TY - JOUR T1 - The New Mode of Instability in Viscous High-Speed Boundary Layer Flows AU - Ren , Jie AU - Xi , Youcheng AU - Fu , Song JO - Advances in Applied Mathematics and Mechanics VL - 5 SP - 1057 EP - 1068 PY - 2018 DA - 2018/07 SN - 10 DO - http://doi.org/10.4208/aamm.OA-2017-0298 UR - https://global-sci.org/intro/article_detail/aamm/12587.html KW - Boundary layer stability, compressible boundary layers, high-speed flow. AB -

The new mode of instability found by Tunney et al. [24] 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 ($U(y) > U_∞$) in the base flow. The present study shows that under practical Reynolds numbers, the new mode can hardly co-exist with the 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.