三维准静态颗粒流的短暂应力和织物模型
1Department of Mechanical Engineering, University of Antofagasta, Antofagasta, Chile. eduardo.rojas@uantof.cl.
Soft matter
|March 26, 2025
概括
我们开发了一个用于密集颗粒流的3D连续模型,通过塑料建模连接颗粒材料和金属. 该模型准确地预测了剪切过程中的织物和应力演变,通过离散元素方法模拟验证.
科学领域:
- 连续性力学是连续性的.
- 颗粒物理 颗粒物理
- 计算建模计算建模
背景情况:
- 密集的颗粒流在剪切下表现出复杂的行为.
- 现有的模型往往难以捕捉短暂的反应和结构演变.
- 在金属中取得成功的塑料硬化理论为颗粒型介质提供了潜在的框架.
研究的目的:
- 提出和验证一个一般的3D连续模型,用于预测密集颗粒流中的合织物和应力瞬态.
- 使用统一的塑料建模框架,建立颗粒流和金属可塑性之间的联系.
- 研究颗粒状介质背压的起源及其与金属系统的区别.
主要方法:
- 基于同位素和动力硬化理论开发了一个3D连续模型.
- 在织物张量演化方程中纳入了"接触持久性"参数.
- 模拟的剪切应力使用背应力 (织物张力比例) 和剪切率术语,通过3D Couette细胞模拟的离散元件方法 (DEM) 数据进行验证.
主要成果:
- 该模型准确地预测了3D密集颗粒流中的织物和偏离应力张量的演变.
- 在模型预测和DEM模拟之间,对于各种剪切方向变化,达成了良好的协议.
- 该模型在热力学上是一致的,与金属相比,在颗粒状介质中揭示了背压的不同来源.
结论:
- 拟议的3D连续模型为模拟密集颗粒流中的短暂反应提供了一个强大的框架.
- "接触持久性"的概念有效地捕捉了不同剪切条件下的织物网络行为.
- 颗粒状介质中的背应力源于扩张性对织物对齐和流速的依赖,而不是存储的缺陷能量.
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