Wavelet analysis of the turbulent flow over the very rough surface

Abstract

Wavelet analysis is applied to data from PIV measurement in order to recognize a specific structure in the flow. The PIV snaphots achieved on the model of the street canyon was used as a test case. Four flow characteristics that are at disposal from one-point simultaneous two-components measurement (e.g. from 2D LDA) were analyzed by Wavelet method: longitudinal and vertical velocity, momentum flux u’w’ and δS – the difference between momentum fluxes associated with a sweep and an ejection. Each of characteristic is useful for detection of certain type of event. We have focused on the sweep and the ejection that seem to be the most convenient for investigation of a significant inflow or an outflow from the street canyon.