Curvature-Sensitive Transition Model Application to Flow Around a Smooth Circular Cylinder

Abstract

Transition modeling in complex flow situations including adverse pressure gradient, streamline curvature, and massive flow separation represents one of the key challenges in computational fluid dynamics that greatly affects the flow characteristics in many thermal and fluid sciences applications. Here, we report a comparative study that helps investigate the capability of the curvature-sensitive kT−kL−ω−v2 transition model against the original kT−kL−ω algorithm in predicting the flow behavior surrounding a smooth circular cylinder subjected to Reynolds numbers in the range from 3.9×103 to 3.6×106. A C-program that fully accounts for the model's four transport equations is particularly developed and coupled with the transient solver of ansysfluent. The present simulation enables accurate prediction of the distributions of skin-friction and pressure coefficients along with careful specification of the corresponding drag coefficients and angles of separation and transition. The simulation reveals insignificant variations in the bulk flow behaviors using either model in both sub- and critical flow regimes while a remarkable improvement in the supercritical drag result is achieved using the curvature-sensitive model.