Increasing performance of planar PIV

TL;DR

This paper introduces a simple, practical method to enhance the accuracy and spatial resolution of planar PIV measurements by improving velocity derivative calculations without complex recovery or finite difference schemes.

Contribution

A novel, easy-to-implement method that significantly improves velocity and derivative accuracy in iterative image deformation PIV, increasing measurement resolution.

Findings

Enhanced velocity measurement accuracy

Improved spatial resolution of PIV data

Method avoids complex derivative calculations

Abstract

To date, the iterative image deformation method of PIV for two-pulse measurements is widely used in experimental fluid dynamics due to its robustness in many scientific and industrial applications. However, it has a known limitation associated with the difficulty of image deformation due to errors that occur when calculating the necessary velocity derivatives using higher-order schemes. In this work, we propose a simple method that helps to noticeably improve the accuracy of the measured velocities and their derivatives, and thereby increase the spatial resolution. The method does not require the recovery of erroneous velocity vectors, avoids the numerical calculation of derivatives necessary for the interrogation window deformation using finite difference schemes, and can be easily applied in practice.