Measurements of Turbulent Mixed Convection Flow Over a Vertical Forward-Facing Step

Measurements of turbulent mixed convection boundary-layer air flow over a two-dimensional, vertical forward-facing step are presented. The upstream and downstream walls and the step itself were heated to a uniform and constant temperature. Air velocity and temperature distributions and their turbulent fluctuations are measured simultaneously by using a two-component laser-Doppler velocimeter (LDV) and a cold wire anemometer were used, respectively. The present study treats buoyancy-dominated mixed convection over a vertical forward-facing step and examines the effect of a small free stream velocity on turbulent natural convection. It was found that the reattachment length increases while the heat transfer rate from the downstream heated wall decreases as the small free stream velocity increases