRID LATTICE BOLTZMANN METHOD

A hybrid model has been developed to analyze the process of joint mass and heat transfer in a three-dimensional formulation. The fl ow velocity was calculated using the mesoscopic lattice Boltzmann equations, and the temperature and concentration fi elds were obtained by fi nite-diff erence solution of the macroscopic energy and diff usion equations. Numerical studies were performed by varying the Rayleigh and Lewis numbers and of the ratio of lift forces (BR) due to temperature and concentration gradients. It is established that at BR ≤ 0 and BR ≥ 2 stratifi ed concentration and thermal fi elds are formed in the cubic cavity. Three fl ow regimes are distinguished depending on BR: quasitwo-dimensional, three-dimensional nonstationary and two-dimensional. Correlation formulas are proposed for calculating the average Nusselt and Sherwood numbers.
   
Author:  A. É. Nee
Keywords:  method of lattice Boltzmann equations, fi nite diff erence method, natural convection, mass transfer
Page:  585