Asymmetric instability of a liquid jet

Abstract

The existing aerodynamic theory is not capable of predicting the phenomenon of nonaxisymmetric breakup of a liquid jet, which has long been observed in experiments. A dispersion equation that accounts for the growth of asymmetric waves is derived in this paper. It is demonstrated that there exists a critical Weber number, below which the nonaxisymmetric disturbance becomes unstable. The Weber number here is defined as the ratio of surface tension force to the inertial force. The present theory indicates the possible growth of sinuous wave and the subsequent formation of curling flat sheet from an axisymmetric jet. According to the present analysis for a high-speed jet, the drops break away from the jet surface, instead of rings as predicted by the theory based on the axisymmetric assumption. © 1992 American Institute of Physics.