Computational investigations of flow and heat transfer on an effused concave surface with a single row of impinging jets for different exit configurations

A computational study is reported on flow and heat transfer from a single row of circular air jets impinging on a concave surface with either one or two rows of effusion holes or without effusion holes. The effects of arrangement of jet orifices and effusion holes, spent air exit closure configurations, H/D ratio and jet Reynolds number are investigated. The pressure distribution is higher for the configuration with the air exit only through effusion holes. At higher Reynolds number, three peaks in local Nusselt number are identified and explained. Among the cases tested, the configuration with a single row of inline effusion holes shows the least heat transfer and there is a significant local enhancement in heat transfer along the stagnation line for a single row of staggered effusion holes. However, the effect of arrangement is negligible for two rows of effusion holes. Among the configurations tested the case of one edge open exit configuration with a single row of staggered effusion holes (Case-C1s) shows higher heat transfer among others.