加速的地铁客对咳液滴的扩散的影响
1Institute of Geomatics and Urban Spatial Informatics, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
Scientific reports
|June 19, 2024
概括
公共交通安全至关重要. 这项研究表明,在地铁列车中传播的咳液滴受加速的影响,中型液滴受惯性影响,较小的受空气阻力影响,在火车出口造成的感染风险最高.
科学领域:
- 流体动力学 流体动力学
- 公共卫生 公共卫生
- 交通运输安全运输安全
背景情况:
- 冠状病毒通过液滴传播,引发了人们对像地铁这样拥挤的公共交通工具的担忧.
- 移动的铁路车内的内部空气流可以加速滴水分散.
研究的目的:
- 为了研究加速对地铁火车上咳液滴扩散的影响.
- 用计算流体动力学分析基于大小和身体方向的滴水行为.
主要方法:
- 在ANSYS® Fluent中利用计算流体动力学 (CFD) 与修改的k-ε方程.
- 通过调整惯力力校正,在不同的身体方向下模拟滴滴扩散.
主要成果:
- 滴滴扩散受到火车加速度的显著影响.
- 中型液滴 (50-175微米) 主要受到惯性力的影响.
- 较小的水滴 (3.5-20微米) 主要由空气阻力力控制.
结论:
- 地铁客中的滴滴行为取决于尺寸特定的力量 (惯性与空气阻力).
- 感染的最高风险始终观察到公共交通车辆的出口,无论面部方向如何.
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