Study of hypersonic boundary layer transition with different reynolds numbers

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 Marel >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.