Heat transfer measurements to a gas turbine cooling passage with inclined ribs

Abstract

The local heat transfer coefficient distribution over all four walls of a large scale model of a gas turbine cooling passage have been measured in great detail. A new method of determining the heat transfer coefficient to the rib surface has been developed and the contribution of the rib, at 5% blockage, to the overall roughened heat transfer coefficient was found to be considerable. The vortex dominated flow field was interpreted from the detailed form of the measured local heat transfer contours. Computational Fluid Dynamics calculations support this model of the flow and yield friction factors which agree with measured values. Advances in the heat transfer measuring technique and data analysis procedure which confirm the accuracy of the transient method are described in full.