Publication

Time-frequency analysis of the dynamics of different vorticity structures generated from a finite-length triangular prism

Résumé

Time–frequency analysis of the dynamics of different wake vorticity structures, generated from a triangular prism orientated with its apex edge against the incoming wind, is carried out. Time–frequency analysis of time-series obtained with hot-wire anemometry is performed through a procedure based on proper orthogonal decomposition and spectral components are extracted with a technique that provides an increased efficiency for fluid dynamic applications.

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Concepts associés (32)
Time–frequency analysis
In signal processing, time–frequency analysis comprises those techniques that study a signal in both the time and frequency domains simultaneously, using various time–frequency representations. Rather than viewing a 1-dimensional signal (a function, real or complex-valued, whose domain is the real line) and some transform (another function whose domain is the real line, obtained from the original via some transform), time–frequency analysis studies a two-dimensional signal – a function whose domain is the two-dimensional real plane, obtained from the signal via a time–frequency transform.
Time–frequency representation
A time–frequency representation (TFR) is a view of a signal (taken to be a function of time) represented over both time and frequency. Time–frequency analysis means analysis into the time–frequency domain provided by a TFR. This is achieved by using a formulation often called "Time–Frequency Distribution", abbreviated as TFD. TFRs are often complex-valued fields over time and frequency, where the modulus of the field represents either amplitude or "energy density" (the concentration of the root mean square over time and frequency), and the argument of the field represents phase.
Domaine fréquentiel
Le domaine fréquentiel se rapporte à l'analyse de fonctions mathématiques ou de signaux physiques manifestant une fréquence. Alors qu'un graphe dans le domaine temporel présentera les variations dans l'allure d'un signal au cours du temps, un graphe dans le domaine fréquentiel montrera quelle proportion du signal appartient à telle ou telle bande de fréquence, parmi plusieurs bancs. Une représentation dans le domaine fréquentiel peut également inclure des informations sur le décalage de phase qui doit être appliqué à chaque sinusoïde afin de reconstruire le signal en domaine temporel.
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MOOCs associés (11)
Digital Signal Processing I
Basic signal processing concepts, Fourier analysis and filters. This module can be used as a starting point or a basic refresher in elementary DSP
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