Thermal analysis and entropy generation on time-dependent two-phase immiscible non-Newtonian nanofluids through porous tube under electromagnetic effects with slip velocity

Abstract

The present research scrutinized the numerical simulations on the thermal effects of multiphase flow of immiscible Sutterby-Jeffrey nanofluids in a circular cylinder along with slip velocity through the porous region. The influence of Palladium ($Pd$) nanoparticles with distinct shapes was studied, proceeding with hexahedron ($n_2=3.72$) shape. The conduit is maintained to be isothermal and the governing equations are constructed for the continuity, momentum, energy and entropy equations along with continuity in the interfacial regions. The different combinations of base fluids Ethylene Glycol and mineral oil are explained and it is certainly proven that Ethylene Glycol performs better than Mineral oil. The dimensionless equations governing each layer were numerically integrated using the finite difference method with the Crank–Nicolson approach. A mesh independence and validation results are conducted. Furthermore, a parametric study is performed under three conditional cases involving the Sutterby parameter, Grashof number, electromagnetic field, and Prandtl number. The comparison was made between $Pd$, $Ti{O}_2$ and $Au$ nanoparticles for the velocity profile and found that the effectiveness of Pd nanofluids was much more efficient than the Au and $Ti{O}_2$ nanofluids. A binate circumstance was observed in the Bejan number under conditional cases. Meanwhile, the Sutterby parameter and Jeffrey parameter enhanced the entropy generation. In addition, the entropy in region I was less compared to Region II whereas the opposite behaviour was perceived in the velocity profiles.