A high-spatial resolution and large dynamic range cross-correlation PIV technique for turbulent flow measurements

This paper describes two variations of a new method of image acquisition with image shifting for PIV. This technique allows two separate images to be recorded on high spatial resolution film or a digital CCD array with a very short time delay between sequential exposures. A novel adaptive CCDPIV analysis method is also described which has a larger velocity dynamic range and better spatial resolution than the standard CCDPIV analysis technique. These image acquisition methods and CCDPIV analysis are applied to the measurement of velocity and vorticity fields for (a) flow separation at a blunt leading edge of a flat plate and (b) a turbulent jet flow.