THREE TEMPERATURE MODEL FOR HEAT AND MASS TRANSFER IN NON-NEWTONIAN Cu-EG NANOFLUIDS EMBEDDED WITH PERMEABLE MEDIUM

In the current study, the impacts of local thermal non-equilibrium model and Cu-EG Oldroyd-B nanofluid layer on natural convective heat and mass transfer in a permeable medium are investigated. The transport equations are framed using modified Buongiorno two-phase Darcy model with different temperature profiles for fluid, particle, and porous-matrix phases. The thermophysical properties of the considered nanofluid are calculated using available experimental data. In the current situation, weak, non-linear analysis has been performed to find the Nusselt number and Sherwood number by solving finite amplitude equations using NDSolve in Mathematica 12.0. Influence of different parameters including viscoelastic parameters, LTNE parameters, thermal Rayleigh number, and nanoparticle volume fraction on heat and mass transfer mechanisms are explained graphically. An increase in the Nusselt number with the rising values of volume fraction of nanoparticles is registered and reach its maximum value at phi = 0.05 due to enhanced thermal conductivity. The significant findings for Oldroyd-B nanofluids are that the stress relaxation parameter declines heat transfer while strain retardation parameter promotes it. This study improves the theoretical understanding of heat transfer in porous media and facilitates the use of such theoretical models in practical applications.