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arXiv · 1401.6417

A low-order decomposition of turbulent channel flow via resolvent analysis and convex optimization

R. Moarref·M. R. Jovanovic·J. A. Tropp·A. S. Sharma·B. J. McKeon
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Abstract

We combine resolvent-mode decomposition with techniques from convex optimization to optimally approximate velocity spectra in a turbulent channel. The velocity is expressed as a weighted sum of resolvent modes that are dynamically significant, non-empirical, and scalable with Reynolds number. To optimally represent DNS data at friction Reynolds number $2003$, we determine the weights of resolvent modes as the solution of a convex optimization problem. Using only $12$ modes per wall-parallel wavenumber pair and temporal frequency, we obtain close agreement with DNS-spectra, reducing the wall-normal and temporal resolutions used in the simulation by three orders of magnitude.

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R. Moarref, M. R. Jovanovic, J. A. Tropp, A. S. Sharma, B. J. McKeon. 2014-05-21. A low-order decomposition of turbulent channel flow via resolvent analysis and convex optimization. https://doi.org/10.1063/1.4876195

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