## THERMAL SCIENCE

International Scientific Journal

### HYDROMAGNETIC FLOW AND HEAT TRANSFER OVER A BIDIRECTIONAL STRETCHING SURFACE IN A POROUS MEDIUM

**ABSTRACT**

In this study, we present a steady three-dimensional magnetohydrodynamic (MHD) flow and heat transfer characteristics of a viscous fluid due to a bidirectional stretching sheet in a porous medium. The heat transfer analysis has been carried out for two heating processes namely (i) the prescribed surface temperature (PST) and (ii) prescribed surface heat flux (PHF). In addition the heat transfer rate varies along the surface. The similarity solution of the governing boundary layer partial differential equations is developed by employing homotopy analysis method (HAM). The quantities of interest are velocity, temperature, skin-friction and wall heat flux. The results obtained are presented through graphs and tabular data. It is observed that both velocity and boundary layer thickness decreases by increasing the porosity and magnetic field. This shows that application of magnetic and porous medium cause a control on the boundary layer thickness. Moreover, the results are also compared with the existing values in the literature and found in excellent agreement.

**KEYWORDS**

PAPER SUBMITTED: 2010-09-26

PAPER REVISED: 2011-01-11

PAPER ACCEPTED: 2011-01-23

**THERMAL SCIENCE** YEAR

**2011**, VOLUME

**15**, ISSUE

**Supplement 2**, PAGES [S205 - S220]

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