Visualisation of statistically periodic coherent structures in turbulent flows using a phase-locked averaging method

Coherent structures are the focus of many flow investigations, although their contribution to turbulent mixing is not well understood. When occurring together with high intense turbulent mixing, these structures require statistical methods for visualisation and analysis of simulation results obtained using high-resolution numerical schemes, such as LES or DES. The method of 'phase-locked' averaging separates transient processes with a given frequency. This paper reveals an online formulation for the phase-locked averaging technique at a certain frequency to be set by the user. The method is demonstrated for two realistic flow configurations, an isothermal double-concentric combustor flow and a jet-in-crossflow situation.

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