Adiabatic effectiveness and heat transfer coefficient on a film-cooled rotating blade

A three dimensional Navier-Stokes code has been used to compute the adiabatic effectiveness and heat transfer coefficient on a rotatingfilm-cooled turbine blade. The blade chosen is the United Technologies Research Center (UTRC) rotor with five film-cooling rows containing 83 holes, including three rows on the shower head with 49 holes, covering about 86% of the blade span. The mainstream is akin to that under real engine conditions with stagnation temperature 1900 K and stagnation pressure 3 MPa. The blade speed is taken to be 5200 rpm. The adiabatic effectiveness is higher for a rotating blade as compared to that for a stationary blade. Also, the direction of coolant injection from the shower-head holes considerably affects the effectiveness and heat transfer coefficient values on both the pressure and suction surfaces. In all cases the heat transfer coefficient and adiabatic effectiveness me highly three-dimensional in the vicinity of holes but tend to become two-dimensional far downstream.