Numerical simulation of three dimensional non-Newtonian free surface flows in injection molding using ALE finite element method

Abstract

This paper presents a scheme for numerical simulation of non-Newtonian fluid flows in three-dimensional injection molding process using arbitrary Lagrangian–Eulerian (ALE) finite element method. The proposed scheme is based on the pressure-stabilized fractional step algorithm for incompressible Navier–Stokes equations. In light of the ALE description, the moving free surface is accurately tracked in a self-adaptive manner by introduction of the moving least square (MLS) surface fitting method to fully determine the movement of the nodes on the moving free surface, meanwhile the mesh distortions are effectively alleviated. By virtue of the ALE method, a local remeshing strategy is developed for the mesh regeneration frequently required in moving free surface flow problems, so that the interpolation errors due to the mesh regeneration process are minimized and occur only limited to some local regions, and the computational cost for the remeshing process is reduced decisively. The numerical examples of three dimensional injection molding flows are presented to demonstrate the capabilities of the proposed numerical scheme.