Proper Orthogonal Decomposition of the mixing layer flow into coherent structures and turbulent Gaussian fluctuations

Abstract The Proper Orthogonal Decomposition is used to decompose fluctuating turbulent flows into a coherent non-Gaussian component and background fluctuations. An application is performed from 2D experimental data of a turbulent plane mixing layer flow. The analyses of the energy spectra and the Probability Density Function of the velocity field show that POD extracts an incoherent part approaching the quasi-Gaussian distribution properties. The background fluctuations are homogeneous with small amplitude. New future applications are then conceivable like the modeling of the incoherent part for particular inflow condition generation methodology and the analysis of the cyclic velocity field variabilities in Internal Combustion engine flow. To cite this article: Ph. Druault et al., C. R. Mecanique 333 (2005).