Droplet Sizing Using the Shifrin Inversion
Abstract
A method for measuring droplet size distributions was investigated with an emphasis on limitations related to measurements in real spray environments. The method stores a photographic image of a plane of droplets within a spray and is capable of evaluating particle size distributions within the spray, one small region at a time. The method complements droplet velocity measurements made using Particle Image Velocimetry. In a typical experiment, a plane of the spray was illuminated by a laser light sheet and photographed. After processing, a small laser beam scanned the film and a diffraction pattern was generated for each region illuminated by the small laser. The diffraction pattern was inverted using a Shifrin inversion to solve for the particle size distribution within the illuminated region. When applied to real particle images for either monodisperse or polydisperse particle distributions, the results of the Shifrin inversion are affected by constraints on the range and quality of the intensity data. Some of these constraints are imposed by hardware limitations and some are imposed by the coherent reconstruction system itself In this paper we will discuss some of these limitations and indicate one approach which seems to allow for improved inversions using data signal processing. Experimental data for use with the measurement method was generated using water doped with 2',7' dichlorofluorescein from an atomizer. Particle sizing, Diffraxtion, Shifrin inversion
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1992
- Accession Number
- ADA264644
Entities
People
- P. V. Farrell
- R. Albert
Organizations
- University of Wisconsin–Madison