引信系统螺纹连接界面的冲击传递特性模拟方法研究

Study on the Simulation Method of Impact Transmission Characteristics of Threaded Connection Interface of Fuze System

大直径整体螺纹连接是引信安装在侵彻弹的弹体结构的主要形式,螺纹界面的冲击过载传递特性对于引信系统的设计具有重要意义.针对空间螺纹界面冲击传递过程中涉及的几何非线性和复杂接触摩擦状态以及界面分离带来的二次或多次碰撞等问题,设计了螺纹连接试件并建立了精细化有限元仿真模型,并通过大直径霍普金森杆的冲击实验测量数据验证有限元精细模型的有效性.从有限元仿真中获取整个螺纹结构件冲击响应的数值数据,对比内外结构的过载,并通过精细模型研究了预紧力对加速度响应的影响规律.最后针对现有薄层单元简化模型只能较好地模拟螺纹结构线性振动特性而无法准确模拟螺纹冲击传递特性的问题,提出考虑螺纹间碰撞作用的非线性薄层单元简化模型,丰富了螺纹连接简化模型的适用工况.

Large-diameter integral threaded connection is the main installation form of fuze on the penetrator projectile body.The impact transmission characteristics of the threaded interface have important significance for the design of the fuze system.To solve the problems of geometric nonlinearity,complex contact friction state and secondary or multiple collision caused by interface separation in the process of impact transmission at the inter-face of space thread,a threaded connection specimen was designed and a refined finite element simulation mod-el was established.The validity of the refined finite element model was verified by the impact test data of the large-diameter Hopkinson bar.The impact response of threaded structural parts was calculated by finite element simulation,the overloads of internal and external structures were compared,and the influence of preload on the acceleration response was analyzed through the fine model.Finally,regarding the problem that the simplified model of the existing thin-layer element can only simulate the linear vibration characteristic of the threaded structure well but cannot accurately simulate the shock transfer characteristic of the thread,a simplified model of nonlinear thin-layer elements considering the collision between threads was proposed to enrich the applicable working conditions of the simplified model.