Image pre-processing method for near-wall PIV measurements over moving   curved interfaces

doi:10.1088/1361-6501/aa574c

CORC > 北京大学 > 工学院

	Image pre-processing method for near-wall PIV measurements over moving curved interfaces
	Jia, L. C. ; Zhu, Y. D. ; Jia, Y. X. ; Yuan, H. J. ; Lee, C. B.
刊名	MEASUREMENT SCIENCE AND TECHNOLOGY
	2017
关键词	moving curved interfaces near-wall PIV measurements image transformation adaptive stretching synthetic particles INTERROGATION VELOCIMETRY TURBOMACHINERY IMPROVEMENT TRANSITION FLOWS
DOI	10.1088/1361-6501/aa574c
英文摘要	PIV measurements near a moving interface are always difficult. This paper presents a PIV image pre-processing method that returns high spatial resolution velocity profiles near the interface. Instead of re-shaping or re-orientating the interrogation windows, interface tracking and an image transformation are used to stretch the particle image strips near a curved interface into rectangles. Then the adaptive structured interrogation windows can be arranged at specified distances from the interface. Synthetic particles are also added into the solid region to minimize interfacial effects and to restrict particles on both sides of the interface. Since a high spatial resolution is only required in high velocity gradient region, adaptive meshing and stretching of the image strips in the normal direction is used to improve the cross-correlation signal-to-noise ratio (SN) by reducing the velocity difference and the particle image distortion within the interrogation window. A two dimensional Gaussian fit is used to compensate for the effects of stretching particle images. The working hypothesis is that fluid motion near the interface is 'quasi-tangential flow', which is reasonable in most fluid-structure interaction scenarios. The method was validated against the window deformation iterative multi-grid scheme (WIDIM) using synthetic image pairs with different velocity profiles. The method was tested for boundary layer measurements of a supersonic turbulent boundary layer on a flat plate, near a rotating blade and near a flexible flapping flag. This image preprocessing method provides higher spatial resolution than conventional WIDIM and good robustness for measuring velocity profiles near moving interfaces.; National Natural Science Funds of China [11632002, 11372009, 11602005]; Foundation for Innovative Research Groups of the National Natural Science Foundation of China [11521091]; SCI(E); ARTICLE; 3; 28
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/474952]
专题	工学院
推荐引用方式 GB/T 7714	Jia, L. C.,Zhu, Y. D.,Jia, Y. X.,et al. Image pre-processing method for near-wall PIV measurements over moving curved interfaces[J]. MEASUREMENT SCIENCE AND TECHNOLOGY,2017.
APA	Jia, L. C.,Zhu, Y. D.,Jia, Y. X.,Yuan, H. J.,&Lee, C. B..(2017).Image pre-processing method for near-wall PIV measurements over moving curved interfaces.MEASUREMENT SCIENCE AND TECHNOLOGY.
MLA	Jia, L. C.,et al."Image pre-processing method for near-wall PIV measurements over moving curved interfaces".MEASUREMENT SCIENCE AND TECHNOLOGY (2017).