Characteristics of a developing droplet - Laden jet impinging on a normal wall

The size-velocity characteristics of a droplet-laden air jet impinging on a normal wall is investigated using a phase-Doppler anemometer. The results of measurements conducted for two jet-exit-to-impingement-wall distances ar e presented. Experimental data are obtained across the jet at several axial stations covering the first ten jet-exit diameters. The radial variation o f droplet mean velocity, rms velocity and skewness coefficient indicates th at similarity is not achieved. The rate of spreading of the jet is higher t han that noticed in both single-phase flow and previous two-phase flow stud ies. The presence of the impingement wall does not have a significant effec t on the mean velocity distributions for Z/Z(i) < 0.8. There is an increase in droplet size with increasing distance from the nozzle for Z/D > 4.0. In the early regions of the jet, the water droplet size and velocity are stro ngly correlated, especially in the core regions. With increasing Z/D, there is no association between size and velocity.