Wall-Resolved Large-Eddy Simulation of Smooth-Body Separated Flow

Abstract

Wall-resolved large-eddy simulations were carried out for flow over a rearward-facing ramp configuration, which is representative of surfaces generating smooth-body separation. The geometry and flow conditions were motivated by an experimental investigation, which was conducted in order to provide data for validating numerical modelling. Because the experimental Reynolds number is challenging, even for approximate techniques, the present computations were initiated in order to provide benchmark results for a comparison of numerical methods. Solutions to the unsteady three-dimensional compressible Navier-Stokes equations were obtained utilising a high-fidelity computational scheme and an implicit time-marching approach. Grid resolution studies were performed to assure numerical accuracy. A number of metrics are indicated that attest to quality of the solutions. Features of the flowfields are elucidated, and comparisons are made between results at two different Reynolds numbers. A description of boundary-layer parameters and development of turbulence along the ramp surface are also provided.