Computation And Analysis Of Film Cooling Based On Jet Model For Turbines

High pressure turbine is treated as the core component of the aero-engine.The requirement of better performance for the high pressure turbine arises with the attractive tendency of higher thrust to weight ratio and lower fuel consuming for an advanced aero-engine,which ultimately results in severe operating conditions with increasing inlet temperature.Furthermore,the safety of gas turbine requires advanced cooling system,where the film cooling plays a quite important role.Therefore,predicting the film cooling flow field in a turbine accurately is of great importance for the reasonable design of the cooling system.The main objective of present work is to develop a film cooling ejection model,which can be embedded in an in-house CFD software NUAA-Turbo.This model will contribute to predicting the flow field in a turbine with saving computer and time resources.Furthermore,the Immersed Boundary Method was introduced in order to combine the ejection model with the computational mesh.Then the experimental validation of the film cooling ejection model was presented briefly.Meanwhile,this model was verified for a simple flat plate with good agreement between computational and experimental results.The effects of the streamwise ejection angle and the momentum flux ratio on the film cooling efficiency were further analyzed.Finally,numerical simulations on the MT1 high pressure turbine vane with film cooling were performed for engineering application.The developed film cooling ejection model was further validated with reasonable agreements between the prediction and experimental data.Meanwhile,the aero-thermal performance of the film cooling flow field was analyzed,and the mixing process between the coolant ejection and the main flow,and the corresponding effects on the downstream cooling efficiency were investigated.