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arXiv · 1607.00195

Aerodynamic Heating in Hypersonic Boundary Layers:\ Role of Dilatational Waves

Yiding Zhu·Xi Chen·Jiezhi Wu·Shiyi Chen·Cunbiao Lee·Mohamed Gad-el-Hak
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Abstract

The evolution of multi-mode instabilities in a hypersonic boundary layer and their effects on aerodynamic heating are investigated. Experiments are conducted in a Mach 6 wind tunnel using Rayleigh-scattering flow visualization, fast-response pressure sensors, fluorescent temperature-sensitive paint (TSP), and particle image velocimetry (PIV). Calculations are also performed based on both parabolized stability equations (PSE) and direct numerical simulations (DNS). It is found that second-mode dilatational waves, accompanied by high-frequency alternating fluid compression and expansion, produce intense aerodynamic heating in a small region that rapidly heats the fluid passing through it. As a result, the surface temperature rapidly increases and results in an overshoot over the nominal transitional value. When the dilatation waves decay downstream, the surface temperature decreases gradually until transition is completed. A theoretical analysis is provided to interpret the temperature distribution affected by the aerodynamic heating.

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Yiding Zhu, Xi Chen, Jiezhi Wu, Shiyi Chen, Cunbiao Lee, Mohamed Gad-el-Hak. 2016-07-01. Aerodynamic Heating in Hypersonic Boundary Layers:\ Role of Dilatational Waves. https://arxiv.org/abs/1607.00195

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