Application of a local SGS model based on coherent structures to complex geometries

A coherent structure model (CSM) as a subgrid-scale (SGS) model [Kobayashi, H., 2005. The subgrid-scale models based on coherent structures for rotating homogeneous turbulence and turbulent channel flow. Phys. Fluids 17, 045104] is applied to complex geometries and is assessed its performance in large-eddy simulation. The CSM is one of the local SGS models, which mean herein "no averaging in homogeneous directions". Two types of simulation code are tested for the assessment: a structured-mesh code is used for a flow over a backward-facing step, and an unstructured-mesh one is used for a flow in an asymmetric plane diffuser and for staggered jets in crossflow. For all configurations, the CSM gives good predictions and is almost the same performance as the dynamic models. This local model is simple and stable, and suitable for complex geometries.