不同流通间隙排布条件下碳纤维束展纤行为研究

为探究不同流通间隙排布条件下气流展纤器内部流场的分布规律及流场内碳纤维束的受力情况,采用离散单元法,将碳纤维离散为纤维微元,对流场中数千纤维微元的扩散特性进行建模。通过将纤维微元所受各力与流体阻力进行量级比较,最终得到纤维微元运动方程。结合展纤工艺设置相应边界条件,利用COMSOL对流体-纤维微元间的相互作用进行数值模拟,研究流通间隙位置对碳纤维束的运动特性的影响。结果表明,随着流通间隙间距离的增大,流场中促使纤维展宽区域的长度增长,有利于纤维持续受力展开。随着最右流通间隙到纤维出口的距离逐渐减小,阻碍纤维展宽区域的长度减小,有利于纤维束的展宽。

Study on spreading behavior of carbon fiber bundles under different fractal flow path conditions

This study focuses on the distribution of flow field inside the airflow spreader and the force on carbon fiber bundles in the flow field under different fractal flow path conditions. The discrete element Method was used to model the spreading behavior of the thousands of filaments in the flow field. The characteristics of the flow field and the motion of the fiber discrete elements were modeled. By comparing the magnitudes of the forces on the fiber discrete elements to the magnitudes of the fluid resistance, equations of motion for the fiber discrete elements were finally established. With the particle tracking module of COMSOL, the fluid-fiber discrete element interaction was simulated numerically by setting the corresponding boundary conditions with the spreading process. The effect of the position of the fractal flow paths on the motion characteristics of the carbon fiber bundle was investigated. The results show that with the increase of the distance between the fractal flow paths, the length of the fiber spreading area in the flow field increases, which is beneficial for fiber spreading. It is found that shortening the distance between the rightmost fractal flow path to the fiber exit and reducing the length of the fiber spreading region help the fiber bundle spreading.