Abstract
Some calculation schemes of spatial gradient for the spatio-temporal derivative method, which was used for sub-pixel displacement detection in PIV measurements, were evaluated. It was found that the second-order central finite difference scheme tends to underestimate the gradient of tracer-particle's intensity, so that it leads to overestimation of sub-pixel displacements. In this study, a combined upstream and downstream finite difference scheme was proposed and evaluated for one-dimensional flow measurements. Furthermore, the proposed scheme was modified for two-dimensional flow. Two important things for small tracer particle PIV images were shown : 1) the direction of the sub-pixel correction should be taken into account, 2) distant pixels should not be used. It was found that the proposed scheme has high accuracy even if images contain some noises.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
