# Koopman-mode decomposition of the cylinder wake

@article{Bagheri2013KoopmanmodeDO, title={Koopman-mode decomposition of the cylinder wake}, author={Shervin Bagheri}, journal={Journal of Fluid Mechanics}, year={2013}, volume={726}, pages={596 - 623} }

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…

## 215 Citations

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