碳纤维气流扰动展纤器展纤过程仿真与实验
Spreading Process Simulation and Experimental Investigation for a Carbon Fiber Pneumatic Spreader

针对中、大丝束碳纤维材料浸润性差的问题,采用多级气流扰动展纤法对碳纤维材料进行薄层化研究,建立了基于雷诺平均纳维？菜雇锌怂狗匠痰恼瓜似髂诓苛鞒？CFD(Computational Fluid Dynamics)模型,对展纤器内部流动特征进行仿真,得到内部流场的流线、流速分布状态,并分析对展纤过程可能产生的影响。在气流扰动展纤设备上进行实验,研究展纤器的开口宽度、挡风板高度及展纤区域侧板的倾斜角度对展纤过程的影响,通过参数对比实验得到最佳展纤的展纤器结构参数。实验结果表明,当展纤器挡风板高度为10～20 mm、侧板倾斜角度为16°、开口宽度略大于展宽宽度时,展纤过程中可以避免丝束分叉、丝道偏离展纤器中心导致展纤不均的现象,展纤均匀性最好,展宽倍率可达3倍以上。
A multistage pneumatic spreading system was used to spread carbon fiber tows to solve bad invasion of middle and large carbon fiber tows. A computational fluid dynamics(CFD) model of the internal flow field in fiber pneumatic spreader was established based on Reynolds？？averaged Navier？？Stokes equations and the characteristics of the flow pattern in the spreader were simulated and the effects of air flow distribution and lateral velocity on spreading process were analyzed. Experiments were carried out to investigate the effects of the inlet width of the spreader, the height of the wind shield and the tilt angle of the clapboard on spreading process to optimize the structure of the spreader. It is determined that the optimal height of the wind shield and tilt angel of the clapboard are 10～20 mm and 16°, respectively, with a little inlet width. The flaws of branching and spreading uneven resulting from the trace of fiber tow deviating from symmetry plane of the spreader can be avoided. Thin carbon fiber tow shows its good uniformity, and different width can be obtained and the spreading magnification of width can achieve more than 3 times