1636 Research Article International Journal of Current Engineering and Technology ISSN 2277 - 4106 © 2013 INPRESSCO. All Rights Reserved. Available at http://inpressco.com/category/ijcet Combined Radiation and Ohmic Heating Effects on MHD Free Convective Visco-Elastic Fluid Flow Past a Porous Plate with Viscous Dissipation M.Umamaheswar Ȧ , S.V.K.Varma Ḃ and M.C.Raju Ȧ* Ȧ Department of Mathematics, Annamacharya Institute of Technology and Sciences, Rajampet (Autonomous), A.P, India Ḃ Department of Mathematics, S.V.University, Tirupathi, A.P, India Accepted 04 November 2013, Available online 01 December 2013, Vol.3, No.5 (December 2013) Abstract In this paper, we investigated the combined radiation and Ohmic heating effects on MHD free convective Visco-elastic fluid flow past a porous plate with viscous dissipation. The governing equations are solved for the velocity profile, temperature and concentration by using double perturbation technique. The effects of magnetic parameter M, Grashof number Gr, modified Grashof number Gm on velocity u are shown in the graphs while the effects of these parameters on skin friction are numerically discussed through tables. Keywords: Grashof number; modified Grashof number; MHD; Ohmic heating; Visco-elastic fluid; viscous dissipation. 1. Introduction 1 The MHD viscous flow containing heat and mass transfer has attracted many researchers for its applications in various areas like power and cooling systems, cooling of nuclear reactor, magneto-hydrodynamic power generation systems.The effect of ohmic heating on the MHD free convective heat transfer has been studied for Newtonian fluid by Hossain (M. A. Hossain, 1992). Chen (Chien- Hsin-Chen, 2004) has studied the problem of combined heat and mass transfer of an electrically conducting fluid in MHD natural convection, adjacent to a vertical surface with Ohmic heating. The effect of Ohmic heating and viscous dissipation on MHD mixed convection heat and mass transfer about a vertical plate are calculated numerically by Aydin and Kaya (O. Aydin and A. Kaya, 2009). Siddappa (Siddappa et al. 185) discussed the flow of Visco elastic fluids of the type Walter’s liquid B past a stretching sheet. Andersson (H. I. Andersson, 1992) studied the flow problem of electrically conducting Visco elastic fluid past a flat and incompressible elastic sheet. Magyari (Magyari et al. 2004) investigated an analytical solutions for unsteady free convection in porous media. Lahurikar (Lahurikar et al. 1995) considered mass transfer effects on flow past a oscillating plate. Soundalgekar (Soundalgekar et al., 1997) gave an exact solution for magnetic free convection flow past an oscillating plate. Sreekanth (Sreekanth et al., 2001) discussed transient MHD free convection flow of an incompressible viscous dissipative fluid. Ganesan (Ganesan et al., 2002) studied radiation and mass transfer effects on fluid flow an *Corresponding author: M.C.Raju incompressible viscous fluid past a moving vertical cylinder. Rao (V.V.R. Rao, 1971) discussed the unsteady magnetohydrodynamic convection heat transfer past an infinite plane. Pop (I. Pop, 1969) has reported on transient buoyancy-driven convective hydrodynamics from a vertical plate. Beg (Beg et al., 2006) have analyzed the free convective MHD flow from a spinning sphere with impulsive motion using the Blottner difference method. Raptis and Massalas (A. Raptis and C. V. Massalas, 1998) studied induced magnetic field effects in their study of unsteady hydromagnetic-radiative free convection. Aziz (M. Abd-El Aziz, 2006) considered the thermal radiation flux effects on unsteady MHD microplar fluid convection. Rahman and Sarkar (M. M. Rahman and M.S.A. Sarkar 2004) have studied unsteady MHD flow of a dusty Visco- elastic oldroyd fluid under time varying body force through a rectangular channel. Makinde and Osalusi (OD. Makinde and E. Osalusi, 2006) have considered a MHD steady flow in a channel with a slip at permeable boundaries. Mishra (Mishra et al., 2008) investigated a flow and heat transfer of a MHD Visco-elastic fluid in channel with stretching walls. Takhar and Soundalgekar (V. M. Soundalgekhar and H. S. Takhar , 1992) discussed the effect of radiation on the natural convection flow of a gas past a semi-infinite plate using the Cogly-Vincentine- Gilles equilibrium model. Muthucumaraswamy (Muthucumaraswamy et al., 2009) studied unsteady flow past an accelerated infinite vertical plate with variable temperature and uniform mass diffusion. Prasad (Prasad et al., 2007) studied radiation and mass transfer effects on two dimensional flow past an impulsively started infinite vertical plate. Kim (J. Kim Youn, 2000) has considered an unsteady MHD convective heat transfer past a semi-