TURBULENT FORCED CONVECTION OVER A BACKWARD-FACING STEP WITH A PARTITION LOCATED ON THE UPPER WALL

Abstract

In the present study, a numerical investigation of forced turbulent convection at a backward-facing step with an adiabatic thin fin mounted on the upper wall is presented. The working fluid is air with the Prandtl number of 0.71. The governing equations are solved with a finite volume based commercial code. The turbulence effect is included using the k-epsilon model. The effects of various pertinent parameters, Reynolds number, fin length, and inclination angle on the fluid flow and heat transfer characteristics are numerically studied. It is observed that a fin alters the flow field and thermal characteristics and it can be used as a passive control device. When compared to the no-fin case, secondary peaks are observed in the local Nusselt number distributions with increasing Reynolds number due to the recirculating zones formed behind the fin which increase in size and extend towards the bottom wall with increasing fin length and Reynolds number. The maximum value in the Nusselt number increases with the installation of the fin for all cases considered and with the Reynolds number.