Film cooling on a convex surface with zero pressure gradient flow

The adiabatic film cooling effectiveness and heat transfer increase due to film injection was investigated on a convex surface at zero pressure gradient flow. Film cooling results were obtained using thermochromic liquid crystals to measure the local wall temperature distribution. Five different injection configurations, three with cylindrical and two with shaped holes were examined. Coolant injection with cylindrical holes indicates decreased film cooling effectiveness and increased heat transfer at moderate and high blowing rates. Significant higher film cooling effectiveness values and lower heat transfer increase due to film injection were achieved by shaped hole injection compared to cylindrical hole injection.