Shock-induced damage and dynamic fracture in cylindrical bodies submerged in liquid
Shock-induced damage and dynamic fracture in cylindrical bodies submerged in liquid
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DOI：
10.1016/j.ijsolstr.2019.04.002
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发表时间：
2019-09-01
影响因子：
3.6
通讯作者：
Wang, Kevin G.
中科院分区：
文献类型：
--
作者：
Cao, Shunxiang;Zhang, Ying;Wang, Kevin G.
了解固体材料对冲击载荷的响应对于减轻冲击引起的损伤和故障以及推进冲击波在材料改性中的有益使用是重要的。在本文中，我们考虑一个代表性的脆性材料，BegoStone，在圆柱体的形式和淹没在水中。我们提出了一个计算研究之间的因果关系，规定的冲击载荷和由此产生的弹性波和固体材料的损伤。一个最近开发的三维计算框架，FIVER，采用耦合有限体积可压缩流体求解器与有限元结构动力学求解器，通过建设和解决当地的，一维流固黎曼问题。采用连续介质损伤力学模型和单元腐蚀法对材料损伤和断裂进行了建模和仿真。在冲击波碎石术的背景下，计算模型进行了验证，并与实验数据的结果进行了比较。我们首先表明，在校准微观损伤的增长率和宏观断裂的阈值后，计算框架能够捕获在实验室实验中观察到的冲击诱导断裂的位置和形状。接下来，我们介绍了一个新的冲击波的唯象模型，并提出了一个数值参数的研究，在一个单一的冲击载荷的影响，其中冲击波的波形，幅度和大小的目标材料是不同的。特别是，我们改变波形逐渐从一个具有非单调衰减与拉伸阶段的一个表现出单调衰减没有拉伸阶段。结果表明，当冲击脉冲的长度与靶材料的长度相当时，即使两者具有相同的幅度、持续时间和声能，前者的波形也可能比后者引起更显著的损伤。(C)2019由Elsevier Ltd.出版
Understanding the response of solid materials to shock loading is important for mitigating shock-induced damages and failures, as well as advancing the beneficial use of shock waves for material modifications. In this paper, we consider a representative brittle material, BegoStone, in the form of cylindrical bodies and submerged in water. We present a computational study on the causal relationship between the prescribed shock load and the resulting elastic waves and damage in the solid material. A recently developed three-dimensional computational framework, FIVER, is employed, which couples a finite volume compressible fluid solver with a finite element structural dynamics solver through the construction and solution of local, one-dimensional fluid-solid Riemann problems. The material damage and fracture are modeled and simulated using a continuum damage mechanics model and an element erosion method. The computational model is validated in the context of shock wave lithotripsy and the results are compared with experimental data. We first show that after calibrating the growth rate of microscopic damage and the threshold for macroscopic fracture, the computational framework is capable of capturing the location and shape of the shock-induced fracture observed in a laboratory experiment. Next, we introduce a new phenomenological model of shock waveform, and present a numerical parametric study on the effects of a single shock load, in which the shock waveform, magnitude, and the size of the target material are varied. In particular, we vary the waveform gradually from one that features non-monotonic decay with a tensile phase to one that exhibits monotonic decay without a tensile phase. The result suggests that when the length of the shock pulse is comparable to that of the target material, the former waveform may induce much more significant damage than the latter one, even if the two share the same magnitude, duration, and acoustic energy. (C) 2019 Published by Elsevier Ltd.