Computation of Leading-Edge Film Cooling With Injection Through Rows of Compound-Angle Holes

Abstract

Computations were performed to investigate the three-dimensional flow and heat transfer about a semi-cylindrical leading edge with a flat afterbody that is cooled by film-cooling jets, injected through three staggered rows of compound-angle holes with one row along the stagnation line and two rows along ±25°. Results are presented for the surface adiabatic effectiveness, temperature distribution, velocity vector field, turbulent kinetic energy, and surface pressure. These results show the interactions between the mainstream hot gas and the cooling jets, and how those interactions affect surface adiabatic effectiveness. The computed results were compared with experimental data generated under a blind test, and reasonably good agreements were obtained. This computational study is based on the ensemble-averaged conservation equations of mass, momentum (compressible Navier-Stokes), and energy closed by a low Reynolds number k-ω turbulence model. Solutions were generated by a cell-centered finite-volume method that uses second-order accurate flux-difference splitting of Roe on a multiblock structured grid system. In the computations, the flow is resolved not just in the region about the leading edge, but also inside the film-cooling holes and in the plenum where the cooling flow emerges.