It is observed that the normal k-ε turbulence model,which is very popular in computational fluid dynamics,is inapplicable to predicting the film cooling recovery region flow successfully.The reason might be the fact that the profiles of flow parameters are significantly different from those in normal boundary layer due to the blowing and the distance needed for flow returning to the normal boundary layer is too large.A new turbulence model based on Lam-Bremhorst low Reynolds number k-ε turbulence model has been proposed for prediction of the film cooling recovery region.It was found that the constant c μ and c 1 in the original model should be modified to be functions of coordinates x and y,and the low Reynolds number functions f μ,f 1 and f 2 should be varied with x and y too.The modified expressions feature that they should be approaching to nonblowing boundary layer when the distance from initial section becomes large enough.Three numerical examples demonstrate the advantages of this new model over the original one for the blowing ratio ranging from 0 4 to 1 0.
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