Streak growth in high-speed boundary layers: assessment through the compressible boundary region equations

Adrian Sescu, Mohammed Afsar, Yuji Hattori

Research output: Contribution to conferencePaper

1 Downloads (Pure)

Abstract

Streamwise vortices and the associated streaks evolve in boundary layer flows over flat or concave surfaces as a result of various disturbances initiated in the upstream or from the wall surface. Following the transient growth, they can lead to secondary instabilities and early transition to turbulence via bursting processes. It is desirable, therefore, to accurately predict and efficiently control the growth of these disturbances in an attempt to reduce the associated frictional drag. In high-speed boundary layers, additional complications are involved due to the compressibility and thermal effects, the level of contribution of which scales with the Mach number. In this work, we study streaks in high-speed boundary layers via the numerical solution to the full nonlinear compressible boundary region equations, which is the high Reynolds number asymptotic extension of the Navier-Stokes equations in the assumption that the streamwise wavenumber of the disturbances is much smaller than the wall- normal and spanwise wavenumbers (this is characteristic to boundary layer streaks). The base flow is excited by freestream disturbances imposed at the upstream boundary, and the growth of the streaks is studied using bi-global stability analysis.
Original languageEnglish
Publication statusPublished - 8 Nov 2019
EventSixteenth International Conference on Flow Dynamics - Tohoku University , Sendai, Japan
Duration: 6 Nov 20198 Nov 2019
Conference number: 16th
http://www.ifs.tohoku.ac.jp/

Conference

ConferenceSixteenth International Conference on Flow Dynamics
Abbreviated titleICFD-2019
CountryJapan
CitySendai
Period6/11/198/11/19
Internet address

Keywords

  • streamwise vortices
  • streaks
  • boundary layer flow

Fingerprint Dive into the research topics of 'Streak growth in high-speed boundary layers: assessment through the compressible boundary region equations'. Together they form a unique fingerprint.

  • Cite this

    Sescu, A., Afsar, M., & Hattori, Y. (2019). Streak growth in high-speed boundary layers: assessment through the compressible boundary region equations. Paper presented at Sixteenth International Conference on Flow Dynamics, Sendai, Japan.