Soret-driven thermosolutal convection in bidispersive porous medium with vertical throughflow

This article investigates thermosolutal convection in bidispersive porous medium with Soret effect and vertical throughflow. The Oberbeck–Boussinesq approximation assumed and fluid flow obeys Darcy's law. Local thermal equilibrium is considered between solid and fluid phases. We analyze the system stability through linear instability, nonlinear stability (energy method), and weak nonlinear analysis. The expression for Ra is derived analytically, using the Galerkin orthogonalization technique. The Ginzburg–Landau equation is derived to get deep insight into convective amplitudes, also we explore the heat and mass transfer in the system by defining Nusselt and Sherwood numbers. The research delves into the influence of various physical parameters on the system's stability. The solutal Rayleigh number and Soret number have destabilizing property, whereas the Lewis number, momentum transfer coefficient, and permeability ratio have the stabilizing nature. The sub-critical region decreases as the Soret number increases. The strong buoyancy force delays the heat transfer and mass transfer by disrupting existing mass transfer. The critical Rayleigh number maintains symmetry over the upward and downward throughflow. The less area under the curve for average Nusselt and Sherwood number over permeability ratio implies total heat and mass transfer alleviating.