Numerical comparative study of squeezing couple–stress hybrid nanofluid (SiO 2 +Al 2 O 3 /blood) with heat source/sink and activation energy

Abstract

This numerical study investigate the heat and mass transfer behavior in among heat generation (Q^*>0) and absorption (Q^*<0) of unsteady incompressible couple–stress magnetohydrodynamic (MHD) hybrid nanofluid flow through a horizontal squeezed channel, taking into account the combined effects of chemical reaction and activation energy. The SiO₂ + Al₂O₃/blood hybrid nanofluid offers excellent heat transfer and biocompatibility, making it highly suitable for biomedical, pharmaceutical, and diagnostic applications with great scope in healthcare advancements. This fluid is a non-toxic, customized drug that improves blood circulation and reduces side effects. Applying similarity transformations to the governing PDEs reduces them to a set of ODEs. Using the fourth-order Runge–Kutta scheme, the shooting method, along with relevant boundary conditions, is employed to solve these equations. The effects of various dimensionless parameters on temperature and concentration distributions are sketched to explain. We conclude that in both heat absorption and generation cases, the concentration distribution decreases for all dimensionless parameters but increases with activation energy. In contrast, temperature distribution follows an opposite trend. The skin friction number (C _f ), Nusselt number (Nu _x ), and Sherwood number (Sh _x ) are investigated numerically. When the magnetic parameter increases from 1 to 3, skin friction rises by 4.96% for both heat generation and absorption cases. The Schmidt number is increased by heat generation (Q^*>0) and 12.26% heat absorption (Q^*<0) as Sc is increased by 1–1.2. As the couple stress parameter rises from 0.1 to 0.3, skin friction decreases sharply by 33.56% in both cases, whereas the Nusselt number increases by 17.24% heat generation (Q^*>0) and 20.77% heat absorption (Q^*<0). An increase in the Eckert number of Ec = 0.01–0.03 raises the Nusselt number by 14.32% and 17.17%, respectively. The obtained similarity solutions closely match previously published results.