High Speed and High Resolution PIV for Gray Scale Image using Three Spatio-Temporal Derivatives

Abstract

The brightness distribution cross correlation method which is used widely in PIV measurement for gray scale image takes a long CPU time to obtain the flow velocity due to searching the maximum correlation region. To the contrary, an effective PIV algorithm using spatio-temporal derivatives was proposed by Okuno et al. However it needs a flow field model to supplement the lack of information obtained by two consecutive images. In present paper, a new method using three spatio-temporal derivatives is proposed, in which three consecutive images are used to obtain pure measurement value with short CPU time. The performance of the method is examined by uniform flow, two-dimensional vortex flow and meteorological satellite image.