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arXiv · 1808.01943

The new mode of instability in viscous high-speed boundary layer flows

Jie Ren·Youcheng Xi·Song Fu
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Abstract

The new mode of instability found by Tunney et al. is studied with viscous stability theory in this article. When the high-speed boundary layer is subject to certain values of favorable pressure gradient and wall heating, a new mode becomes unstable due to the appearance of the streamwise velocity overshoot ($U(y)>U_\infty$) in the base flow. The present study shows that under practical Reynolds numbers, the new mode can hardly co-exist with conventional first mode and Mack's second mode. Due to the requirement for additional wall heating, the new mode may only lead to laminar-turbulent transition under experimental (artificial) conditions.

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Jie Ren, Youcheng Xi, Song Fu. 2018-08-06. The new mode of instability in viscous high-speed boundary layer flows. https://arxiv.org/abs/1808.01943

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