Large Eddy Simulation of a Controlled-Diffusion Cascade Blade at Varying Flow Inlet Angles

A Controlled Diffusion cascade stator blade has been studied numerically using Large Eddy Simulation (LES). The aim of the study is to assess the performance of Large Eddy Simulation in predicting flow features on a highly-loaded blade, including leading-edge separation, transition and turbulent reattachment, particularly at off-design conditions. The need for LES to be performed on high resolution grids is highlighted by preliminary simulations on a mesh typically used in Reynolds-Averaged approaches. On a fine grid, the unsteady flow features captured by time-dependent simulation yield an improvement in surface pressure distributions and boundary layer profiles, although some weaknesses are apparent in the prediction of pressure-side boundary layer properties and wake profiles. The computed loss coefficients show potential for LES to be used to obtain loss-loop data over a wide range of incidence angles.© 2009 ASME