Coupled algorithms for viscoelastic ink-jet simulations

摘要

Two finite difference algorithms on rectangular grids are provided for viscoelastic ink ejection simulations. The first algorithm is first-order accurate in time, while the second algorithm is second-order accurate in time. Each of these two algorithms seamlessly couples or incorporates several features: (1) a coupled level set-projection method for incompressible immiscible two-phase fluid flows; (2) a higher-order Godunov type algorithm for the convection terms in the momentum equations and level set convection equation; (3) the central difference for viscosity, surface tension, and upper-convected derivative terms; (4) an equivalent circuit for inflow pressure (or inflow rate). In the first algorithm, a simple first-order upwind algorithm is designed for the convection term in the viscoelastic stress equations. But in the second algorithm, a second-order Godunov type upwind scheme is employed for the convection term in the viscoelastic stress equations.