Particle-level simulation is used to predict the motion of short glass fibers in a center-gated disk during injection molding to evaluate its applicability to the prediction of the fiber orientation distribution. The interaction of the flexible fibers is included in the simulation, and the experimentally obtained fiber length distribution and inlet orientation are used as initial conditions. In the sprue, the aligned orientation at the inlet is predicted to become random when the fibers reach the bottom because of the diverging flow. In the disk, the fibers are mainly oriented perpendicular to the flow, and the orientation profile along the thickness is found to change from asymmetric to symmetric about the channel center with increasing radial position. These predicted orientations closely match the experimental results obtained by X-ray micro-computed tomography. It is also demonstrated that the particle-level simulation successfully reproduces the dependence of the fiber orientation on the fiber length.

粒子级模拟用于预测注塑过程中中心门控圆盘中短玻璃纤维的运动，以评估其在预测纤维取向分布中的适用性。仿真中包括了柔性纤维的相互作用，并将实验获得的纤维长度分布和入口方向用作初始条件。在浇口中，由于流向发散，预计当纤维到达底部时，入口处的对齐方向将变得随机。在圆盘中，纤维主要垂直于流取向，并且沿着厚度方向的取向轮廓随着径向位置的增加而围绕通道中心从不对称变为对称。这些预测的方向与通过X射线微计算机断层扫描获得的实验结果非常匹配。还证明了颗粒级模拟成功地再现了纤维取向对纤维长度的依赖性。