Performance examination of geometry-independent near-wall second-moment closures in simple and backstep flows

Predictions of the characteristics of velocity fields in two simple flows, including a plane-channel flow and a zero-pressure-gradient flat-plate boundary layer, and in a separated flow behind a backward-facing step, by means of three selective geometry-independent low-Reynolds-number Reynolds stress models developed recently are presented. Choice of these models is made as a result of the comprehensive review of existing ways to compute complex-geometry turbulent flows, and taking into account the consideration of accurate, efficient, and stable calculations. Performance of the models is examined through comparison with available data of direct numerical simulation and measurements. A modification to the model developed by So and Yuan (1999) is then proposed and is shown to be capable of yielding better performance.