层厚度对通过密度过渡层沉降的粒子反弹的影响
Shuhong Wang1, Jiadong Wang1, Jian Deng1
1Department of Mechanics, Zhejiang University, Hangzhou 310027, People's Republic of China.
Physical review. E
|January 20, 2024
概括
在接口交叉过程中,粒子反弹行为是复杂的. 虽然厚层可以防止反弹,但非常薄层 (L/D=0.5-3.0) 也可以通过浮力和二次脱落机制来抑制反弹.
科学领域:
- 流体动力学 流体动力学
- 粒子运输现象 粒子运输现象
- 多相流的流量是多相的.
背景情况:
- 通过密度接口沉积的球形粒子在各种工业过程中至关重要.
- 以前的理解表明,薄接口可以抑制粒子反弹.
- 过渡层厚度对粒子反弹动态的作用需要进一步研究.
研究的目的:
- 为了数值地研究密度过渡层厚度对球形粒子反弹行为的影响.
- 探索在厚厚和薄薄的接口中反弹抑制背后的机制.
- 挑战对粒子界面相互作用的直观理解.
主要方法:
- 一个球形粒子通过密度过渡层沉降的数值模拟.
- 在中等雷诺兹数 (Re_u = 69259) 的粒子动态分析.
- 变化相对过渡层厚度 (L/D) 的参数研究.
主要成果:
- 对于非常厚的接口 (L/D > 10) 没有观察到反弹现象.
- 对于非常薄的接口 (L/D = 0.53.0) 也发生了反弹抑制.
- 已确定两种用于薄层反弹抑制的机制:快速浮力下降和二次流体脱落.
结论:
- 在密度界面上的粒子反弹行为与过渡层厚度相比是非单调的.
- 薄接口可以通过复杂的流体脱离过程来抑制粒子反弹.
- 这些发现完善了对粒子界面动态的理解,特别是对于薄的过渡层.
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