Heat Transfer Evaluation on Turbine Vane With Corrugated Wall Impingement Structure Using Infrared Camera

Impingement cooling is an effective technique used to cool hot gas path parts, minimizing the amount of cooling air required, and thereby improving the performance of gas turbines. However, crossflow from spent air of upstream impingement jets disrupts downstream impingement jets resulting in decreased heat transfer performance. To reduce the influence of crossflow, prior investigators have proposed using a corrugated wall type impingement structure. Although fundamental tests of simplified corrugated wall impingement structures have been conducted in the past to confirm the basic cooling performance, it is desirable to verify the metal temperature distribution on an actual turbine vane cooled by a corrugated wall impingement structure. This study presents results from a turbine cascade test where pressure and suction side surface temperatures of an actual vane are measured using an infrared camera. Thermocouples mounted at different locations around the vane are used to correct the IR thermal image data. Based on these measurements, it was concluded that the corrugated wall impingement structure can achieve the target cooling effectiveness for both pressure side and suction side airfoil surfaces.