Unsteady MHD boundary layer stagnation point flow with heat and mass transfer in nanofluid in the presence of mass fluid suction and thermal radiation

Abstract

The unsteady boundary layer stagnation point flow of heat and mass transfer in a nanofluid with magnetic field and thermal radiation is theoretically investigated. The resulting governing equations are nondimensionalized and are transformed using a similarity transformation and then solved numerically by the shooting method. Comparison with the previously published work is presented and the results are found to be in good agreement. The effects of unsteadiness parameter A , solid volume fraction \( \varphi\), magnetic field M, radiation parameter R, Schmidit number Sc and suction parameter w on the fluid flow, heat and mass transfer characteristic are discussed. Dual similarity solutions for the velocity, temperature and concentration profiles are obtained for some negative values of the unsteadiness parameter. It is found that the critical values of A for which the dual solution exists depend on the values of solid volume fraction parameter in the presence of the Schmidit number. Also, the magnetic field parameter as well as the mass fluid suction widen the range of A for which the solution exists. The results also indicate that momentum, thermal and concentration boundary layer thickness for the first solution are thinner than that of the second solution.