ABSTRACT

Improvements in the performance and efficiency of modern gas turbine engines have been made by increasing the compression ratios and maximum temperatures at which they operate. One of the problems of great importance to the gas turbine designer is the heat transfer resulting from the flow of air circulating in the various chambers or cavities formed by the turbine disk assembly of the rotor. In order to gain a better understanding of the flow structures a research program using flow visualization and laser Doppler anemometry was undertaken. The approach was to construct a simplified experimental rig that incorporated the essential features of the more complex coolant-flow arrangements to be found in a gas turbine. Tests conducted in a heated cavity suggest that instabilities in the axial jet play a significant role in increasing the heat transfer from the hot disk to the air in the cavity.