大丝束碳纤维束内横向动态渗透率计算方法及数值验证

Calculation method and numerical verification of transverse dynamic permeability in large⁃tow carbon fiber tows

针对现有理论方法无法体现纤维浸润性对渗透率影响的局限性,推导了纤维丝束浸渍过程的毛细压力解析表达式和横向动态渗透率计算公式。采用相场法开展了树脂浸渍纤维丝束过程的数值模拟。结果表明,相场法得到的毛细压力数值解与本文的解析解总体趋势一致且相差较小,证明了本文方法计算毛细压力的可靠性。并开展了纤维体积分数和接触角对动态渗透率的影响研究,结果表明,本文方法能较好地表征纤维浸润性对渗透率的影响,实现了对不同浸渍半径处渗透率的动态预测。相较于现有的渗透率计算方法,本文方法适用性更强、计算结果更为准确。

In view of the limitation that the existing theoretical methods cannot reflect the influence of fiber wettability on permeability,the analytical expression of capillary pressure and the calculation formula of lateral dynamic permeability of fiber tow impregnation process were derived.The numerical simulation of the process of resin impregnated fiber tows was carried out by using a phase field method.The simulation results indicated that the numerical solution of the capillary pressure obtained by the phase field method was consistent with the analytical solution obtained from this paper.This proved the reliability of the developed method.The effects of fiber volume fraction and contact angle on the dynamic per-meability were studied.The results indicated that this method could better characterize the effect of fiber wettability on the permeability and realize the dynamic prediction of the permeability at different impregnation radii.Compared to the existing permeability calculation methods,the developed method is more applicable and the calculation results are more accurate.