Reynolds-Stress Model Computations of the NASA Juncture Flow Experiment

Abstract

Numerical simulations of the NASA Juncture Flow Experiment are carried out, employing a Reynolds-stress model. A transformation of the length-scale determining variable is suggested for improving the numerical robustness of the model. Results obtained with different unstructured flow solvers show very good agreement, when using sufficiently fine grids. The influence of a recently developed length-scale correction and of prescribed transition is investigated. While the length-scale correction has only a minor effect, prescribing transition according to the experimental tripping position appears to be essential for predicting the suction peak on the wing near the junction with the fuselage. Moreover, accounting for transition consistently increases the predicted size of the separation bubble in the junction. Generally, fair agreement with the experimental data is achieved, where the scatter of predicted bubble sizes due to the variation of the model is of the order of the experimental uncertainty.