Phase doppler technique

Methods for analysis of the particle size distribution in the aerosol cloud include techniques such as time of flight measurement (TOE), inertial impaction and laser diffraction. Dynamic light scattering (photon correlation spectroscopy) is confined to particles (in suspension) in the submicron range. In addition to the size distribution, the particle velocity distribution can be measured with the Phase Doppler technique. 

Naqui et. al. [153] describe a phase Doppler technique, for measuring particle velocity and statistcal information about particle size of irregular particles, based on a phase shift signal. The technique works on near back-scatter which leads to a robust set-up under conditions of limited optical access. Preliminary measurements in a crystallizer were presented and good agreement with TSI Aerodynamic particle sizer was found. 

Hardalupas, Y. and Taylor, A.M.K.P., Phase validation criteria of size measurements for the phase Doppler technique. Exper. in Fluids, 17, 253-258 (1994)... 

Roisman, I. V., and Tropea, C. "Flux Measurements in Sprays Using Phase Doppler Techniques." Atomization and Sprays 11, no. 6 (2001) 667-99. 

Shadowgraphs, Mie-scattering, and phase Doppler techniques used to study fuel flux and droplet size distributions. 1 [Pg.681]

The phase Doppler Technique is a laser-based interferometric approach for simultaneously measuring particle size and velocity. This laser-based method is similar to the well-known laser Doppler velocimeter (LDV) and can make these measurements non-intrusively and with high accuracy. The Phase Doppler Particle Analyzer (PDPA) has been successful applied to many difilcult two-phase flow environments with spherical particles including gas-turbine and rocket fuel inlection, cavitation and bubble formation, and similar two-phase flows. ... 

Application of the Phase Doppler Technique to Optically Absorbent Liquids... 

The phase-Doppler technique for simultaneous measurements of diameters and velocities of spherical particles has been successful in the analysis of spray atomization of both water " and molten steel" as well as in the diagnostic of model experiments with glass spheres or bubbles in water flows. ... 

A number of authors have described the phase-Doppler technique for simultaneous measurements of diameter and velocity of spherical particles ". Therefore we confine ourselves to a short description of the PDA and focus our attention on Mie scattering theory and geometrical optics. 

Phase-Doppler technique applied to an optical absorbent homogeneous liquid... 

For all ink concentrations the results of the phase-Doppler technique and photography agree very well. 

Application of Phase-Doppler Technique to Optically Absorbent Liquids Table 4 Comparison of phase-Doppler results and photography, (p = 30 ... 

Note The maximum error in adjustment of the optical set-up leads to an uncertainty in determining the droplet diameter by phase-Doppler technique of about 8 %. The vagueness of photography is in the order of about 6 /im. 

Extension of Phase Doppler Technique to Sizing and Material Recognition of Sub-micron Particles... 

Rheims, J., Wriedt, T., Bauckhage, K., Working Principle and Experimental Results for a Differential Phase-Doppler Technique, Part. Part./Syst. Charact, 1998, 15,219-224. 

---