微塑料在乱的开放通道流中沉速度
Usama Ijaz1, Abul B M Baki1, Weiming Wu1
1Department of Civil and Environmental Engineering, Clarkson University, Potsdam, NY, USA.
The Science of the total environment
|June 26, 2024
概括
微塑料 (MP) 在河流中沉积是复杂的. 这项研究揭示了国会议员.
科学领域:
- 环境科学 环境科学
- 流体动力学 流体动力学
- 环境化学环境化学
背景情况:
- 微塑料 (MP) 的运输和水生系统中的命运至关重要.
- 了解MP在河流中的沉降行为是必不可少的,但人们对其了解甚少.
- 流对MP动态有很大的影响.
研究的目的:
- 研究微塑料在动荡的河流流中的速度滞后.
- 为微塑料颗粒开发一种新的阻力系数公式.
- 分析流和粒子惯性对微塑料沉积的影响.
主要方法:
- 使用开放通道管道进行实验研究.
- 粒子跟踪速度计用于分析微塑料的速度.
- 使用的聚烯,纤维素酸和烯酸微塑料 (1-5毫米).
主要成果:
- 与静水相比,微塑料沉速度从-26%到+16%不等.
- 使用悬挂号码开发了一种新的阻力系数公式.
- 新公式预测速度滞后,平均相对误差为16%.
- 具有高斯托克斯数的粒子是由惯性主导的,而不是流.
结论:
- 微塑料沉积受粒子惯性和流动流的影响.
- 开发的阻力系数公式改善了微塑料的运输建模.
- 这些发现对于预测河流环境中的微塑料命运至关重要.
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