Large Eddy Simulation of Film Cooling with Forward Expansion Hole: Comparative Study with LES and RANS Simulations

The forward expansion hole improves the film cooling effectiveness by reducing penetration of coolant jet into main flow compared to cylindrical holes. In addition, compound angles improve promoting lateral spreading on a wall. Evidently, combination angle and shaped further adiabatic effectiveness. with 15° expansion, 35° inclination angle, 0° 30° at 0.5 1.0 blowing ratios was numerically simulated Large Eddy Simulations (LES) Reynolds-averaged Navier–Stokes (RANS) simulations. results time-averaged effectiveness, temperature, velocity, root-mean-square (rms) values fluctuating velocity temperature profiles were experimental data Lee et al. (2002) verify how LES those RANS. For hole, fluctuations in contours are smaller than hole; thus, turbulence mixing intensity weaker lower respectively. This leads higher hole. By contrast, RANS do not exhibit or well. These discussed detail this paper.