Spatial analysis of hollow-cone spray dispersion in cross-flow

The present contribution focusses on the spatial distribution of particle during dispersion. Many measurements of the size distribution inside the spray were made using a Phase Doppler Analyzer working with high spatial resolution. Afterwards, the particle size measurements in measurement plans are analysed using a statistical procedure of data analysis, which breaks down particle cloud into groups, using the same concept than “Eulerian Modal Models”, whose decompose the aerosol clouds into different modes or bins. This method is applied to a spray generated with an hollow-cone nozzle, in both quiet ambiance or uniform air flow. The clustering approach allows to identify a cloud of fine particles, that is spatially distinct of the coarse and intermediate particle group. In the quiet atmosphere, coarse particles are concentrated in the periphery of the spray whereas small droplets are confined in the centre, revealing the typical shape of hollow-cone nozzle spray. In uniform air flow, cloud trajectories of coarse, intermediate and fine modes are dissociated, whatever the injection direction, perpendicular or counterflow. The classification facilitates the building of trajectory for each group and localisation of falling regions.