Numerical simulation of cooling effectiveness with injection of double-outlet hole

In order to optimize the structure of the film cooling,the film cooling performance of a novel hole with double-outlet was investigated by numerical simulation.The Navier-Stokes equation was solved by Fluent.The realizable k-ε model and enhanced function were used.The numerical effectiveness of the cylindrical hole agrees well with the experimental data.The result of the double-outlet hole injection shows that the lateral spreading of the film is improved as compared to the injection of the cylindrical hole.At the blowing ratio of 0.5,the vortices at the trunk hole outlet are reduced by the injection of the branch hole.At the blowing ratio of 1.0 and 2.0,the vortices at the trunk hole outlet are eliminated by the injection of the branch hole.The optimal blowing ratio is found at blowing ratio of 1.0.The double-outlet hole improves the cooling effectiveness significantly while requiring for easily machinable round hole as compared to expanded hole.