3D Particle Image Processing Based On Stereo Vision

Particle Image Velocimetry is one kind of untouched measurement technology for flow field. So far 2D-PIV is a mature technique. It has already been applied to two-dimensional flow field measurement of hydrodynamic experiments and aerodynamic experiments. In the actual flow, Fluid movement takes on the feature of 3D space. 3D-PIV can accurately reveal various flow phenomenona, it makes 3D-PIV theory and application become the key point of research. With the technique improvement, focus is mainly put on four aspects: flow visualization, vision measuring technique, speckle measurement and image processing. In modern industrial field, 3D-field measurement based on stereo vision is a new technique in vision measurement, especially in 3D contour and volume measurement has a wide prospect in application.The preliminary study about application of arithmetic based on stereo vision in PIV is carried out. The main work is as follows:Firstly, stereo vision system is introduced in detail, which consists of geometry point, system structure, system constitute and math model. Secondly, on the basis of stereo vision system structure and math model, image capture system is established, and hardware constitution is introduced. Thirdly, this paper mainly discusses camera calibration, feature extraction, stereo matching and 3D reconstruction, link the characteristic of particle image, selects appropriate algorithms, such as calibration of Zhang, phase correlation matching and 3D reconstruction, they form 3D particle image processing system. Finally, an experiment platform is developed on Matlab, it successfully implements critical parameters of spatial particle 3D information. The practical experiment verifies the result of measurement is good.