A Study of Liquid Jets.

Various correlations were examined that have been used in the past for predicting mean droplet sizes generated by a single fluid jet. The correlation were compared with semi-quantitative data obtained from spark photographs and from a particle sizing interferometer. Jet properties were investigated for three types of fluids, i.e., water, Hexane, and a moderately energetic liquid monopropellant LP used in gun applications. The photographic data are only suitable for a semiquantiative analysis due to severe diffraction problems. Some preliminary low velocity droplet data were obtained with the particle sizing interferometer. The results strongly suggest that all correlations overestimate the droplet size and that the best agreement was obtained from a theoretical analysis by Mayer. Some additional studies were also performed on frictional heating and droplet scattering by an electric field. No evidence of ignition of the liquid monopropellant LP from frictional heating was found. Some evidence of droplet scattering by the electric field could be inferred from the photographs.