TRANSITION TO TURBULENCE IN A OBLIQUE SHOCK-WAVE/BOUNDARY-LAYER INTERACTION AT M=1.5![]() Presentation: Session: Instability and Transition 2 Room: Room A Session start: 15:00 Tue 25 Aug 2015 Andrea Sansica as4v11@soton.ac.uk Affifliation: University of Southampton Neil David Sandham n.sandham@soton.ac.uk Affifliation: University of Southampton Zhiwei Hu Z.Hu@soton.ac.uk Affifliation: University of Southampton Topics: - Instability and transition, - Large eddy simulation and related techniques Abstract: Direct numerical simulations are carried out for different forcing techniques to trigger transition during the interaction between an oblique shock-wave and a laminar boundary-layer at M = 1.5. Three forcing methods are used: a) forcing of oblique unstable modes, whose shape and behaviour are determined by the local linear stability theory, b) broadband free-stream acoustic disturbances, and c) a cold plasma flow control device. While the oblique-mode breakdown is dominant for low-amplitude forcing, long streaky structures drive the transition process in a high-amplitude disturbance environment. LES are also performed on the experimental setup by the Institute of Theoretical and Applied Mechanics (ITAM) from Novosibirsk State University with cold plasma actuation. As well as the disturbance type, the effect of Reynolds number and forcing amplitude will be investigated. |