气固两相流中固体粒子三维运动轨迹是研究气固两相耦合关系、分析不同大小粒子分布和运动规律的核心参数,也是研究湍流涡结构作用力、边界层效应的一个重要依据.为此建立了微秒级单相机双视角三维流场成像系统,由单摄像机CCD靶面上同时获取的2个不同角度的两相流图像,通过粒子模式识别算法及粒子三维坐标的逆向投影重建算法,重建了两相流中固体粒子团的三维结构,并在此基础上提出了基于立体视觉原理的三维颗粒轨迹重建模型.
Traces of 3D particle motion in gas-solid two-phase flow constitute the key parameter for studying the coupling mechanism of two phases and for analyzing the distribution and the law of motion of differently sized particles, as well as the important foundation for discussing the effects of vortex structure in turbulent flow and that of the boundary layer. The stereo apparatus consists of a high-resolution digital camera and a stereo adapter which is mounted to the front filter ring of the camera. Two-phase images of two different vision angles are simultaneously obtained by the camera's charge coupled device (CCD) chip. Then 3D structure of solid particle clusters in two-phase flow can be reconstructed by pattern recognition algorithm and backwards projection algorithm in 3D coordinates. Based on this model of reconstruction of 3D particle traces is being proposed according the principle of stereoscopic imaging.