Heat transfer behind the backward-facing step under the influence of longitudinal pressure gradient

Abstract

Results of an experimental and numerical study of the flow structure and turbulent heat transfer in a rectangular channel with longitudinal pressure gradient behind the backward-facing step. With the channel expansion the angle of rotation of the upper wall is 1.43; 2.86 and 4°, and with the channel convergence the rotation angle is 3; 5.7 and 7.6°. Experiments are carried out at Reynolds numbers, calculated on the step height and velocity in front of the backward-facing step, ReH = 4 000; 8 000; 12 000. It was determined, with the increase of pressure gradient the maximum value of Nusselt number increases for the converging channel and decreases for the expanding channel.