水下爆炸冲击波数值仿真精度研究  

Numerical Simulation Accuracy Study of Underwater Explosion Shock Waves

作　　者：敖启源 卢熹 姜智雅 康珀阁 AO Qiyuan;LU Xi;JIANG Zhiya;KANG Poge(School of Equipment Engineering,Shenyang Ligong University,Shenyang 110159,China;Shanxi Jiangyang Chemical Company,Taiyuan 030051,China)

机构地区：[1]沈阳理工大学装备工程学院,辽宁沈阳110159 [2]山西江阳化工有限公司,山西太原030041

出　　处：《水下无人系统学报》2024年第1期158-165,共8页Journal of Unmanned Undersea Systems

摘　　要：在水下爆炸数值仿真研究中,网格尺寸和一次项人工粘性系数对冲击波峰值压力计算结果有较大影响。在预定计算精度条件下,快速确定网格尺寸及人工粘性对数值计算意义重大。为此,文中基于LSDYNA有限元软件,建立78 g三硝基甲苯(TNT)二维水下爆炸数值计算模型,重点分析网格尺寸和一次项粘性系数对水下爆炸冲击波峰值压力和整体计算误差的影响规律。结果表明,随着网格密度因子的增大,计算峰值压力对网格的敏感性降低,且网格密度较大时,过小的一次项系数会导致计算峰值压力与经验公式值的相对误差增大。在此基础上获得20%范围内误差与网格尺寸、粘性系数之间的关系,并构建出可用于快速确定网格尺寸和一次项人工粘性系数的误差预估模型,通过0.2~5000 kg范围内的TNT柱形装药(长径比为1)和球形装药的水下爆炸计算,验证了预估模型的普适性,可为二维中近场范围内的水下爆炸冲击波数值仿真计算研究提供参考。In the numerical simulation study of the underwater explosion,the grid size and the artificial viscosity coefficient of the primary term have a large impact on the calculation results of the peak pressure of the shock wave.Under the condition of predetermined calculation accuracy,it is of great significance to quickly determine the grid size and artificial viscosity for numerical calculation.For this reason,based on LS-DYNA finite element software,a two-dimensional underwater explosion numerical calculation model of 78 g trinitrotoluene(TNT)was established to analyze the influence of the grid size and the viscosity coefficient of the primary term on the peak pressure of the underwater explosion shock wave and the overall calculation error.The results show that with the increase in the grid density factor,the sensitivity of calculated peak pressure to the grid decreases.When the grid density is larger,a small primary term coefficient will cause the relative error between the calculated peak pressure and the empirical formula value to increase.On this basis,the relationship among the error,grid size,and viscosity coefficient within 20%is obtained,and an error prediction model that can be used to quickly determine the grid size and the artificial viscosity coefficient of the primary term is constructed.Through the underwater explosion calculation of cylindrical TNT charge(aspect ratio of 1)and spherical TNTcharge in the range of 0.2–5000 kg,the universality of the prediction model is verified,which can provide a reference for the numerical simulation of underwater explosion shock wave in the two-dimensional near-field range.

关 键 词：水下爆炸 数值仿真 网格尺寸 人工粘性系数 误差预估模型 

分 类 号：TJ630.2[兵器科学与技术—武器系统与运用工程] U674[交通运输工程—船舶及航道工程]