Development of Single-Frame PIV Velocity Field Measurement Technique Using a High Resolution CCD Camera

Title & Authors
Development of Single-Frame PIV Velocity Field Measurement Technique Using a High Resolution CCD Camera
Lee, Sang-Joon; Shin, Dae-Sig;

Abstract
Although commercial PIV systems have been widely used for the non-intrusive velocity field measurement of fluid flows, they are still under development and have considerable room for improvement. In this study, a single-frame double-exposure PIV system using a high-resolution CCD camera was developed. A pulsed Nd:Yag laser and high-resolution CCD camera were synchronized by a home-made control circuit. In order to resolve the directional ambiguity problem encountered in the single-frame PIV technique, the second particle image was genuinely shifted in the CCD sensor array during the time interval dt. The velocity vector field was determined by calculating the displacement vector at each interrogation window using cross-correlation with 50% overlapping. In order to check the effect of spatial resolution of CCD camera on the accuracy of PIV velocity field measurement, the developed PIV system with three different resolution modes of the CCD camera (512 $\small{{\times}}$ 512, lK $\small{{\times}}$ IK, 2K $\small{{\times}}$ 2K) was applied to a turbulent flow which simulate the Zn plating process of a steel strip. The experimental model consists of a snout and a moving belt. Aluminum flakes about $\small{1{\mu}m}$ diameter were used as scattering particles for the liquid flow in the zinc pot and the gas flow above the zinc surface was seeded with atomized olive oil with an average diameter of 1-$\small{3{\mu}m}$. Velocity field measurements were carried out at the strip speed $\small{V_s}$=1.0 m/s. The 2K $\small{{\times}}$ 2K high-resolution PIV technique was significantly superior compared to the smaller pixel resolution PIV system. For the cases of 512 $\small{{\times}}$ 512 and 1K $\small{{\times}}$ 1K pixel resolution PIV system, it was difficult to get accurate flow structure of viscous flow near the wall and small vortex structure in the region of large velocity gradient.
Keywords
Particle Image Velocimetry;Image Shift;High Resolution Camera;Single-Frame;Cross-Correlation;
Language
Korean
Cited by
1.
아연도금강판의 품질향상을 위한 도금욕 내부 유동제어 연구,최재호;고민석;김석;이상준;

대한기계학회논문집B, 2001. vol.25. 10, pp.1392-1399
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