Numerical Analysis of Film Cooling of Gas Turbine Blades using Shaped Holes

Film cooling of gas turbine blades is essential as increasing the combustor exit temperature and gas turbine inlet temperature improves the performance and efficiency of gas turbine. The focus of this numerical investigation is to investigate the film cooling performance of the laidback fan shaped holes. The study is carried out at different blowing ratios namely, M = 0.60, 1.25 and 1.50. All the comparison is made with the baseline cylindrical hole. Jet lift-off is found to be suppressed in the laidback hole in comparison with cylindrical hole. This suppression of jet lift-off by the laidback hole helps in ensuring the coolant to the closer to the bottom plate of the gas turbine blade thereby reducing the temperature observed on the gas turbine blade. This trend is observed to be increasing with blowing ratios. Moreover, the coolant spread is also found to be better in laidback fan shaped hole in comparisons with baseline cylindrical hole. Based on the temperature distributions patterns observed on the gas turbine blade, it can be concluded that laidback fan shaped hole provides a better lateral spreading of the ejected coolant and improved film cooling. © 2021 MechAero Foundation for Technical Research and Education Excellence .