Detecting Localized Periods of Concentrated Turbulence Using Wavelets

Boundary layer windfield measurements collected at Texas Tech’s Wind Engineering Research Field Laboratory often appear to have localized periods of high turbulence, especially when analyzed by time-frequency analysis tools such as spectrograms and wavelets. This paper describes a rigorous statistical approach to confirm the existence of these periods of concentrated turbulence. The approach, based on an extension of the Coherent Structure Detector developed earlier by the authors, is used to analyze twenty-one hours of data. Our approach uses Morlet wavelet analysis to identify potential periods of concentrated turbulence. A new statistical test is then applied to show that these peaks are in fact evidence of localized structures in the signal.