  We study the spreading of elastoviscoplastic (EVP) droplets under surface
tension effects. The non- Newtonian material flows like a viscoelastic liquid
above the yield stress and behaves like a viscoelastic solid below it. Hence,
the droplet initially flows under surface tension forces but eventually reaches
a final equilibrium shape when the stress everywhere inside the droplet falls
below the resisting rheological stresses. We use numerical simulations and
combine Volume-of-Fluid (VOF) method and an EVP constitutive model to
systematically study the dynamics of spreading and the final shape of the
droplets. The spreading process examined in this study finds applications in
coating, droplet-based inkjet printing, and 3D printing, where complex fluids
such as paints, thermoplastic filaments, or bio-inks are deposited onto
surfaces. Additionally, the computational framework enables the study of a wide
range of multiphase interfacial phenomena, from elastocapillarity to
plastocapillarity.
