Simulation calculations were carried out using 3D-CFD code:FLUENT [6]. Governing equations considered are the continuity,momentum, and energy equations. Turbulence was taken into account by the ReNormalization Group (RNG)
k–e model and wall function. All equations were solved using second-order upwind discretization for convection. The semi implicit method pressure linked equation (SIMPLE) algorithm was used to resolve coupling of the velocity and pressure.