Lattice BGK simulation of hydromagnetic double-diffusive convection in a rectangular enclosure with linearly variable temperature and concentration gradients

摘要

Hydromagnetic double-diffusive convection of a binary gas mixture is simulated by a temperature-concentration latitce Bhatnagar-Gross-Krook (TCLBGK) model in a rectangular enclosure with the top and bottom walls being insulated,while linearly variable temperature or concentration gradient or both are imposed along the left and right walls from the bottom to the top and a uniform magnetic field is applied in x-direction.we take the Prandtl number Pr =1,the Lewis Le=2,the thermal Raleigh number RaT =105,the Hartmann number Ha =0,25,50,the dimensionless heat generation or absorption Φ =0,the aspect ration A =2 for the enclosure and the ratio of buoyancy forces N =0.8,1.3.Numerical results are discussed in detail.It is founded that linearly variable temperature and concentration gradients have significant influence on the stratification and direction of streamlines and convection.