Transient thermosolutal convection of Boussinesq fluid with moving heating and cooling blocks in a square cavity

Transient thermosolutal convection of Boussinesq fluid with moving heating and cooling blocks placed at the bottom wall in a square cavity was numerically investigated subject to vertical gradient of thermosolutal conditions at the top or bottom walls. With the progress in time, due to the interactions among thermal and solutal buoyancy and stratification together with forced block movement, a complex flow structure was formed in the cavity as well as the corresponding transient heat and mass transports. At steady state, the absolute values of average Nusselt and Sherwood numbers remained almost constant with time as an increase of the velocity of the blocks. Furthermore, the cooling phase took more time than heating phase to reach the steady state, and time to reach the steady state decreased as an increase in the moving velocity of the block.