Particle Tracking Velocimetry Using Laser-Beam Scanning and Its Application to Transient Flows Driven by a Rotating Disk

Abstract

A particle tracking velocimetry (PTV) system has been developed to obtain instantaneous two velocity components on several sections in three-dimensional space. The flow visualization is conducted by means of parallel laser-light sheets created by a scanning laser beam and the visualized particle images are taken by a highspeed video system synchronized with the scanning. In order to obtain higher accuracy in velocity measurements than usual PTV, some improvements are made on the analyzing procedures: the extraction of particle images, the determination of their center points, the derivation of velocity components and others. The present PTV was applied to the transient flows in a cylindrical tank with a rotating disk. As a result, two-dimensional transient flow patterns with large scale disturbances are continuously captured in three-dimensional space.