On the turbulence amplification in shock-wave/turbulent boundary layer interaction

Fang, Jian; Zheltovodov, Aleksandr A.; Yao, Yufeng; Moulinec, Charles; Emerson, David R.

Abstract

The mechanism of turbulence amplification in shock-wave/boundary layer interactions is reviewed, and a new turbulence amplification mechanism is proposed based on the analysis of data from direct numerical simulation of an oblique shock-wave/flat-plate boundary layer interaction at Mach 2.25. In the upstream part of the interaction zone, the amplification of turbulence is not essentially shear driven, but induced by the interaction of the deceleration of mean flow with streamwise velocity fluctuations, which causes a rapid increase of turbulence intensity in the near-wall region. In the downstream part of the interaction zone, the high turbulence intensity is mainly due to the free shear layer generated in the interaction zone. During the initial stage of turbulence amplification, the characteristics of wall turbulence, including compact velocity streaks, streamwise vortices and an anisotropic Reynolds stress, are well preserved. The mechanism proposed explains the high level of turbulence in the near-wall region observed in some experiments and numerical simulations.

• Journal Article Type: Article
• Acceptance Date: Apr 26, 2020
• Online Publication Date: Jun 18, 2020
• Publication Date: Aug 25, 2020
• Deposit Date: Jun 22, 2020
• Publicly Available Date: Jun 23, 2020
• Journal: Journal of Fluid Mechanics
• Print ISSN: 0022-1120
• Electronic ISSN: 1469-7645
• Publisher: Cambridge University Press (CUP)
• Peer Reviewed: Peer Reviewed
• Volume: 897
• Article Number: A32
• DOI: https://doi.org/10.1017/jfm.2020.350
• Keywords: Mechanical Engineering; Mechanics of Materials; Condensed Matter Physics; High-Speed Flow; Shock Waves; Compressible Turbulence
• Public URL: https://uwe-repository.worktribe.com/output/6037365