Effect of a detached rib behind a backward-facing step on separated flow dynamics and heat transfer

Abstract

Here, we present the experimental results on the influence of a detached rib behind a backward-facing step on the flow dynamics and heat transfer. The height of a slot between the lower edge of the rib and the channel wall was varied in the range dh/H = 0.7–1.3, and the distance between the rib and the step was varied within t/H = 0.2–3.2. The rib height was constant and equal to 0.3H, where H is the step height. The fields of static pressures were measured behind the point of flow separation at the step edge. The study was performed in the range of Reynolds numbers 14,200-42,500. The two-dimensional fields of velocities and their fluctuations were measured using the PIV method. Heat transfer was studied in the regime of constant heat flux on the channel surface, where the step was located. Behaviors of the pressure and velocity profiles, as well as heat transfer with varying the detached rib location relative to the step are shown.