Application of turbulence models for aerodynamic and propulsion flowfields

An evaluation of two algebraic models, two one-equation models, and six two-equation turbulence models is made for compressible flows encountered in current aircraft applications. A zonal, upwind, implicit, factored algorithm is used to solve both the mean flow equations and the turbulence model equations for three-dimensional, compressible turbulent flow. Calculations are presented for two transonic supercritical airfoils, a single-slot two-dimensional ejector nozzle, and a highly offset three-dimensional diffuser. The influence of two modifications to the production of turbulent kinetic energy for the low Reynolds number k-e models is evaluated, a vorticity-based strain rate and a production limiter. The production limiter greatly improves the accuracy of the predicted flowfields. Comparisons of the results of the various turbulence models are made with experimental measurements. Significant differences are observed in the model predictions when applied to the same problem using the same computational mesh and mean flow salver. The algebraic models are unable to capture the physics of these complex flowfields, particularly for the internal flow calculations. Each one-equation and two-equation model has specific strengths and weaknesses and the performance of each model is assessed.