%0 Journal Article
%T MHD Stagnation-Point Flow of Casson Fluid and Heat Transfer over a Stretching Sheet with Thermal Radiation
%A Krishnendu Bhattacharyya
%J Journal of Thermodynamics
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/169674
%X The two-dimensional magnetohydrodynamic (MHD) stagnation-point flow of electrically conducting non-Newtonian Casson fluid and heat transfer towards a stretching sheet have been considered. The effect of thermal radiation is also investigated. Implementing similarity transformations, the governing momentum, and energy equations are transformed to self-similar nonlinear ODEs and numerical computations are performed to solve those. The investigation reveals many important aspects of flow and heat transfer. If velocity ratio parameter (B) and magnetic parameter (M) increase, then the velocity boundary layer thickness becomes thinner. On the other hand, for Casson fluid it is found that the velocity boundary layer thickness is larger compared to that of Newtonian fluid. The magnitude of wall skin-friction coefficient reduces with Casson parameter (¦Â). The velocity ratio parameter, Casson parameter, and magnetic parameter also have major effects on temperature distribution. The heat transfer rate is enhanced with increasing values of velocity ratio parameter. The rate of heat transfer is enhanced with increasing magnetic parameter M for B > 1 and it decreases with M for B < 1. Moreover, the presence of thermal radiation reduces temperature and thermal boundary layer thickness. 1. Introduction In fluid dynamics the effects of external magnetic field on magnetohydrodynamic (MHD) flow over a stretching sheet are very important due to its applications in many engineering problems, such as glass manufacturing, geophysics, paper production, and purification of crude oil. The flow due to stretching of a flat surface was first investigated by Crane [1]. Pavlov [2] studied the effect of external magnetic field on the MHD flow over a stretching sheet. Andersson [3] discussed the MHD flow of viscous fluid on a stretching sheet and Mukhopadhyay et al. [4] presented the MHD flow and heat transfer over a stretching sheet with variable fluid viscosity. On the other hand, Fang and Zhang [5] reported the exact solution of MHD flow due to a shrinking sheet with wall mass suction. Bhattacharyya and Layek [6] showed the behavior of solute distribution in MHD boundary layer flow past a stretching sheet. Furthermore, many vital properties of MHD flow over stretching sheet were explored in various articles [7¨C12] in the literature. Several important investigations on the flow due to stretching/shrinking sheet are available in the literature [13¨C16]. Chiam [17] investigated the stagnation-point flow towards a stretching sheet with the stretching velocity of the plate being equal to
%U http://www.hindawi.com/journals/jther/2013/169674/