NOTE ON PARTICLE-SIZE MEASUREMENTS IN 2-PHASE FLOWS

This paper discusses the use of a phase-Doppler anemometer to obtain t he size and velocity characteristics of droplets formed and transporte d in a flashing water jet. In particular, the validation and calibrati on procedures adopted to ensure correct acquisition of experimental da ta are discussed in detail. The methodology involved in choosing the m agnitudes of the various operating parameters of a phase-Doppler anemo meter such as the intensity of the transmitting beams, signal-to-noise ratio, sample size, and sensitivity of the photomultiplier tubes are described. The droplet size and velocity distributions were acquired a t two axial stations covering the width and height of the jet cross-se ction. Attempts were made to identify the proper scaling variables to develop suitable nondimensional parameters to characterize a flashing jet.