Heat Release in Turbine Cooling II: Numerical Details of Secondary Combustion Surrounding Shaped Holes
Film cooling plays a critical role in providing effective thermal protection to components in modern gas turbine engines. Most of the previous studies on film cooling were conducted using either cylindrical or shaped coolant holes with nonreactive pure gases in the cross-stream flow. In this paper, the chemically reactive film cooling over a surface with shaped coolant hole is investigated by a Reynolds-averaged Navier–Stokes approach with a shear-stress transport k-!model to simulate the turbulentflow.To take into account the secondary combustion resulting from the unburned fuels in the crossflow, a two-step reaction scheme was used for the combustion of propane. An eddydissipation concept approach was used to account for the turbulence–chemistry interaction. The three-dimensional simulation was performed on an unstructured hybrid grid. The characteristics of reactive thermal flows, jet– crossflow interactions, species transport, and fuel consumption were investigated at different equivalence ratios and blowing ratios. Numerical results provide insight into where reactions take place and how fuel is consumed.