关于粒子图像测速仪精度的数值测试

摘要

利用数值模拟的方法对粒子图像测速仪的精度问题进行了数值实验。速度场是通过对一个片光源上两次曝光的图像进行互相关处理来得到的。为了研究流体运动的不均匀性对于一个诊断区内速度矢量测量结果的影响，针对五种典型的不均匀性进行讨论。数值实验的结果表明有几种流体运动不均匀性会显著地影响这种粒子图像测速方法的精度。%A numerical test on the accuracy of the particle image velocimetry is conducted.It is assumed that the information of the particle image photographed by double-exposure with a light sheet is processed by correlation method.In order to study the effect of non-uniformity of fluid motion on determination of the velocity vector at an interrogation spot,five typical non-uniform factors are discussed.A statistical method is used to get quantitative estimation.The results suggest that the accuracy of this PIV method is significantly affected by some factors of non-uniform flow.