Numerical Simulation of Twin Impinging Jets in a Cross-flow

摘要

When a vertical/short take-off and landing (VSTOL) aircraft is operated near the ground, a very complex flow field is created. This flow field can be represented by the configuration of twin impinging jets along the spanwise direction in a cross-flow. This paper presents a numerical study of this flow using the Reynolds Averaged Navier-Stokes (RANS) approach with a Reynolds Stress Model (RSM). The use of an RSM potentially offers a compromise between the computational efficiency of a k-ε model and the accuracy of a Large Eddy Simulation (LES). The current numerical results are validated against experimental data and the mean velocity profiles are reasonably well predicted by both the A-e model and the RSM with slightly better prediction by the RSM. However, the Reynolds stress prediction by the RSM is poor compared with the experimental data while LES does a much better job in this respect, indicating that to capture the unsteady flow features accurately LES is needed.