Study of Double Diffusive Natural Convection Under Local Thermal Non-Equilibrium State and Different Heating and Salting Profiles Using Entropy Generation as an Analysis Tool

In the present study, the effect of different linear heating and salting profiles on the validity of the local thermal non-equilibrium (LTNE) approach within a cavity composed of two distinct layers, a porous layer and a clear binary fluid layer, is investigated numerically. Entropy generation is employed as an analysis tool, and simulations are performed using the finite volume method and an in-house FORTRAN code. The influence of several key parameters on internal irreversibility and the LTNE state is examined. These parameters include the heating and salting profiles, buoyancy ratio (N), dimensionless porous layer thickness, and the porosity of the porous layer (ε). It was observed that, depending on the temperature and concentration profile, a composite cavity with substantial porous layer thickness evolves into a significant source of entropy generation, exhibiting a particularly high level of LTNE between the two phases of the porous layer.