Transition mechanism behind a backward-facing step in a supersonic flow

Research output: Chapter in Book/Conference proceedings/Edited volumeConference contributionScientificpeer-review

61 Downloads (Pure)

Abstract

The path of laminar-to-turbulent transition behind a backward-facing step (BFS) in the supersonic regime at Ma = 1.7 and Reδ0 = 13718 is investigated using a very well-resolved large eddy simulation (LES). Five distinct stages are identified in the transition process by the visualisation of instantaneous flow. The transition is initiated by a Kelvin-Helmholtz (K-H) instability of the separated shear layer, followed by secondary modal instabilities of the distorted K-H vortices, leading to Λ-shaped vortices, hair-pin vortices and finally to a fully turbulent state around the reattachment location. Spectral analysis and proper orthogonal decomposition (POD) reveal that the low-frequency breathing dynamics also plays a major role in the transition process.

Original languageEnglish
Title of host publicationProceedings of the 11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019
Subtitle of host publication30/07/19 - 2/08/19 Southampton, United Kingdom
Number of pages6
Publication statusPublished - 1 Jan 2019
Event11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019 - Southampton, United Kingdom
Duration: 30 Jul 20192 Aug 2019

Conference

Conference11th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2019
Country/TerritoryUnited Kingdom
CitySouthampton
Period30/07/192/08/19

Bibliographical note

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care
Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Fingerprint

Dive into the research topics of 'Transition mechanism behind a backward-facing step in a supersonic flow'. Together they form a unique fingerprint.

Cite this