THERMAL AND SOLUTAL BUOYANCY EFFECTS ON MIXING OF OPPOSED LAMINAR JETS IN A TWO-DIMENSIONAL PASSIVE MIXER AT A HIGHER REYNOLDS NUMBER

Numerical analysis of two opposing streams of different fluids having different temperatures (same phase, miscible) in a 2-D adiabatic channel, is numerically investigated in the mixed convection laminar flow regime. The thermal and solutal buoyancy effects in aiding configuration (upper jet heavy and lower jet hot) have been considered through the Boussinesq approximation. Hasan & Khan [7] investigated in detail the effect of variation of Richardson numbers on flow dynamics & mixing of streams at Re = 200. It is decided to carry out numerical experiments at higher Re (Re = 400) and with three combinations of thermal Richardson number (RiT) & solutal Richardson number (RiC) namely, (0.5, 1), (1, 0.5) & (1, 1). Within the parametric space of the present study, unsteady, oscillatory periodic flow with vortex shedding is obtained for all conditions. The combined value of Richardson numbers (RiT + RiC) effect the flow and mixing rather their individual values. With higher combined value of Richardson number better mixing is achieved in shorter mixing lengths.