Impact of hybrid nanofluids on unsteady MHD flow and heat transfer due to a moving infinite vertical plate

The objectives of this study are (i) to find exact analytical solutions to the unsteady hybrid nanofluid flow and heat transfer due to a moving infinite flat plate, and (ii) to investigate the impacts of different hybrid nanofluids (Cu-Al2O3/water, CuO-Al2O3/water, and Ag-Al2O3/water) on the unsteady flow and heat transfer characteristics with MHD and variable temperature. The Laplace transform technique is employed to find the exact analytical solutions of the partial differential equations with appropriate boundary conditions governing the problem considered. The results computed for engineering quantities, namely skin friction coefficient and Nusselt number and velocity and temperature profiles by the Laplace transform technique are analyzed using graphs and tables. It has been found that there is a significant increase in the heat transfer rate for hybrid nanofluids than for nanofluids and we observed a higher heat transfer rate for Cu-Al2O3/water and a lower heat transfer rate for Ag-Al2O3/water than for the others. The novelty of this study is finding an exact analytical solution to the problem of hybrid nanofluid flow due to moving vertical plate where the effects of magnetic field and variable plate temperature conditions are considered. The obtained results can be used in various engineering applications, including geothermal reservoirs, packed-bed storage tanks, packed-bed catalytic reactors, thermal insulation, grain storage, porous solids drying, and petroleum resource gas production. Furthermore, the findings can be used to validate numerical solutions for more complex transient hybrid nanofluid flow and convective heat transfer problems.