【作者】 曹雷；

【导师】 张震宇；

【作者基本信息】 国防科学技术大学 ， 力学， 2010， 硕士

【摘要】 含能材料是核武器与常规武器杀伤、破坏和动力能源的关键性材料,评估含能材料在各种复杂应力条件下的生存能力和安全性具有重要意义。含能材料的损伤对含能材料的力学和爆轰性能有重要影响,通过数值模拟方法研究含能材料时,使用损伤本构模型可以更贴近实际描述其力学本质。本文从含能材料的宏观特性出发,建立了粘弹性统计裂纹损伤本构模型,并进行了数值模拟验证。主要做了以下工作:1、对含能材料损伤本构模型的研究进展进行了充分的调研,在综合考虑了含能材料粘弹性和准脆性宏观力学特性的基础上,将广义粘弹性模型和微裂纹损伤模型耦合起来,建立了粘弹性损伤本构模型。2、基于建立的损伤本构模型,编写了自定义材料模型子程序,利用LS-DYNA主程序提供的接口,将其加入到LS-DYNA中,编译生成了包含可以通用计算的LS-DYNA求解器。3、利用编译生成的LS-DYNA求解器对约束PBX-9501炸药的动态撞击实验进行了数值模拟。将模拟结果与实验数据进行对比,结果表明,试样的准二维表面位移场与实验结果吻合较好,说明该模型用于研究PBX炸药在动态加载下的力学响应是有效的。更多还原

【Abstract】 Energetic materials are key materials in killing, destroying and power resource and widely used in nuclear and conventional weapon. It is a significative work to evaluate the viability and safety of the energetic materials in kinds of complex loading conditions. The damage in the energetic materials has important influence on the mechanical and detonation performance of the energetic materials. When studying the energetic materials using numerical simulation method, constitutive model with damage is much closer to the mechanical essential of the energetic materials. Base on the macroscopical property of the energetic materials, a constitutive model with damage, Visco-SCRAM, is developed and validated by numerical simulation. The main content can be summarized as:1.The literature review of constitutive models with damage of the energetic materials is conducted systematically and sufficiently. Based on the integrated consideration of macroscopical viscoelasticity and quasi-brittleness of the energetic materials, the general viscoelasticity model and microcrack damage model are coupled together to form a constitutive model with damage.2.Based on the constitutive model with damage which has been developed, a user-defined material model subroutine is finished. Using the interface that the LS-DYNA main program provides, the subroutine is implemented into LS-DYNA. A LS-DYNA solver which contains the constitutive model and can be generally used is compiled and built.3.The experiment, dynamic impact of confined PBX-9501 high explosive, is numerically simulated using LS-DYNA solver compiled and built. The comparison between the simulation result and experimental data shows that the quasi-planar displacement field in the simulation is coincident well with the one in the experiment. The result indicates that the constitutive with damage exhibits good veracity and validity in simulating the mechanical response of PBX in dynamic loading.更多还原