{
  "id": "physics/0509208",
  "version": "v1",
  "published": "2005-09-24T16:32:02.000Z",
  "updated": "2005-09-24T16:32:02.000Z",
  "title": "Response maxima in time-modulated turbulence: Direct Numerical Simulations",
  "authors": [
    "Arkadiusz K. Kuczaj",
    "Bernard J. Geurts",
    "Detlef Lohse"
  ],
  "comment": "submitted to Europhysics Letters (EPL), 8 pages, 8 Postscript figures, uses epl.cls",
  "doi": "10.1209/epl/i2005-10486-2",
  "categories": [
    "physics.flu-dyn",
    "physics.comp-ph"
  ],
  "abstract": "The response of turbulent flow to time-modulated forcing is studied by direct numerical simulations of the Navier-Stokes equations. The large-scale forcing is modulated via periodic energy input variations at frequency $\\omega$. The response is maximal for frequencies in the range of the inverse of the large eddy turnover time, confirming the mean-field predictions of von der Heydt, Grossmann and Lohse (Phys. Rev. E 67, 046308 (2003)). In accordance with the theory the response maximum shows only a small dependence on the Reynolds number and is also quite insensitive to the particular flow-quantity that is monitored, e.g., kinetic energy, dissipation-rate, or Taylor-Reynolds number. At sufficiently high frequencies the amplitude of the kinetic energy response decreases as $1/\\omega$. For frequencies beyond the range of maximal response, a significant change in phase-shift relative to the time-modulated forcing is observed.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2005-09-24T16:32:02.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "direct numerical simulations",
      "response maximum",
      "time-modulated turbulence",
      "periodic energy input variations",
      "large eddy turnover time"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 8,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}