New model for film cooling effectiveness computation on blade surface in a turbine cascade

Predictions of span-wise averaged effectiveness were made with a two-dimensional boundary layer code using the low Reynolds number k-ε two-equation turbulent model. A new injection model, which was incorporated in the code, for describing the discrete-hole injection process was made. The code can be used to calculate the film cooling effectiveness on the turbine blade surface. The computation results give out four typical regions on blade surface. The correlations between empirical parameters and blowing ratios are developed at different regions independently and used to compute the cooling effectiveness on the downstream of single row gas holes on blade surface. The calculated results completely agree with test data.