近距离DPIV粒子成像分析

在PIV(Particle Image Velocimetry)近距离拍摄中,通过对在非傍轴成像条件下薄透镜成像公式的推导,求得粒子图像成像点的近似解析解,对粒子图像的成像位置在PIV图像计算中的影响作了讨论;同时也对已知直径粒子进行了试验拍摄,将试验所得的数据与理论推导的结果进行了比较,对在近距离拍摄中光圈对粒子成像的影响给出了定量分析.

Image Acquisition Research in DPIV

This paper firstly proposes the phenomena that the diameter of particle image obtained is larger than usual with the increase of aperture stop diameter in short object distance image acquisition in PIV measurement which was called spherical aberration. Then the solution was acquired directly by resolving the non line formula of image acquisition through one positive thin lens and the relation between the aperture stop and the spherical aberration was computed. Finally the ideal particle image could be acquired by making use of spherical aberration properly in the aim of sub pixel calculation in PIV and the analysis was also proved by actual experimental results.