Simulations of interface evolution and stress distribution near weld line in the viscoelastic melt mold filling process are achieved according to the viscoelasticNewtonian twophase model. The finite volume methods on nonstaggered grids are used to solve the model. The level set method is used to capture the melt interface. The interface evolution of the viscoelastic melt in the mold filling process with an insert in is captured accurately and compared with the result obtained in the experiment. Numerical results show that the stress distribution is anisotropic near the weld line district and the stress distribution varies greatly at different positions of the weld line district due to the complicated flow behavior after the two streams of melt meet. The stress increases quickly near the weld line district and then decreases gradually until reaching the tail of the mold cavity. The maximum value of the stress appears at some point after the insert.
The plastic mold filling process produces large numbers of parts of high quality. Plastic material in the form of granules is melted until it is soft enough to be injected under pressure to fill a mold. Early simulations of mold filling process mostly used the HeleShaw model coupled with the finite element method, which is based on the creeping flow lubrication model [
The viscoelastic behaviour in mold filling process has been tested in [
We use the corrected level set method proposed by Sussman et al. [
where
Here,
Here,
The governing equations for the flow field with the consideration of fibers are given as follows.
Continuity
where the Reynolds number
Constitutive
Here, the extended PomPom (XPP) constitutive equation developed by Verbeeten et al. [
Definition of the constants and functions in the constitutive equation [
Equation 






We 




We 




We 




We 



Proper boundary conditions must be posed on the solid walls of the cavity. In this paper, noslip boundary conditions are used for the velocities, that is,
Level set evolution equation (
The finite volume SIMPLE methods on a nonstaggered grid are used to solve the governing equations (
The validity of the methods has been verified in [
Figure
Sketch map of the mold with an insert in.
Computational domain of the mold.
Figure
Melt positions at different time in the mold filling process.
From Figure
Comparison between the interface evolution after the insert and that obtained in experiment.
In order to get the stress distribution and make a comparison with the experimental results given by the stress birefringence distribution, we use the formula in [
Here,
Figure
The distribution of the stress birefringence at
The stress distribution birefringence obtained in experiment [
Figure
The change of the stress birefringence from the tail of the insert until the end of the cavity.
In this paper, simulations of interface evolution and stress distribution near weld line in the viscoelastic melt mold filling process are achieved according to the viscoelasticNewtonian twophase model established by Yang et al. [
All the authors would like to acknowledge the National Natural Science Foundation of China (10871159), National Natural Science Foundation of Shanxi (20120110192), and Doctoral Foundation of Taiyuan University of Science and Technology (20112011).