摘要

In the present paper the effect of roughness on the film cooling has been investigated numerically using Large Eddy Simulation (LES). A range of roughness parameters relative to the momentum thickness of the crossflow boundary layer have been studied. A roughness element model is used for representing the micro-roughness over the film-cooled surfaces. Results for different roughness parameters are analyzed and compared with the baseline smooth case. Beyond 2 hole diameters of coolant injection, roughness is shown to reduce cooling effectiveness.