扩展动力学理论应用于压力控制的切割流,在刚性,的平面之间,无摩擦球体的切割流
Dalila Vescovi1, Astrid S de Wijn2, Graham L W Cross3
1Politecnico di Milano, 20133 Milano, Italy. dalila.vescovi@polimi.it.
Soft matter
|October 24, 2024
概括
这项研究使用离散元素模拟来模拟凸起平面之间的颗粒气体流. 结果验证了运动理论,并预测了在特定负载下结晶,这对于了解颗粒物质至关重要.
科学领域:
- 物理 物理学 物理
- 机械工程 机械工程
- 材料科学 材料科学 材料科学
背景情况:
- 颗粒状材料在剪切下表现出复杂的流动行为.
- 动力学理论为理解颗粒气体动力学提供了一个框架.
- 以前的模型往往简化了边界条件和粒子相互作用.
研究的目的:
- 在的平面之间数量地研究相同的,无摩擦球体的稳定流动.
- 验证和扩展现有的颗粒气体运动理论.
- 分析各种参数对流量属性的影响,并预测相位过渡.
主要方法:
- 使用离散元件模拟 (DEM) 来建模粒子流.
- 测量了关键水力动力学场的空间分布.
- 一个基于扩展的动力学理论的微分方程系统被整合.
主要成果:
- DEM模拟证实了来自不弹性运动理论的状态方程和粘度的预测.
- 扩展动力学理论的构成关系,包括速度相关性,已成功测试.
- 分析了流量形状,应力压力比率和间隙变化,涉及恢复,负载和凸起.
结论:
- 这项研究表明,DEM模拟与扩展动力学理论之间有着显著的一致性.
- 根据边界体积分数预测了结晶的临界负荷,与模拟一致.
- 这些发现提供了对颗粒物质行为和相位过渡的见解.
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