Numerical investigation on the effect of vortex generator shapes on film cooling performance

Abstract

This paper presents a numerical investigation on the concept for enhancing film cooling performance by placing shaped vortex generators (VG) upstream of the film hole. Nine cases with different shapes of vortex generators are investigated, including the rectangular shape, triangular shape, parallelogram shape, and trapezoid shape. The film cooling performance is evaluated at the density of 0.97 with the blowing ratios ranging from 0.5 to 1.5. Results obtained show that the film cooling performance is greatly improved by the upstream VG. The twisted flow rotates in the opposite direction of kidney vortices, attenuating its effect. Furthermore, the case with rectangular VG shows the most uniform coolant layer in the spanwise direction and the highest averaged adiabatic cooling effectiveness while the total pressure loss increases a bit as a penalty.