Koopman-mode decomposition of the cylinder wake

  title={Koopman-mode decomposition of the cylinder wake},
  author={Shervin Bagheri},
  journal={Journal of Fluid Mechanics},
  pages={596 - 623}
  • S. Bagheri
  • Published 11 June 2013
  • Engineering
  • Journal of Fluid Mechanics
Abstract The Koopman operator provides a powerful way of analysing nonlinear flow dynamics using linear techniques. The operator defines how observables evolve in time along a nonlinear flow trajectory. In this paper, we perform a Koopman analysis of the first Hopf bifurcation of the flow past a circular cylinder. First, we decompose the flow into a sequence of Koopman modes, where each mode evolves in time with one single frequency/growth rate and amplitude/phase, corresponding to the complex… 
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