FILM COOLING COMPARISON OF FULL-SCALE TURBINE VANES USING THE PRESSURE SENSITIVE PAINT TECHNIQUE

Abstract

This work is an experimental study of film cooling effectiveness on two real scale turbine vanes in a 3-vane annular cascade. The cascade is connected to a high flow steady compressor to provide the mainstream flow. The inlet velocity is maintained at 35 m/s at the center line of the annular cascade. Two heavily cooled, real scale turbine vanes are tested with cooling holes on the pressure and suction surfaces. Vane 1 has 645 cooling holes distributed around the vane. Vane 2 has an additional two row of holes at the near leading edge SS of the vane. The MFR is varied from 3.12% to 4.82%. Increasing the MFR increases the film effectiveness. The introduction of additional rows of cooling holes resulted in re-distribution of coolant from the pressure surface to the suction surface. This study provides designers with more insight into how to place rows of cooling holes to have improved effectiveness.