Particle size measurements in sprays

Current emphasis on improving performance and reducing emissions in direct injection compression injection (Diesel) engines demands detailed understanding of high pressure transient sprays. Combustion studies require quantitative information, specifically local droplet sizes and velocities, throughout the spray field. The turbulent and unpredictable nature of the sprays complicates the analysis. Most tools currently available for spray analysis provide qualitative information over a large field of view or quantitative information at a single point in the spray field. This paper discusses the implementation of a diffraction-based diagnostic capable of determining particle size information over the full field. This diagnostic and particle image velocimetry together can provide a spatial map of local particle sizes and velocities in the spray.