一种基于互相关的三维PIV图像处理方法

An algorithm for three-dimensional PIV based on cross-correlation

本文建立了一种基于互相关技术的三维 PIV图像处理方法 ,在该方法中 ,建立了粒子的图像坐标与空间坐标的关系式 ;利用互相关技术构成连续两时刻三维空间粒子的对应方法 ;通过图像粒子的标定 ,照相机系统的标定、粒子空间坐标的确定、连续两时刻空间粒子的对应、误对应速度向量的判断和消除步骤 ,形成了一个完整的三维 PIV图像处理系统。将本方法运用于日本可视化协会 (VSJ)提供的三维标准图像的处理 ,结果表明 ,无论是低粒子浓度图像还是高粒子浓度图像都具有精度高。

An algorithm for three-dimensional PIV, based on cross-correlation, was developed in this paper. In this method, the equations relating the particle coordinates between image and research space were constructed, the three-dimensional particle coordinates which is based on the theory of minimum quadratic difference was determined, and the method of stereo particle matching was developed. The processing procedure of three-dimensional PIV includes the identification of particles in image, calibration of cameras system, determination of the particle three-dimensional coordinates, stereo particles matching, determination and deletion of spurious velocity vectors and post-processing. The standard three-dimensional image data produced by addition Visualization Society of Japan was tested with this method. The results show that this method is suitable for high particle density or low particle density and it has the merits of high accuracy and stong reliability. In addition, the stereo particle matching method was set up and the determination and deletion of spurious velocity vectors were developed.