Hydrodynamics of Droplet Impingement on a Thin Horizontal Wire

A model of droplet impacting on a thin horizontal wire is developed and numerically analyzed via level set method (LSM). Through varying the impact velocity, the flow regimes of droplet impacting on the wire are examined and analyzed. The detailed hydrodynamic behaviors including transient velocity and pressure distributions as well as the evolution of the gas-liquid interface during droplet impingement are investigated. The results indicate that the hanging mode, merging mode, and splitting mode appear during the droplet impingement on a thin horizontal wire. In merging mode , the tiny bubbles converge to big bubbles arising from the inertia difference between the liquid and the gas make. Due to the dynamic equilibrium between the friction of the thin wire and the droplet surface tension, the double reflux zone and the high-pressure zone are only observed in hanging mode rather than in merging mode and splitting mode. The flow regimes diagram depending on We and Bo is provided to represent the flow regimes of droplet impacting on a thin horizontal wire. The corresponding exponential correlations are given in form of We = a e bBo to distinguish the boundaries between these droplet flow regimes.