Numerical study on film cooling characteristics of c3x vane with wave-trench hole

To get wider laterally coverage of the cooling jet, the single-wave trench and double-wave trench were further studied on the vane. The film cooling characteristics of different film cooling structures were numerically studied using Reynolds Averaged Navier Stokes (RANS) equations. The SST turbulence model with γ-θ transition model was applied for the present simulation. The film cooling effectiveness and heat transfer coefficient of different film cooling structures were investigated, and the distribution of temperature field and flow field were analyzed. Four different blowing ratios (M) from 0.5 to 2.0 were studied. The results show that compared with the transverse trench structure, the span-wise averaged film cooling effectiveness of the double-wave trench increases 0.1-0.35. The single-wave trench and double-wave trench film cooling structures significantly improve the uniformity of the jet and increase the film cooling effectiveness. The span-wise averaged film cooling effectiveness of the double-wave trench is higher than that of the single-wave trench at high blowing ratio conditions. The anti-counter-rotating vortices which can press the cooling jet on near-wall are formed at the downstream single-wave trench and double-wave trench. Both of the double-wave trench and the single-wave trench structure can effectively improve the film cooling effectiveness of the vane in the case of a little increase in the heat transfer coefficient compared to the cylindrical hole. The guidance action of the double-wave trench is more reasonable, therefore the film cooling characteristics is better than that of the single-wave trench.