光散乱法による非球形粒子の速度と等価直径の同時測定

抄録

A new instrument for evaluating the equivalent diameter and velocity of nonspherical particles was developed. The technique is based on the diffraction light intensity method where the light scattered in the forward direction is insensitive to the particle shape but is related to the projected area of the scatterer. A calibration curve between diameter and scattered intensity was determined by a computer simulation using Fraunhofer diffraction theory and the geometrical optics method. Signal processing had been performed with transient recorders and a digital signal processor, working with a personal computer. Various types of irregularly shaped particles, such as cooper, aluminum oxide, glass, polyethylene and stainless steal with diameters ranging from 20 to 200 μm have been examined. The reference diameter of these particles was evaluated by a microscope with an image processing system. Measured size distribution coincided significantly with the reference data, with uncertainty bands of + 10 μm, -0 μm in average diameter.