Direct numerical simulation of the effects of upstream turbulence on flow over aircraft engine turbine blades

Two-dimensional numerical simulations of the flow over an aircraft turbine blade are reported, with a focus on the effects of Reynolds number and upstream turbulence. The numerical procedure is based on finite differences using structured grids in a generalized curvilinear coordinate system. Results from companion experiments carried out at the Texas A & M University have been used to validate the numerical calculations. The results show that upstream turbulence precipitates early transition and inhibits separation at the lower Reynolds numbers. It also enhances heat transfer, even at the low Reynolds numbers where transition has not occurred.