PIV Measurement of the flow around a circular blade using a derotating observation

This paper presents the PIV measurement results for the flow around a circular blade revolving in a circular channel. This flow is a model of the flow in a tea-spoon type pump, model that is employed to examine the effect of the motion of the circular blade on the flow characteristic. The flow visualization is carried out under the derotating observation with a reflecting prism that rotates at the half speed of that of a rotating object. The visualization images are digitized into a personal computer to obtain velocity vectors maps using a PIV algorithm, direct cross-correlation method. From the resulting velocity vectors maps, we estimate the time-averaged velocity, the velocity fluctuation and vorticity distributions around the circular blade.