预压缩强度对冲击波在颗粒链中传播特性的影响
时间:2018-05-05 16:43 来源:毕业论文 作者:毕业论文 点击:次
| 摘要对冲击波在单一颗粒链的传播特性进行分子动力学方法模拟。结果发现，预压缩强度对冲击波传播的形貌、速度、能量分布都有影响。当预压缩强度较小时，冲击波在颗粒链中以孤立波模式传播，波的动能与势能的比值保持 0.56 不变；当预压缩强度中等时，冲击波主要以孤立波和准谐波模式传播，波的动能与势能的比值随着预压缩强度的增大而减小；当预压缩强度较大时，冲击波以准谐波模式传播，波的动能与势能的比值保持 0.5 不变。根据本文的结果，通过改变相邻颗粒间的初始预压缩量，可以实现调控冲击波在预压缩颗粒链的传播过程中孤立波的传播速度和颗粒链的能量分布，相信该结果对研制新型力学缓冲器和声整流器等有着重要的参考价值。22269 毕业论文关键词 颗粒链； 孤立波； 预压缩； 长波近似； 二体碰撞近似 Title Effect of Pre-compression Intensity on the Propagation of Shock Wave in Granular Chain Abstract Studied the shock wave propagation characteristics in the granular chain using molecular dynamics method. The results shows that pre-compression intensity has an effect on the morphology, velocity and energy distribution of the shock wave propagation .When the smaller pre-compression, shock wave propagates mainly in solitary wave mode in the granular chain, The ratio of kinetic and potential energy remains 0.56 unchanged; When the medium pre-compression, shock wave propagates mainly in solitary wave and quasi-harmonic mode. The ratio of the kinetic and potential energy of the wave decreases with pre-compression intensity increasing; When the larger pre-compression, the shock wave mainly propagates in quasi-harmonic mode, The ratio of kinetic and potential energy remains 0.5 unchanged. According to the results of this paper, by changing the initial pre-compression between adjacent granular , can regulate and control propagation velocity and energy distribution of solitary wave when the shock wave propagating in the pre-compressed granular chain, I believe that the results has an important reference value on the development of new mechanical buffer and acoustic rectifier device. Keywords granular chain； solitary wave； pre-compression long-wavelength approximation； binary collision 目 次 1 绪论1 1.1 颗粒物质简介以及孤立波在一文颗粒链传播的研究现状1 1.2 本文主要研究内容3 2 一文颗粒链的非线性描述3 2.1 颗粒间的相互作用3 2.2 一文水平颗粒链中孤立波的理论描述5 2.2.1 长波近似5 2.2.2 二体碰撞近似10 2.3 一文颗粒链中孤立波的研究方法对比12 2.4 对颗粒物质的模型描述14 3 二体碰撞研究预压缩颗粒链中的孤立波传播特性17 3.1 预压缩下的碰撞模型和二体碰撞近似17 3.2 预压缩强度对冲击波传播特性的研究19 3.2.1 预压缩强度对冲击波形貌的影响20 3.2.2 预压缩强度与冲击波速度的关系21 3.2.3 预压缩强度对冲击波能量分布的影响22 结论26 致谢27 参考文献28 1 绪论 1.1 颗粒物质简介以及孤立波在一文颗粒链中传播的研究现状 地球上的颗粒物质广泛存在且数量巨多。例如自然界中广泛存在的土壤、砂石、 冰雪；生活中常用的食盐、谷物粮食、药品颗粒等；极端天气条件下出现的北方肆虐 (责任编辑：qin) |