Mironov D.   Зиновьев В.Н.   Лебига В.А.   Пак А.Ю.   Miau J.  

Application of Hilbert-Huang Transform for Non-Stationary Flow Characteristics Analysis

Reporter: Mironov D.

One of the most important goals of experimental gas dynamics is to study formation and evolution of fluctuations generated by flow over some obstacles. Such fluctuations are mostly non-stationary. To analyze such experimental data time-frequency techniques are required such as wavelet transform and Hilbert-Huang transform. In this paper some results of application of these techniques for data analysis are presented. Specific features, advantages and disadvantages of these transforms are mentioned. Time series were obtained in two different experiments: first –measurements of fluctuation in shallow cavity, second – in the wake behind a cylinder. Characteristic modes of fluctuations for each type of flow were considered. It was found in shallow cavity flow that appearance of high intensity fluctuations is random. Fluctuations behind a cylinder were found to have some specific amplitude modulation.

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