A detailed study of effects of row trenched holes at the combustor exit on film cooling effectiveness

Abstract

The current research was performed in order to analyze the effects of cylindrical and row trench cooling holes with the alignment angle of 90 degrees on the film-cooling effectiveness near the combustor endwall surface at the blowing ratio of BR=3.18. The three-dimensional representation of a Pratt and Whitney gas turbine engine was simulated and analyzed with the commercial finite volume package, FLUENT 6.2.26. in order to find the most effective row trenched cooling holes. The analysis was done with Reynolds averaged Navier-Stokes turbulence model (RANS) on internal cooling passages. This combustor simulator was combined with the interaction of two rows of dilution jets, which were staggered in the stream-wise direction and aligned in the spanwise direction. In comparison with the baseline case of cooling holes, using a row trenched hole near the endwall surface increased the film-cooling effectiveness by 44% in average.