Numerical investigation on the effect of sister holes on film cooling performance with Barchan-dune shaped shells

The film cooling is the traditional and efficient technique that is used to adopt the turbine cooling process, a new configuration that combines sister holes with Barchan-dune shaped shells (SH-BDS) is used in this study to improve the film cooling effectiveness laterally and at spanwise direction. The investigations are performed for high blowing ratios, M = 1 and 1.5. Three-dimensional Reynolds Averaged Navier-Stokes (RANS) equations with the RNG k-epsilon model are solved to simulate and analysis the thermal behaviour of this new configuration. The validation shows good agreement and almost all flow structures are well reproduced. It is found that the new configuration provides a significant change in the film cooling effectiveness results. Moreover, the counter-rotating vortex pairs structure (CRV) is nearly vanished. From this contribution, it is well demonstrated that this new technique (SH-BDS) has a great influence on the cooling process of the turbine and hence on its effective functioning.