International Scholarly Research Network ISRN Thermodynamics Volume 2012, Article ID 217278, 7 pages doi:10.5402/2012/217278 Research Article Conjugate Effects of Radiation Flux on Double Diffusive MHD Free Convection Flow of a Nanofluid over a Power Law Stretching Sheet Muhammad Imran Anwar, 1 Sharidan Shafie, 1 Ilyas Khan, 1 and Mohd Zuki Salleh 2 1 Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia (UTM), Johor, 81310 Skudai, Malaysia 2 Faculty of Industrial Science and Technology, University Malaysia Pahang (UMP), Pahang, 26300 Kuantan, Malaysia Correspondence should be addressed to Sharidan Shafie, ridafie@yahoo.com Received 17 September 2012; Accepted 30 October 2012 Academic Editors: A. Ghoufi, R. D. Simitev, and Z. Xu Copyright © 2012 Muhammad Imran Anwar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This study theoretically investigates the conjugate effects of radiation flux and magnetohydrodynamic (MHD) on free convection boundary layer flow of a nanofluid over a nonlinear stretching sheet. It is assumed that the magnetic Reynolds number is small enough and the sheet is stretched with a power law velocity under the effects of the magnetic field, the buoyancy parameter, and the solutal buoyancy parameter. The model used for the nanofluid incorporates the effects of Rosseland approximation, Brownian motion, and thermophoresis parameters. By using appropriate similarity transformations, the governing nonlinear partial differential equations are transformed into dimensionless form and numerically solved using an implicit finite difference scheme known as the Keller-box method. It is found that the variations of magnetic field, buoyancy parameter, solutal buoyancy parameter, and the power law velocity parameter have strong influence on the motion. 1. Introduction Heat and mass transfer (double-diffusion) phenomenon on free convection is driven by two density gradients which have different rates of diffusion and currently is an important fluid dynamics topic. A common example of double diffusive convection appears in oceanography, where heat and salt concentrations exist with different gradients and diffuse at differing rates. Double diffusive convection is also important in understanding the evolution of a number of systems that have multiple causes for density variations. These include convection in the earth’s oceans, in magma chambers, and in the sun where heat and helium diffuse at differing rates [1]. Double diffusive convection flows for Newtonian and non-Newtonian fluids are extensively studied. However, for nanofluids such studies are scarce due to their complicated nature [2, 3]. Moreover, recent developments in the field of fluid dynamics and nanotechnology confirm that nanofluids are industrially more important than other available fluids [4]. There are numerous biomedical applications that involve nanofluids such as magnetic cell separation, drug delivery, hyperthermia, and contrast enhancement in magnetic res- onance imaging [5]. Hence, this is the motivation for considering nanofluids in the present work. On the other hand, stretching sheet problems with double diffusion are important in extrusion process, glass fibber, paper production, hot rolling, wire drawing, elec- tronic chips, crystal growing, plastic manufactures, food processing, and movement of biological fluids [6]. Khan and Pop [7] investigated the laminar flow of a nanofluid on a stretching flat surface by incorporating the effects of Brownian motion, thermophoresis and reported to be the pioneer for this study of stretching sheet in nanofluid. Rana and Bhargava [8] discussed the flow and heat transfer of a nanofluid over a nonlinearly stretching sheet. Furthermore, the MHD flow of nanofluid over a power law stretching sheet plays an important role in various industrial applications including magnetic control of molten iron flow in the steel industry and liquid metal cooling in nuclear reactors [9]. In addition, when thermal radiation is considered, such studies have useful chemical processing applications [10, 11].