混凝土中爆炸模拟的数值方法比较

Comparison study of numerical methods in simulation of explosion in concretes

应用AUTODYN商业软件对装药在混凝土靶介质中的爆炸过程进行数值模拟,对比了混凝土中爆炸模拟的不同方法。将各数值方法模拟得到的混凝土毁伤特征尺寸与相关实验数据进行比较,研究了各数值方法的准确性及描述混凝土毁伤特征的可靠性参数。结果发现:Euler算法计算的压力最大,SPH和Lagrange耦合算法计算的压力最小;Euler算法和SPH算法计算的压力衰减过程会发生比较显著的扰动。以不同的平均网格尺寸对数值模拟结果的影响分析了各种数值方法的稳定性。比较靶体上同一测点的压力时间历程表明网格变化对测点处压力影响不大。通过应用各种数值方法模拟再现混凝土中的爆炸过程,揭示了各种方法的优缺点,明确了现有商业软件模拟混凝土中爆炸的适用性。

Different numerical methods have been implemented to simulate the explosion in concretes by the AUTODYN commercial software.To verify the accuracy of numerical methods,the characteristic damage dimensions of concretes which obtained by numerical methods are used to compare with the results got by experiments.The credible parameters which can be used to represent the practical explosion damage of concretes in numerical methods are studied.Different mesh sizes are used in simulation to study the stability of numerical methods and their effects on numerical results.The pressure-time history of the same point in the concrete targets got by different numerical methods is investigated.Numerical results show that the process of explosion in concretes can be reproduced by the numerical methods adopted in this research.The advantages and weaknesses of different numerical methods are revealed.Finally,the applicability of different numerical methods in simulating the explosion in concretes determined.