CHARACTERIZATION OF THE INITIAL SPRAY FROM LOW-WEBER-NUMBER JETS IN CROSSFLOW

An experimental study on the initial spray from a liquid jet in air crossflow was conducted using shadowgraphy and particle tracking velocimetry (PTV) techniques. Momentum flux ratio and gas Weber number were varied to study their effects on the column trajectory, spray trajectory, breakup locations, and spray characteristics after column breakup. Correlations for column trajectory, spray trajectory, and breakup locations in terms of momentum flux ratio and gas Weber number were obtained using linear regression of the experimental data. Two breakup mode regimes were explored in the tests (column breakup and bag breakup). Breakup mode transition from column to bag breakup was found to occur at larger gas Weber numbers than previous studies. Drop characteristics in the spray were also investigated. Drop size measurements revealed bimodal drop size distribution in column breakup mode, while bag breakup mode drop size distribution exhibited single-peak behavior. The characteristic velocity was found to increase more quickly in the column region than in the spray region.