Zihui Hao

TL;DR: In this paper, an improved γ-Reθt model was developed to predict the heat transfer of hypersonic boundary layer transition in a flat plate and X-51A forebody with different Reynolds numbers and wind tunnel noise levels.

TL;DR: In this paper, a grid-reorder method is developed to obtain the boundary layer parameters, which is suitable for parallel computing in this paper, and the method has been coupled to three transition prediction methods, the γ-Reθ model, the k-ω-γ mo...

Abstract: Boundary layer transition is important for thermal protection and drag reduction in the design of hypersonic vehicles. A three-equation k-ω-γ model is applied in predicting a hypersonic flat plate transition with different Reynolds numbers. The transition onset advances with Reynolds number and the boundary thickness becomes thinner in the laminar zone before transition onset. The Mack modes dominate the hypersonic boundary layer transition. The first mode is viscous instability and the second mode is inviscid instability. The second mode distributes near the wall in the region Ma rel >1 and the value is larger than the first mode time scale in the laminar zone. The first and second mode time scale, non-turbulence viscosity and equivalent fluctuation kinetic both increase with Reynolds number increasing.

TL;DR: In this paper, a laminar kinetic energy transition model appropriate for hypersonic flow heat transfer is proposed, and three rectifications are made to make it possess the ability to predict hypersonics flow transition.