heat and mass transfers on the chemically reactive thermosolutal convective flow of rivlin-ericksen fluid over a porous medium with viscous dissipation effect

Chemically reacting flows of non-newtonian fluids through porous media have numerous medical and industrial applications, including targeted drug delivery, polymer processing, and extrusion operations. in these contexts, convective heat transfer is a critical mechanism that must be accurately predicted. this article analyzes the thermosolutal convection of a chemically reactive rivlin-ericksen fluid in a porous medium, accounting for viscous dissipation, using both linear and nonlinear stability approaches. the nonlinear analysis is performed using a truncated fourier series method, while the linear stability is examined via the normal mode technique. it is found that oscillatory convection occurs only when the solutal rayleigh-darcy number is negative. the range of this number that allows oscillatory convection depends on several physical parameters. an increase in the rivlin-ericksen parameter, the modified heat capacity ratio, and the péclet number reduces this range, whereas a higher lewis number expands it. moreover, the lewis number, solutal rayleigh-darcy number, and gebhart number accelerate the onset of convective waves, while the rivlin-ericksen parameter and the modified heat capacity ratio delay it. additionally, both convective heat and mass transfer rates decrease with increasing rivlin-ericksen parameter and modified heat capacity ratio, but they increase with higher values of the thermal and solutal rayleigh-darcy numbers, the lewis number, the chemical reaction parameter, the péclet number, and the gebhart number.