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arXiv · 1501.06628

Transition in Hypersonic Boundary Layers: Role of Dilatational Waves

Chuanhong Zhang·Yiding Zhu·Huijing Yuan·Jiezhi Wu·Shiyi Chen·Cunbiao Lee·Mohamed Gad-el-Hak
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Abstract

Transition and turbulence production in a hypersonic boundary layer is investigated in a Mach 6 quiet wind tunnel using Rayleigh-scattering visualization, fast-response pressure measurements, and particle image velocimetry. It is found that the second instability acoustic mode is the key modulator of the transition process. The second mode experiences a rapid growth and a very fast annihilation due to the effect of bulk viscosity. The second mode interacts strongly with the first vorticity mode to directly promote a fast growth of the latter and leads to immediate transition to turbulence.

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Chuanhong Zhang, Yiding Zhu, Huijing Yuan, Jiezhi Wu, Shiyi Chen, Cunbiao Lee, Mohamed Gad-el-Hak. 2015-02-01. Transition in Hypersonic Boundary Layers: Role of Dilatational Waves. https://arxiv.org/abs/1501.06628

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