Techniques for Drop Size Measurement by Direct Photography and Electronic Particle Size Analysis

摘要

A photographic technique is described which overcomes many of the problems encountered in measuring the droplet size distribution in sprays. Droplet photographs were analysed using a Mullard Particle Size Analyser as recommended in the text and it is shown that, for photographs in which the depth of field is less than the spray thickness, a high contrast emulsion leads to errors. In general it is better to avoid out-of-focus drops, but a method is suggested which permits the results to be corrected provided the extent of the spray is large compared to the depth of field. (Author)