DUAL-MODE PHASE-DOPPLER ANEMOMETER

The accurate measurement of mass flux is identified as being essential for the successful use of phase-Doppler anemometry (PDA) in many appl ications, in particular with sprays. Thus measured sizes of individual droplets and the cross-sectional area to which the flux measurement i s referenced must be reliable. This paper investigates sources of meas urement error in each of these quantities and provides means to elimin ate or minimize these errors. A new PDA configuration, termed dual-mod e PDA, is introduced as an implementation of these suggestions. Exampl e measurements illustrate the advantages of the system over convention al arrangements.