CFD study of capillary jets under superimposed destabilizing conditions for microdroplet formation

Abstract

Initial numerical studies on the capillary laminar instability of continuous polymeric jets subjected to controlled destabilization and their comparison with experimental results obtained from a microparticle formation technique are addressed. Continuous jet instabilities and drop formation are challenging free-surface flow problems that require sophisticated interface tracking methods. The assessment of a Coupled Volume of Fluid and Level Set (CLSVOF) commercial code and its potential application to more complex systems are considered. The data obtained from the numerical simulations under different operating conditions showed good qualitative results, in agreement with the trends experimentally obtained. Nevertheless, the use of generalized Newtonian models instead of more complex constitutive equations accounting for the polymer viscoelasticity preclude the obtaining of better comparisons. However, it can be concluded that the use of CLSVOF under the described conditions deals reasonably well with the tracking of the interface, making its use adequate in capillary laminar instabilities.