Particle image velocimetry for the measurement of mean and acoustic particle velocities

A novel method is outlined which allows measurement of the amplitude of oscillation of a sinusoidal sound field and the mean flow using particle image velocimetry. The method involves simplifying the interrogation area in such a way that the autocorrelation function contains tour significant peaks. The accuracy is of the order of half pixel resolution, once a constant offset related to the non-continuous nature of the probability function of a sine wave is taken into account. This constant, which originates from the pixelation of the image, is shown to be 0.85 pixels.