On the volumetric reconstruction of transiting wakes using stereoscopic-PIV

Abstract

The error resulting from volumetric reconstructions of a transiting-model wake through a stationary stereo particle image velocimetry plane has been investigated. First, reconstruction error was evaluated analytically using two canonical, time-dependent flows representative of coherent structures typically found in turbulent wakes. The effects of sampling rate and structure parameters were investigated in reconstruction of a standing wave as well as a diffusing Lamb–Oseen vortex. Reconstruction error was found to be dependent on the length and time scales of these coherent structures, as well as the sampling rate of the measurement system itself. Subsequently, four non-dimensional groups were then identified to define the reconstruction error of these generalized flows. These non-dimensional groups can be used to assist in the design of experiments, by means of estimating error associated with reconstruction of transiting wakes. Finally, a transiting delta wing, travelling at Re $$=300{,}000$$, was analyzed in the context of these aforementioned non-dimensional reconstruction parameters. Unsteady shear-layer interactions were found to incite the largest reconstruction error due to their fast temporal scales relative to the scanning speed.