Modeling and simulation of fiber‐reinforced polymer mold‐filling with phase change

Abstract

A gas-solid-liquid three-phase model for the simulation of fiber-reinforced composites mold-filling with phase change is established. The influence of fluid flow on the fibers is described by Newton's law of motion, and the influence of fibers on fluid flow is described by the momentum exchange source term in the model. A revised enthalpy method that can be used for both the melt and air in the mold cavity is proposed to describe the phase change during the mold-filling. The finite-volume method on a nonstaggered grid coupled with a level set method for viscoelastic-Newtonian fluid flow is used to solve the model. The "frozen skin" layers are simulated successfully. Information regarding the fiber transformation and orientation is obtained in the mold-filling process. The results show that fibers in the cavity are divided into five layers during the mold-filling process, which is in accordance with experimental studies. Fibers have disturbance on these physical quantities, and the disturbance increases as the slenderness ratio increases. During mold-filling process with two injection inlets, fiber orientation around the weld line area is in accordance with the experimental results. At the same time, single fiber's trajectory in the cavity, and physical quantities such as velocity, pressure, temperature, and stresses distributions in the cavity at end of mold-filling process are also obtained.

Macroscopic and mesoscopic simulation of polystyrene melt in the filling process of injection molding

“…The Pom‐Pom model and Rolie‐Poly model are suitable for characterizing the rheological behaviors of branched and linear polymer melts. More and more simulation results of the filling process of injection molding based on viscoelastic constitutive equations have been reported in the last decade 13–20 …”