任意运动变形边界流场测量PIV算法的研究：薄膜涡激振动

提出了一种精确测量任意运动变形边界流场的粒子图像速度场PIV算法，能智能识别强流固耦合问题流场测量中任意运动变形的边界信息，然后生成贴体自适应的图像互相关计算窗口，计算获取运动变形边界附近的速度场数据。这一算法可大大提高任意运动边界附近流场的测量精度，为流固耦合问题的理论分析和数值计算验证提供可靠的高质量实验数据。针对数字合成给定流场的粒子图像序列，采用所发展的PIV算法对粒子图像区域中的运动变形边界进行了精确识别，高质量地复现了原始流场信息。最后，对低速闭式循环水洞中的钝体尾流柔性薄膜涡激振动现象进行了PIV实验测量，获得了柔性薄膜大变形运动状态下的瞬态流场特征。

Improved PIV algorithm for flow around arbitrarily moving and deforming boundary： vortex-induced vibration of flexible membrane

A state-of-the-art algorithm of the Particle Image Velocimetry （PIV） was proposed to accurately determine the flow field near arbitrarily moving and deforming boundary, which is usually associated with strong nonlinear coupling of fluid-structure interaction. This smart algo- rithm was employed to faithfully track the fluid-structure interface with large deformation; sub- sequently, a body-fitted arrangement of interrogation windows was made and the standard cross- correlation PIV algorithm was applied to get reliable flow field information near the boundary, providing a solid basis for fluid-structure interaction mechanism analysis and validation of numeri- cal calculations. The proposed algorithm went through bench-mark tests by using synthetically generated image pairs, showing the great potential for measuring the fluid flow around arbitrarily moving and deforming interface. Finally, the fluid flow of fluid-structure interaction associated with a flexible membrane, which was placed behind a square cylinder, was measured by PIV; the instantaneous flow fields near the violently moving and deforming membrane were determined.