TY - JOUR
T1 - Effect of porous wall on Mach 6 boundary-layer transition over a flat plate
AU - Hong, Zheng
AU - Ye, Zhengyin
AU - Ye, Kun
N1 - Publisher Copyright:
© 2022 IAA
PY - 2022/11
Y1 - 2022/11
N2 - Stabilization of the Mack second mode is of great importance to control hypersonic boundary-layer transition, and the porous wall is one of the promising passive techniques. In this paper, the transition onset of a two-dimensional Mach 6 boundary layer over a flat plate with porous coating is predicted by the eN method based on the linear stability theory. The results show that the second mode instability over the smooth wall can be significantly stabilized by the porous coating. As a price, the other instabilities, mostly the lower-frequency first mode instability, are destabilized, which is more prominent over a hotter wall. Consequently, the transition onset over the porous wall is not always delayed obviously compared to the smooth wall, and even a premature transition is obtained for some porous walls, especially for a hot wall. To achieve an effective delay of transition onset over a hot wall, a sectionalized strategy is proposed in this paper. By partially using the porous wall at downstream location, the destabilization of first mode instability is relieved while the significant stabilization of second mode instability is retained for the most unstable wave, and thus the transition onset is delayed more effectively over a hot wall.
AB - Stabilization of the Mack second mode is of great importance to control hypersonic boundary-layer transition, and the porous wall is one of the promising passive techniques. In this paper, the transition onset of a two-dimensional Mach 6 boundary layer over a flat plate with porous coating is predicted by the eN method based on the linear stability theory. The results show that the second mode instability over the smooth wall can be significantly stabilized by the porous coating. As a price, the other instabilities, mostly the lower-frequency first mode instability, are destabilized, which is more prominent over a hotter wall. Consequently, the transition onset over the porous wall is not always delayed obviously compared to the smooth wall, and even a premature transition is obtained for some porous walls, especially for a hot wall. To achieve an effective delay of transition onset over a hot wall, a sectionalized strategy is proposed in this paper. By partially using the porous wall at downstream location, the destabilization of first mode instability is relieved while the significant stabilization of second mode instability is retained for the most unstable wave, and thus the transition onset is delayed more effectively over a hot wall.
KW - Hypersonic boundary layer
KW - Porous wall
KW - Second mode instability
KW - Transition delay
UR - http://www.scopus.com/inward/record.url?scp=85136574065&partnerID=8YFLogxK
U2 - 10.1016/j.actaastro.2022.07.031
DO - 10.1016/j.actaastro.2022.07.031
M3 - 文章
AN - SCOPUS:85136574065
SN - 0094-5765
VL - 200
SP - 226
EP - 241
JO - Acta Astronautica
JF - Acta Astronautica
ER -