# Analysis of Fluid Flows via Spectral Properties of the Koopman Operator

@article{Mezi2013AnalysisOF, title={Analysis of Fluid Flows via Spectral Properties of the Koopman Operator}, author={Igor Mezi{\'c}}, journal={Annual Review of Fluid Mechanics}, year={2013}, volume={45}, pages={357-378} }

This article reviews theory and applications of Koopman modes in fluid mechanics. Koopman mode decomposition is based on the surprising fact, discovered in Mezic (2005), that normal modes of linear oscillations have their natural analogs—Koopman modes—in the context of nonlinear dynamics. To pursue this analogy, one must change the representation of the system from the state-space representation to the dynamics governed by the linear Koopman operator on an infinite-dimensional space of…

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