Limit of the buoyancy ratio in Boussinesq approximation for double-diffusive convection in binary mixture

This paper deals with a mathematical and numerical investigation of double-diffusive natural convective heat mass transfer in cavity filled Newtonian fluid significant density diffusivity changes. In such situation, the assumption Boussinesq approximation is not justified, an appropriate model based on set Low Mach Number equations used. The active parts two vertical walls are maintained at fixed but different temperatures concentrations, while other walls, as well inactive areas sidewalls, considered to be adiabatic impermeable transfer. coupled momentum, energy, solute binary mixtures ideal gases solved through global iterative procedure finite volume methods context low number approximation. study includes effect buoyancy ratio N aim find its application limit conditions. results show that if we use convection, value parameter must between ?6 27.