三角嵌铺粒子追踪算法的三维化扩展

Extension of the delaunay-tessellation particle tracking algorithm to 3D field

针对连续帧三维流场粒子的匹配问题,对基于三角嵌铺的粒子追踪算法进行了三维化扩展并将其命名为3DT PTV。3DT PTV遵循从粒子样型匹配到粒子匹配的原则,即粒子匹配结果从粒子样型匹配结果中总结。首先通过自定义"粒子样型DT网格"实现了粒子样型匹配的参数无依赖性,使3DT PTV适用于粒子非均匀分布流场;其次通过自定义"样型唯一性标识向量"进行粒子样型匹配;最终通过"双向计算-概率择优"模块对样型匹配结果进行样本扩展并整合出粒子匹配。通过添加自定义干扰的JPIV人工流场对3DT PTV进行了检验。除了算法本身的简洁性,结果亦证明了3DT PTV处理粒子无匹配率较高的复杂流动的良好特性。

The particle tracking velocimetry （PTV）algorithm based on Delaunay Tessellation （DT）, named as 3DT PTV is improved to match particles from two consecutive instants in the three-dimensional field.In 3DT PTV,the particle pairing is summarized out of the pattern pairing,in which a pattern DT grid is adopted in the selection of pattern candidate to enable 3DT PTV free of parameters and applicable in unevenly distributed flow,and a pattern identifying vector is proposed for the pattern similarity judgment. The result of particle pairing is then doubled and refreshed by the processors of “Dual Computation”and“Selection by Probability”.3DT PTV is tested by standard synthetic flows with self-defined perturbations. The merit of 3DT PTV confirmed by the test result is the high accuracy in addressing complex flow with noticeable ratio of particles having no pair.