在强流动的大规模特征中,粒子奇拉性并不重要
G Piumini1, M P A Assen1, D Lohse1,2
1Physics of Fluids Group and Max Planck Center for Complex Fluid Dynamics, Department of Science and Technology, J.M. Burgers Center for Fluid Dynamics, and MESA+ Institute, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands.
概括
沉重的,奇拉的,有限大小的惯性粒子可以通过增加能量或增加散射来增强或削弱流. 粒子性会诱导流体旋转,但随着流强度的增加,这种效应会减弱.
科学领域:
- 流体动力学 流体动力学
- 流研究 流研究
- 带有粒子的流动
背景情况:
- 了解粒子-流体相互作用在各种科学和工程领域至关重要.
- 同质的同otropic 流作为研究复杂流动力学的一个基本模型.
- 在流中惯性粒子的行为显著影响流动特征.
研究的目的:
- 为了研究在流中沉重,性,有限大小的惯性粒子的动态.
- 分析粒子属性 (密度,性,体积分数) 和流量参数 (流强度) 对流动动学的影响.
- 阐明粒子影响流能量和散射的机制.
主要方法:
- 使用了三维直接数值模拟 (DNS).
- 一种沉浸边界方法和复杂的碰撞模型促进了四向合模拟.
- 模拟分析了不同的粒子-流体密度比,流强度和粒子体积分数.
主要成果:
- 自由落下的粒子可以在流中增加能量或增强消散,从而增加或减弱流.
- 粒子奇拉性诱导流体阶段的偏向角速度和净.
- 在较高的流强度下,颗粒度对大规模流体特征的影响变得可以忽略不计,这是由于固相动态的变化造成的.
结论:
- 粒子诱导的能量增加和消散之间的相互作用决定了对流的净效应.
- 奇拉粒子表现出独特的碰撞动态,倾向于纠,与冲动反弹的球形粒子不同.
- 流强度在调节粒子特性 (包括力) 对整体流动行为的影响方面发挥着至关重要的作用.
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