Effects of Important Parameters on the Transition from Forced to Mixed Convection Flow in a Square Cavity

Abstract

Combined free and forced convection in a square cavity filled with a viscous fluid characterized by a small Prandtl number is studied numerically. The left wall is moving with a constant velocity v and is maintained at a local cold temperature Tc, while the right wall is fixed and maintained at a local hot temperature Th (Tc <Th). The top and bottom walls of the cavity is assumed to be adiabatic. The governing Navier-Stokes, and energy equations along with appropriate boundary conditions are solved using the finite-volume method. The flow and temperature fields are presented by stream function and isotherms, respectively. The effects of important parameters such as Reynolds number, Prandtl number, and Grashof number on the transition from forced convection to mixed convection are investigated. Results indicate that increasing Reynolds number results to fluid acceleration and, thus, to flow transition. Results also show that Grashof and Prandtl's numbers influenced the conditions for the transition to the mixed convection regime.