A method for measuring the dynamics of velocity vector fields in a turbulent flow using smoke image-visualization videos

Abstract

A new optical method for determining flow-velocity vector fields that allows investigations of unsteady and fast processes is described. The method is based on measuring the displacements of turbulent structures, which are visualized in a light sheet, within a fixed time interval between consecutive video frames. The method was tested using measurements of pulsating-flow velocity. It was shown that the difference between the mean flow velocity in the investigated flow measured using this method and a hot-wire anemometer does not exceed 1%, while the deviation of the rms velocity pulsations is within 4.5%.