Hybrid nanofluid flow induced by an exponentially shrinking sheet

The flow and heat transfer induced by an exponentially shrinking sheet with hybrid nanoparticles is investigated in this paper. The alumina (Al2O3) and copper (Cu) nanoparticles are suspended in water to form Al2O3-Cu/water hybrid nanofluid. In addition, the effects of magnetohydrodynamic (MHD) and radiation are also taken into account. The similarity equations are gained from the governing equations using similarity transformation, and their solutions are obtained by the aid of the bvp4c solver available in Matlab software. Results elucidate that dual solutions exist for suction strength S > S-c and shrinking strength lambda > lambda(c). The critical values S-c and lambda(c) for the existence of the dual solutions decrease with the rising of the solid volume fractions of Cu, phi(2) and the magnetic parameter, M. Besides, the skin friction and the heat transfer rate increase with the increasing of phi(2) and M for the upper branch solutions. The increasing of radiation, R leads to reduce the surface temperature gradient which implies to the reduction of the heat transfer rate for both branches when lambda < 0 (shrinking sheet). The stability of the dual solutions is determined by the temporal stability analysis, and it is discovered that only one of them is stable and physically applicable.