悬浮物的粘度对称挤压流
K Zidi1, B Darbois Texier1, G Gauthier1
1Université Paris-Saclay, CNRS, Laboratoire FAST, 91405, Orsay, France.
The European physical journal. E, Soft matter
|March 1, 2024
概括
这项研究探讨了使用压力测量在挤压流中的粒子悬浮质学. 结果与马龙-皮尔斯定律一致,验证了大间隙悬浮的粘度确定.
科学领域:
- 流体动力学 流体动力学
- 材料科学 材料科学 材料科学
- 类风病学 类风病学 类风病学
背景情况:
- 微粒悬浮的风学在简单的剪流中得到了很好的研究.
- 其他流量配置,如挤压流,在实践中是相关的,但较少探索.
- 了解各种流量中的悬浮行为对于工业应用至关重要.
研究的目的:
- 为了研究压缩流配置中的颗粒悬浮的气质学.
- 使用局部压力测量来推断有效粘度.
- 为了验证在挤压流程中确立的风学规律的适用性.
主要方法:
- 使用移动的磁盘在低雷诺兹数下接近固定墙壁来产生挤压流.
- 测量墙壁压力场的演变.
- 从辐射压力下降中推断有效粘度.
- 用牛顿流体验证实验设置.
主要成果:
- 对不同的挤压速度和粒子体积分数进行了有效粘度测量.
- 实验结果表明与马龙-皮尔斯定律一致,通常在简单的剪切流中观察到.
- 粘度测定方法在较大的间隙宽度上得到了验证.
结论:
- 使用局部压力进行挤压流体病理学测量是有效的粒子悬浮的特征.
- 马龙-皮尔斯定律适用于挤压流中的颗粒悬浮.
- 这种技术使得大空隙中大颗粒悬浮的研究成为可能,克服了诸如Couette流电池等传统方法的局限性.
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