Automatic Transition Prediction and Application to High-Lift Multi-Element Configurations

Abstract

A Reynolds-averaged Navier-Stokes (RANS) solver, a laminar boundary layer code and an e(N)-database method for transition prediction were coupled in order to perform RANS computations of two-dimensional high-lift multi-element systems with automatic laminar-turbulent transition prediction and transitional flow regions. It will be shown, that the coupled system represents a RANS-based CFD tool that provides accurated values of the transition locations during the ongoing RANS computation automatically and fast without the need for the intervention by the code user. Thus, RANS computations of two-dimensional high-lift multi-element configurations with transition can be carried out without a priori knowledge of the transition characteristics of the specific flow problem. The coupling structure and the underlying algorithm of the transition prediction procedure as well as the physical modelling of transitional flow regions and their generation in the RANS computational grid are described. The testing of the transition prediction procedure is described and documented. The computational results are compared to experimental data.