Numerical modeling of droplet formation for weakly elastic fluids using level set model

The significant interest in 3D printing and coating technology requires a more profound knowledge of the complex droplet formation process. The complex topological behavior of capillary-driven thinning and pinch-off during the droplet formation becomes even more complex by adding a minute amount of polymers. The present study aims at modeling the droplet formation of weakly elastic fluids in the dripping regime. To this end, the level set model is employed for interface tracking while an axisymmetric computational domain is used to reduce the computational cost. The Oldroyd-B model is used to take into account the viscoelastic effects. Numerical modeling is conducted for fluids with identical shear viscosity while the elastic properties change. The obtained numerical results are compared against the available experimental data to evaluate the accuracy of the solution. In addition, the influence of the elastic properties of the fluid on the interface evolution is investigated. Furthermore, the transition from the inertio-capillary to the elasto-capillary regime before the pinch-off moment is discussed.