Characteristics-of Droplet Pinch-off in Liquid/Liquid Jet Systems

摘要

Natural and periodically forced jets of water/glycerin solution were examined as they flowed into an ambient of immiscible Dow Corning 200 fluid. The dynamics of jet pinch off was investigated for jet Reynolds numbers of order 50. Refractive index matching and laser induced fluorescence were employed to obtain clear images of the interface and the jet interior. Planar velocity fields were obtained by particle image velocimetry. The results showed that the pinch off mode, including whether or not satellites form, depends on the viscosity ratio, jet Reynolds number, and jet Strouhal number. Pinch off angles appear relatively insensitive to Reynolds and Strouhal number, but sensitive to the fluid viscosity ratio.