摘要弹丸挤进过程对火炮发射时膛内火药燃烧规律、膛压及初速有重要影响,传统力学解法和常规实验对于研究挤进过程有局限性。本文针对这一问题,运用有限元方法,采用SolidWorks软件建立弹丸和身管的CAD几何模型,利用HyperMesh软件进行三文有限元网格划分,采用考虑弹塑性变形和断裂失效的Johnson-Cook本构模型描述弹带材料的力学行为,定义弹带与身管内壁之间的侵蚀接触算法,以火炮实弹射击时的弹底压力为主动载荷,利用显式动力学有限元软件ABAQUS/Explicit对弹带挤进膛线过程进行数值模拟,得到弹丸在挤进过程中的运动规律、挤进阻力的变化规律以及挤进压力值。在此基础上,分析了摩擦系数对挤进过程的影响,从而为进一步探索弹丸挤进过程的力学机理提供参考。20764
关键词 有限元法 挤进过程 挤进压力 挤进阻力 弹丸运动
毕业设计说明书(毕业论文)外文摘要
Title Simulation for the Dynamic Engraving
Pressure Of The Large Caliber Artillery
Abstract
Engraving process of projectile and engraving force have an important influence on the rule of combustion, the chamber pressure and the muzzle velocity. The traditional mechanical method and the conventional experimental has limitations on the research of the engraving process. Aiming at this problem, the finite element method is used. A CAD geometry model about the projectile and the tube is established with SolidWorks.Then, completing three dimensional finite element mesh with HyperMesh.Usig Johnson-Cook constitutive model which considers elastic-plastic deformation and fracture failure to describe the mechanical behavior of cartridge belt material,define the erosion contact algorithm about the rotating band and the inside-wall of gun tube . Use the projectile base pressure of live firing as the active loading. The explicit dynamic finite element software ABAQUS/Explicit is used to numerically simulate the process of the bearing band squeezing into the rifling. Get the movement rule of the projectile the engraving process ,the change rule of the engraving resistance and the engraving pressure. On this basis, analysis the influence of friction coefficient on the engraving process, so as to provide reference for further exploring the mechanism of the engraving process of projectile.
Keywords Finite element method Engraving process Engraving force Engraving resistance Motion of projectile
目 次
1 绪论 1
1.1 本课题研究的目的和意义 1
1.2 有限元法的发展现状 2
1.3 弹丸挤进的研究现状 3
1.4 本课题研究的主要内容 4
2 弹带挤进膛线过程分析 5
2.1 挤进压力的定义 5
2.2 挤进系统结构分析 5
2.3 弹丸挤进过程受力分析 7
2.4 弹带挤进膛线过程描述 8
2.5 本章小结 10
3 挤进系统的有限元网格划分 11
3.1 有限元网格划分的基本原则 11
3.2 建模软件的选择 12
3.3 弹丸弹带模型的建立 13
3.4 身管膛线模型的建立 14
3.5 本章小结 16
4 挤进系统有限元模型的建立 17
4.1 仿真软件ABAQUS 17
4.2 ABAQUS/Explicit显式积分算法 18
4.3 挤进系统各部分材料属性 18