Large eddy simulation of film cooling under rotating condition

Large eddy simulation was used to predict flow and heat transfer of film cooling on a flat plate perforated by 35° streamwise inclined cylindrical hole of 4 mm under stationary and rotation conditions. The predicted non-dimensional velocity profiles compared well with available experimental data in stationary case, justifying present simulations. But the discrepancy of temperature predicted by present work and that in reference numerical work was obvious. After introducing system rotation at the same blowing ratio and Reynolds number, vorticity distributions showed increasing distinctness along with the increased angular velocity. And the trajectory of shear layer between mainflow and coolant deviated towards spanwise under rotation condition, leading to the asymmetry of the counter rotating vortex pair after coolant injection. Furthermore, the dynamics of coherent structures detected in three cases also demonstrate the rotation effect, which significantly influences the mixing of mainflow and coolant and the consequential heat transfer.