多重接口的弹性-塑性里希特迈尔-梅什科夫不稳定性的数值模拟
Xiangyi Liu1, Fenghui Lin1, Zhiye Zhao1
1Department of Modern Mechanics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Physical review. E
|April 18, 2024
概括
这项研究揭示了铜层厚度和材料强度如何影响里希特迈尔-梅什科夫不稳定性. 较薄的层或较弱的材料可以将变形从稳定模式转变为断裂模式,这是由于更强的反射稀化波引起的.
科学领域:
- 固体机械学 固体机械学
- 多相流动动力学 多相流动力学
- 计算物理学的计算物理.
背景情况:
- 里希特迈尔-梅什科夫不稳定性 (RMI) 是流体和固体动力学的一个关键现象.
- 了解RMI对于从惯性封闭融合到天体物理学等应用至关重要.
- 以前的研究通常集中在单个接口或理想流体模型上.
研究的目的:
- 为了研究一个固体系统中多个接口的弹性-塑性里希特迈尔-梅什科夫不稳定性.
- 为了确定铜层厚度和材料强度对接口变形的影响.
- 在不同的条件下识别和分析不同的变形模式 (稳定和断裂).
主要方法:
- 使用多材料固体力学算法的数值模拟.
- 欧勒的框架模拟冲击冲击在扰乱的固体-真空接口.
- 初始层厚度 (x_{I}) 和铜块屈服应力 (σ_{Y2}) 的系统变化.
主要成果:
- 确定并仔细检查了两个变形模式,稳定和破碎.
- 材料强度 (σ_{Y2}) 或层厚度 (x_{I}) 的下降促进了从稳定模式到断裂模式的过渡.
- 观察到更强的反射稀变波 (RRWs) 驱动过渡到断裂模式.
结论:
- 铜层厚度和材料强度是控制RMI的关键参数.
- 冲击波,稀变波和材料特性之间的相互作用决定了不稳定的演变.
- 有一个最大的重新缩放的尖峰宽度,超出这个宽度后,变形模式转换为破碎.
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