复杂固体边界流场的三维 PIV 测试技术:任意三维边界识别算法

Three-dimensional PIV measurement technique for complex solid boundary:arbitrary three-dimensional boundary recognition algorithm

  • 摘要: 针对复杂固体边界三维流场的 PIV 测试应用,以及流固耦合实验研究中流场和固体结构特征的瞬态同步测试需求,发展了一种基于双相机布置形式的任意三维边界识别算法以精确获取三维表面几何信息;并以基于MLOS-SMART 三维粒子场重构的 Tomo-PIV 算法计算三维速度矢量场,可同步获取三维表面结构运动/变形信息和三维瞬态速度场。这一边界识别算法基于 SURF(加速稳健特征)模式识别算法进行三维曲面重构,可以确定流场中三维物体结构的边界特征。论文采用双相机布置方式获取了三种不同曲率的圆柱曲面图像,验证了所发展的三维边界识别算法的准确性。最后以圆柱绕流 Tomo-PIV 数字合成粒子图像序列为验证对象,采用所发展的边界识别算法和 Tomo-PIV 算法分别高质量地计算出圆柱曲面信息和三维速度场。

     

    Abstract: A SURF based three-dimensional boundary recognition algorithm has been devel-oped for identifying and reconstructing three-dimensional geometry of arbitrary solid boundaries. This method is used in conjunction with MLOS-SMART three-dimensional particle image recon-struction and three-dimensional cross-correlation algorithms to simultaneously measure the veloc-ity field as well as the boundary geometry.The boundary recognition algorithm was firstly veri-fied by using a set of cylinder images where the exact curvatures were known.The three-dimen-sional velocity field of a cylinder wake was then calculated by CFD and used for generating syn-thetic particle image sets.Finally,the validity and accuracy of the algorithms were verified by processing the synthetic images and comparing the calculated velocity filed and boundary geome-try with CFD data and the exact cylinder dimensions.

     

/

返回文章
返回