FLOW AND HEAT TRANSFER CHARACTERISTICES IN A 3D CHANNEL WITH RIB TURBULATORS

Three-dimensional numerical predictions of the flow and heat transfer are presented for a channel with two angled ribs. The 20 deg ribs in respect to the main flow are attached on the bottom of channel wall as vortex generators to enhance heat transfer. The Prandtl number is 0.71 and the Reynolds number based on the inflow velocity and height of channel is 200. In the present study, the 3D-unsteady DNS simulation was performed using very fine resolution with more than one million grid points. Time-dependent simulations show that the flow and heat transfer characteristics become steady for the Reynolds number of this work. The structures of heat transfer and flow are studied by using velocity and vorticity components, temperature and Nusselt number. This study shows that the heat transfer is enhanced due to the generation of the Longitudinal and the horseshoe vortices.

کلیدواژه ها:

angled ribs-heat transfer enhancement-numerical study-DNS ، channel flow