IMPROVING THE PERFORMANCE OF 2-COMPONENT PHASE DOPPLER ANEMOMETERS

The Gaussian beam defect is now a well documented deficiency of conven tional phase Doppler anemometers and leads to significant errors in pa rticle size estimation when the particle size takes on dimensions of t he same order as the measurement volume. In the present paper, an alte rnative operation mode of conventional, two-component phase Doppler an emometry systems is proposed, which removes these errors for many appl ications. The new approach is analysed theoretically and its improved performance is verified experimentally. Furthermore, the effect of a s lit aperture on the trajectory-dependent size measurement has been exp erimentally investigated.