针对航空发动机软壁包容机匣用的Kevlar49机织织物，基于Ivanov提出的单胞模型，采用三元件粘弹性本构模型描述纱线应变率相关的力学特性，建立了Kevlar49织物高速冲击数值仿真模型；通过对单个单元拉伸进行数值仿真获得Kevlar织物的应力应变响应；对钢球撞击四边固支的单层织物开展了数值仿真计算。结果表明：所建立的基于单胞结构的数值仿真方法既能描述织物的宏观力学特性，又可反映出撞击过程中纱线的相互运动；单元拉伸仿真获得的拉伸应力应变响应与试验结果一致；Kevlar织物在钢球下的冲击响应与法向变形与纱线细观有限元模型结果一致，验证了发展的基于单胞模型的数值仿真方法的有效性。%The high speed impact numerical simulation model of Kevlar49 fabric, which is employed by the soft wall containment case of aeroengine, were developed based on the unit cell simpliifed model proposed by Ivanov. The strain rate dependent mechanical property were described by employing the three-element visco-elastic constitutive model. The stress-strain response of Kevlar 49 fabric were obtained by one-element tensile simulation, and the simulation of single layer fabric clamped in its four edges impacted by steel sphere were conducted. The numerical results indicates that the developed unit cell model can describe the macro-scale mechanical property and relfect the yarn movement during impact; The stress-stain response predicted by one-element tensile simulation correlates well with the test results; The impact response and fabric normal deformation predicted by this simulation method agrees well with that predicted by 3D meso-scale model, which validate the effectiveness of the simulation method based on unit cell.
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