Chebyshev Optimized Approximate Deconvolution Models of Turbulence

Iuliana Stanculescu, William Layton

Research output: Contribution to journalArticlepeer-review

Abstract

<p> <p id="x-x-x-x-"> If the Navier&ndash;Stokes equations are averaged with a local, spacial convolution type filter,&varphi;&macr;&macr;&macr;=g&delta;&lowast;&varphi;, the resulting system is not closed due to the filtered nonlinear termuu&macr;&macr;&macr;&macr;. An approximate deconvolution operator DD is a bounded linear operator which satisfies </p> <p> u=D(u&macr;&macr;)+O(&delta;&alpha;), <a title="Turn MathJax on"> Turn MathJaxon </a> </p> <p> where &delta;&delta; is the filter width and &alpha;&ges;2&alpha;&ges;2. Using a deconvolution operator as an approximate filter inverse, yields the closure </p> <p> uu&macr;&macr;&macr;&macr;=D(u&macr;&macr;)D(u&macr;&macr;)&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;&macr;+O(&delta;&alpha;). <a title="Turn MathJax on"> Turn MathJaxon </a> <p id="x-x-x-x-"> The residual stress of this model (and related models) depends directly on the deconvolution error,u&minus;D(u&macr;&macr;). This report derives deconvolution operators yielding an effective turbulence model, which minimize the deconvolution error for velocity fields with finite kinetic energy. We also give a convergence theory of deconvolution as &delta;&rarr;0&delta;&rarr;0, an ergodic theorem as the deconvolution order N&rarr;&infin;N&rarr;&infin;, and estimate the increase in accuracy obtained by parameter optimization. The report concludes with numerical illustrations. </p> </p></p>
Original languageAmerican English
JournalApplied Mathematics and Computation
Volume208
DOIs
StatePublished - Feb 1 2009

Keywords

  • Deconvolution
  • LES
  • Turbulence model

Disciplines

  • Mathematics

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