Flow Characteristics of High-Speed Spray and Entrainment Air : 2nd Report, Effect of Nozzle Configuration

Abstract

There have been many experiments to characterize Diesel fuel spray under steady-state conditions. However, the appropriate number of holes and the hole position on the sac to be used in the experiment are not clear. To address this subject, we investigate Diesel type spray flows using a laser Doppler anemometer (LDA) and a phase Doppler anemometer (PDA). Spray flow characteristics such as mean and fluctuating two-component velocities, two-dimensional distribution of particle diameter and the variation of three parameters at the log-hyperbolic fitting for particle size distribution are given from measured data. Spray jets from four varieties of Diesel nozzle are compared with each other to clarity the differences in spray characteristics between them. The results show that the spray from the single-hole nozzle on top of the sac is distinct from the others.