A multi-physics methodology for the simulation of reactive flow and elastoplastic structural response
A multi-physics methodology for the simulation of reactive flow and elastoplastic structural response
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DOI：
10.1016/j.jcp.2018.03.037
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发表时间：
2017-10
期刊：
影响因子：
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通讯作者：
L. Michael;N. Nikiforakis
中科院分区：
文献类型：
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作者：
L. Michael;N. Nikiforakis
我们提出了一种数值模拟的不同的，相互作用的物理过程描述的组合的可压缩，惰性和反应形式的欧拉方程，多相方程和弹塑性方程的数值方法。这些方程组通常通过耦合有限元和CFD模型来求解。在这里，我们同时解决他们，通过重铸所有的方程在同一个，双曲型，并解决他们在同一个网格上使用相同的有限体积数值格式。所提出的可压缩，多相，流体动力学配方可以采用五个反应和非反应流模型的层次结构，这使得简单到更复杂的应用程序直接描述的适当的选择。流体动力学和弹塑性系统之间的通信是通过混合材料的黎曼解算器在系统的边界，这代表物理材料的边界。为此，我们推导出近似的混合黎曼解的特征方程的基础上，上述模型的每一对。反应流和弹塑性实体建模的组件分别进行验证，然后才提出完整的，耦合系统的验证。多维用例证明了反应流-固体相互作用方法在汽车（例如汽车碰撞）或防御（例如爆炸反应装甲）应用中由于剧烈反应而导致的反应流和结构响应的冲击驱动引发的背景下的适用性。考虑了气态、液态和固态的几种爆炸物（C4、爆炸物、硝基甲烷、气体燃料）。
We propose a numerical methodology for the numerical simulation of distinct, interacting physical processes described by a combination of compressible, inert and reactive forms of the Euler equations, multiphase equations and elastoplastic equations. These systems of equations are usually solved by coupling finite element and CFD models. Here we solve them simultaneously, by recasting all the equations in the same, hyperbolic form and solving them on the same grid with the same finite-volume numerical schemes. The proposed compressible, multiphase, hydrodynamic formulation can employ a hierarchy of five reactive and non-reactive flow models, which allows simple to more involved applications to be directly described by the appropriate selection. The communication between the hydrodynamic and elastoplastic systems is facilitated by means of mixed-material Riemann solvers at the boundaries of the systems, which represent physical material boundaries. To this end we derive approximate mixed Riemann solvers for each pair of the above models based on characteristic equations. The components for reactive flow and elastoplastic solid modelling are validated separately before presenting validation for the full, coupled systems. Multi-dimensional use cases demonstrate the suitability of the reactive flow-solid interaction methodology in the context of impact-driven initiation of reactive flow and structural response due to violent reaction in automotive (e.g. car crash) or defence (e.g. explosive reactive armour) applications. Several types of explosives (C4, Detasheet, nitromethane, gaseous fuel) in gaseous, liquid and solid state are considered.