Director of Research, Delavan Inc, West Des Moines, IA
Pages: 8 Published: Jan 1986
For many years, coated slides, sensitized paper and cards, collection cells, impaction devices, and high-speed photographs were utilized to estimate the size of droplets in agricultural sprays. Developments in laser optics, solid-state imaging, and integrated circuits have now led to a new generation of sophisticated instruments for sizing liquid particles. Based on holography, light scattering, interferometry, and imaging, and linked with computerized data reduction systems, these instruments are generally capable of rapid, nonintrusive measurements. Researchers, however, must still cope with such considerations as calibration, data repeatability, and accuracy. Erratic data and disagreement between instruments are persistent problems that have surfaced during informal comparisons and in organized round robins. These difficulties do not necessarily indicate faulty equipment. Most instruments have inherent limitations that may involve permissible ranges of particle size, velocity, and flux. Sampling and data reduction procedures also affect results. Droplet size analysis has not yet become truly automatic. Experience and judgment are necessary ingredients in the quest for valid data.
liquid atomization, spray nozzles, droplet size, sampling, instruments, optics, data analysis
Paper ID: STP18362S