Simulation of self-induced capillary break up of a viscous liquid jet

Abstract

The aim of the study is to reveal the patterns of self-induced disintegration of a viscous liquid jet flowing out at low speed from a capillary hole under microgravity conditions. The research method is numerical modeling of the regularities of self-induced capillary decay using the methods of Lagrange mechanics. Results. A verified technique for numerical simulation of a capillary jet of a viscous liquid based on the methods of Lagrange mechanics. Identified patterns of self-induced decay of a viscous jet under microgravity conditions. Dependence of the length of the undisintegrated part of the jet on the viscosity of the liquid and the velocity of its outflow from the capillary nozzle. Conclusion. The developed numerical simulation technique allows one to correctly and efficiently (from the point of view of the computing resource used) simulate the dynamics of a capillary jet, taking into account complex nonlinear and boundary effects. A pronounced effect of viscosity on the regularities of the disintegration of a jet moving at low speed has been established. The obtained spectral characteristics of perturbations in the jet make it possible to raise the question of the possibility of developing an asymptotic theory of the self-induced decay of a viscous jet.

Keywords

• capillary disintegration of a jet
• capillary waves
• global instability
• liquid droplet-radiator