粒子图象电影测速技术

本文介绍一种粒子图象电影测速技术,该技术采用机械调制装置及光学透镜,将连续输出的氩离子激光调制成周期性脉冲片光源序列,并与快速照相枪匹配,可以连续拍摄流场一个截面上随时间发展过程中不同瞬态的一系列两次或多次曝光的粒子图象底片,因而不仅可以取得流动一个截面上的瞬时二维速度场,并且可以获得该流动截面速度场发展的时间历程,为定量研究非定常流动随时间的发展特性提供了一种有效途径。

PARTICLE IMAGE CINEMATOGRAPH VELOCIMETRY

The particle image cinematograph velocimetry (PICV)-a new method of 2D velocity field with time history measurement for the unsteady flows is presented here. Using mechanical chopping light pulses of Aron ion laser,which is matched synchronouistically with moving action of a cinematograppy, series of double or multiple exposure images of particles which are seeded in fluid could be recorded in the films sequentially. The recording films are scaned by a auto- interoga-tion system, a series of instantaneous 2D-velocity distribution maps with time history are obtained. Some results in application for a starting vortex flow around a backward step are presented.