Effect of plenum feed configurations on the cooling effectiveness in the hybrid cooling configuration

The present study concentrates on the computational investigation of a new cooling configuration of a double-layer cavity in the middle section of modern turbine blade. A three-dimensional Navier-Stokes code with standard k-ε turbulence model as well as with wall functions was used to compute the flow and heat transfer characteristics for a combined impingement and film cooling configuration. The blowing ratios are from 0.6 to 2.0, and the Reynolds number based on the inlet velocity of the cooling air and hole diameter varied from 2000 to 5000. Additionally, the effect of the plenum feed configurations (co-flow and counter flow) on hybrid cooling effectiveness were discussed. Numerical results reveal that a larger hybrid cooling effectiveness is reached with higher Reynolds number and blowing ratio. And the plenum feed configurations are found to affect hybrid cooling effectiveness significantly. The maximum of hybrid cooling effectiveness is achieved with the configuration of counter flow.