摘要
基于Hamilton原理,提出一个包含射流强度、剪切、应变率效应、动力学黏性、表面张力和速度梯度等多因素耦合的金属射流拉伸运动方程,具体分析了各种失稳因素,并由数值解定量给出其影响大小,以及最不稳定波长与初始应变率乘积λ_mε_0值的变化范围;给出了射流断裂的时间判据和近似理论公式,计算得到的t_b-ε_0曲线与射流实验点、Chou&Carleone拟合公式三者符合较好.
Based on the Hamilton principle, a coupled motion equation of stretching metallic shaped-charge jet is presented to study the effects of yield strength, shear, strain rate, viscosity, surface tension force and velocity gradient on the jet instability, and the results are quantitatively discussed. The value range of non- dimensional λ_mε_0 was obtained to illustrate the product of the wavelength in unstablest solution and initial strain rate. Furthermore, the criterion and approximate theoretical formula of jet breakup time are presented. The theoretical results were in fairly good agreement with the jet experimental data and those from the method developed by Chou and Carleone.
出处
《力学学报》
EI
CSCD
北大核心
2009年第3期361-369,共9页
Chinese Journal of Theoretical and Applied Mechanics
基金
中国工程物理研究院科学技术发展基金重点项目(2007A09001)
国家自然科学基金和中国工程物理研究院联合基金重点项目(10676120)资助.~~
关键词
金属拉伸射流
运动方程
失稳因素
最不稳定波长
断裂时间
stretching metallic jet, motion equation, instability factor, critical wavelength, break-up time
