在壁效应的存在下,颗粒沉积在剪切稀释,粘弹性液体中
Jodie Whorton1, Thomas J Jones2, James K Russell3
1Lancaster Environment Centre, Lancaster University, Lancaster, LA1 4YQ, UK. j.whorton@lancaster.ac.uk.
Scientific reports
|February 6, 2025
概括
在非牛顿流体中沉的粒子受墙壁效应的影响,与牛顿流体相比,墙壁效应减少. 一种新的方法使用剪切稀释和粘弹性特性准确预测沉降速度.
科学领域:
- 流体动力学 流体动力学
- 类风病学 类风病学 类风病学
- 粒子运输是指粒子运输的过程.
背景情况:
- 在许多工业过程中,粒子沉积在液体中至关重要.
- 墙壁效应显著影响粒子沉积,特别是在狭窄的几何形状中.
- 了解非牛顿流体对粒子沉积的行为是有限的.
研究的目的:
- 通过实验量化墙壁对剪切稀释和粘弹性流体中颗粒沉积的影响.
- 在非牛顿流体中开发粒子终端沉速度的预测模型.
- 为了研究流体体质学对粒子壁相互作用的影响.
主要方法:
- 在静止切削稀释和粘弹性流体中测试粒子沉积速度的实验测量.
- 对高达0.3.3的球体-管径比率的分析.
- 开发和验证一个修改后的斯托克斯方程,包括流体风学.
主要成果:
- 与牛顿流体相比,非牛顿流体中对粒子沉积的墙壁效应减少.
- 传统的墙壁校正的斯托克斯方程很难预测这些流体的沉速度.
- 一个新的校正因子,考虑到剪切稀释和粘弹性 (通过韦森伯格数),准确地预测实验速度.
结论:
- 在剪切稀释和粘弹性液体中沉的颗粒需要针对类型的修复.
- 拟议的定量方法准确地预测了这些复杂流体的终端沉速度.
- 这项研究为优化涉及非牛顿介质中的粒子运输过程提供了有价值的工具.
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