Use of Rib Turbulators to Enhance Postimpingement Heat Transfer for Curved Surface

Abstract

The present study aims to investigate the heat transfer and pressure loss characteristics for multiple rows of jets impinging on a curved surface in the presence of rib turbulators. The target plate contains a straight section downstream of the impingement section. The rib turbulators are added only over the straight section, in an attempt to enhance the heat transfer while minimizing the pressure loss. The jet plate configuration in this study has fixed jet hole diameters and hole spacing. For the curved plate, the radius of the target plate is 32 times the diameter of the impingement holes. Impingement array configuration was chosen such that validation and comparison can be made with the open literature. For all the configurations, crossflow air is drawn out in the streamwise direction. Average jet Reynolds numbers ranging from 55,000 to 125,000 were tested. Heat transfer characteristics are measured using steady-state temperature-sensitive paint (TSP) to obtain local heat transfer distribution. The experimental results are compared with computational fluid dynamics (CFD) simulations. CFD results show that CFD simulations predict the heat transfer distribution well in the postimpingement area with turbulators.