Investigation of unsteady hydromagnetic natural convection flow with heat and mass transfer of a viscous, incompressible, electrically conducting, optically thick radiating and chemically reactive fluid past an infinite vertical plate with Newtonian heating is carried out considering impulsive, accelerated and oscillatory movements of the free-stream. Exact analytical solutions for fluid temperature and species concentration are obtained using Laplace transform technique whereas solution for fluid velocity is obtained numerically using INVLAP routine of MATLAB software along with Laplace tranform technique. The numerical solutions for fluid velocity, fluid temperature and species concentration are displayed graphically whereas the numerical values of shear stress, rate of heat transfer and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. Comparison between the present numerical results and the carlicr published results is made and there is an excellent agreement between these results.
hydromagnetic natural convection, Newtonian heating, thermal radiation, chemical reaction, free-stream
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