Disintegration of Free-falling Liquid Droplets, Jets, and Arrays in Air

A major challenge of irrigating limited areas by dropping liquid from a high altitude using aviation is to ensure the required droplet size distribution of the aerosol immediately before contact with the surface to be irrigated. Varying the initial liquid volume and the drop height can provide different droplet sizes in an aerosol cloud when it reaches the irrigated surface. However, it is extremely difficult to predict such aerosol characteristics when using local drop systems. This requires reliable experimental data on the size to which liquid droplets can be atomized when free-falling in a gaseous medium with a variable initial volume and length of the flight path. This paper presents the results of the experimental research into the transformation and subsequent disintegration of free-falling droplets, jets, and non-sprayed arrays of liquid in gas. Using the experimental results, we determined the minimum, average and maximum droplet sizes in the forming aerosol cloud after the deformation and subsequent disintegration of the falling liquid array. When generalizing the experimental findings, we obtained the empirical equation coefficients making it possible to reliably predict the average sizes of liquid droplets when they are dropped as non-sprayed arrays, jets and aerosols from different heights. The research findings can be used to develop effective technologies for supplying liquids with different initial volumes from variable drop heights into the required area, for example, when extinguishing fires or irrigating various areas. Graphical abstract