Turbulent wedge modeling in intermittency-based transition models at high Reynolds numbers

Kurzfassung

This article presents an approach to set turbulent wedges and transition trippings in local correlation-based intermittency transport transition models. Turbulent wedges are created by increasing the intermittency at the wedge apex or the tripping location. Downstream, no further interference with the transition model is required. The method is demonstrated for the NASA CRM-NLF configuration in a transonic high Reynolds number flow. Prior research on this and other configurations has already shown the important influence of turbulent contamination and boundary layer trippings on the overall aerodynamics. Turbulent wedges and a tripping along a polyline are successfully created for two different intermittency transport models. It is observed that the wedge angles are too large compared to the experimental data. Grid spacing, initial disturbance size, and scaling of the diffusion term only have a minor effect on the wedge angles. This indicates the need to improve the overall transport behavior of the intermittency transport equation for three-dimensional flows. Reynolds number effects are investigated to demonstrate limits of the approach as the transition model gets less sensitive to local disturbances for decreasing Reynolds numbers. In addition to steady transonic flows, the method is also shown for an unsteady transonic flow.