PIV error correction

Abstract

 A non-post-interrogation method of reducing subpixel errors and eliminating spurious vectors from particle image velocimetry (PIV) results is presented. Unlike methods that rely on the accuracy or similarity of neighboring vectors, errors are eliminated before correlation information is discarded using available spatial and/or temporal data. Anomalies are removed from the data set through direct element-by-element comparison of the correlation tables calculated from adjacent regions. The result is a processing technique that yields a symmetric correlation profile representing the velocity at the boundary of the combined regions. This correlation based correction (CBC) technique greatly improves subpixel accuracy, and is highly robust to out-of-boundary particle motion, particle overlap, unmatched particle correlations, and electronic and optical imaging noise.