Multiple solutions in magnetohydrodynamic stagnation flow of hybrid nanofluid past a sheet with mathematical chemical reactions model and stability analysis

The homogeneous heterogeneous reactions (H-H reactions) in the magnetohydrodynamic (MHD) boundary layer stagnated flow of an Al2O3-Cu-water base hybrid nanofluid past a stretching shrinking sheet are studied. A newly developed two-phase hybrid nanofluid model based on Buongiorno's model is used to understand the nanofluids behaviors. Multiple solutions are observed for specific ranges of various parameters, whose stabilities are checked and discussed, which seem to have been neglected in previously published articles about studies of MHD-stagnation flow and mathematical chemical reactions models using hybrid nanofluid. The heterogeneous reaction considered in this case is isothermal and first order, whereas the homogeneous chemical reaction is isothermal cubic autocatalytic. The solutions so captured are examined using various graphs to demonstrate the impact of different physical parameters, and their physical insights are also given. The results show that hybrid nanofluids, which have distinct functions in the processes of homogeneous and heterogeneous reactions, play a key role in the homogeneous-heterogeneous reactions' transport mechanism. The quadratic multiple regression analysis evaluations of the local Nusselt number demonstrate that the thermophoretic impact predominates over Brownian motion for both magnetic and non-magnetic effects.

Automated summary

This study investigates the homogeneous-heterogeneous reactions in the magnetohydrodynamic boundary layer stagnated flow of an Al2O3-Cu-water base hybrid nanofluid. A newly developed two-phase hybrid nanofluid model is used to understand the nanofluid behaviors. The results show that hybrid nanofluids play a key role in the transport mechanism of the homogeneous-heterogeneous reactions.