Convective heat transfer characteristics of twin-web turbine disk with pin fins in the inner cavity

In order to enhance the convective heat transfer effect of high pressure turbine disk, a novel twin-web turbine disk with pin fins in the inner cavity is developed. The convective heat transfer characteristics of the traditional TWD and the TWD with pin fins are analyzed by numerical method verified by a hollow disk model. The results show that there is a circular flow in the inner cavity which impacts the back and front web to enhance the local convective heat transfer coefficient. The Nusselt number of the back web is remarkably higher than that of the front web, and the temperature of the back web is visibly lower than that of the front web. The pin fins in the inner cavity compress the circular flow and make it move downward, so that the Nusselt number in the region below the pin fins is improved; meanwhile, local convective heat transfer coefficient and the area of heat exchange have both increased to improve the convective heat transfer effect. The convective heat transfer characteristics of the developed TWD with six Reynolds numbers are analyzed, the average Nusselt number of the inner cavity surface with pin fins are as much as about 10% larger than that of the traditional TWD, the flow resistance coefficients of the inner cavity of TWD with pin fins is about 11% higher than that of the traditional TWD.