{
  "id": "1504.06195",
  "version": "v1",
  "published": "2015-04-23T14:27:20.000Z",
  "updated": "2015-04-23T14:27:20.000Z",
  "title": "Delaying natural transition of a boundary layer using smooth steps",
  "authors": [
    "Hui Xu",
    "Jean-Eloi W. Lombard",
    "Spencer J. Sherwin"
  ],
  "comment": "17 pages",
  "categories": [
    "physics.flu-dyn"
  ],
  "abstract": "The boundary layer flow over a smooth forward-facing stepped plate is studied with particular emphasis on the delay of the transition to turbulence. The interaction between the Tollmien-Schlichting (T-S) waves and the base flow over a single/two forward facing smooth steps is conducted by linear analysis indicating the amplitude of the T-S waves are attenuated in the boundary layer over a single smooth plate. Furthermore, we show that two smooth forward facing steps give rise to a further reduction of the amplitude of the T-S waves. A direct numerical simulation (DNS) is performed for the two smooth forward steps correlating favourably with the linear analysis and showing that for the investigated parameters, the K-type transition is inhibited whereas the turbulence onset of the H-type transition is postponed albeit not suppressed. Transition is indeed delayed and drag reduced for both these transition scenarios suggesting smooth forward facing steps could be leveraged as a passive flow control strategy to delay natural transition.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-04-23T14:27:20.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "boundary layer",
      "delaying natural transition",
      "smooth forward facing steps",
      "forward facing smooth steps",
      "scenarios suggesting smooth forward"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 17,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}