Abstract: The three-dimensional boundary layer is ubiquitous in hypersonic vehicles, and transition process is significantly affected by the crossflow instability, resulting in complex transition patterns. To improve the prediction ability of the transition model for hypersonic three-dimensional boundary layer, on the basis of γ-Re_θt transition model coupled with the SST turbulence model, a crossflow effect modification method based on local flow variables is proposed. The analysis, verification and application of the crossflow modification method are carried out on the elliptical cone. The numerical simulation results show significant crossflow features in the hypersonic boundary layer on the elliptical cone, and crossflow transition occurs in the middle of the model. It is demonstrated that, the crossflow Reynolds number criterion can effectively characterize the crossflow effect of the three-dimensional boundary layer, and the proposed crossflow modification method improves the prediction ability for crossflow transition. The transition patterns close to those of the wind tunnel experimental data and high-fidelity simulation are obtained by calibration of the crossflow modification parameters. The verification of wind tunnel test and flight test data indicates that, the proposed transition model crossflow modification method achieves good application effect on the transition prediction of hypersonic three-dimensional boundary layer.

Key words: hypersonic, elliptic cone, boundary layer, crossflow, transition modelhttp