Mechanical Engineering Department, American University of Beirut, Beirut, Lebanon.
Human-Oriented Built Environment Lab, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
Indoor Air. 2021 Sep;31(5):1377-1390. doi: 10.1111/ina.12840. Epub 2021 Apr 24.
Particle release from human skin and clothing has been identified as an important contributor to particulate matter burden indoors. However, knowledge about modeling the coarse particle release from skin and clothing is limited. This study developed a new empirically validated CFD modeling methodology for particle release and transport from seated occupants in an office setting. We tested three modeling approaches for particle emissions: Uniform; Uniform + Localized; and Uniform + Localized with Body Motion; applied to four office scenarios involving a single occupant and two occupants facing each other at 1- and 2-m distances. Uniform particle emissions from skin and clothing underpredicted personal inhalation exposure by as much as 55%-80%. Combining uniform with localized emissions from the armpits drastically reduced the error margin to <10%. However, this modeling approach heavily underestimated particle mass exchange (cross-contamination) between the occupants. Accounting for the occupant's body motion-by applying the momentum theory method-yielded the most accurate personal exposure and cross-contamination results, with errors below 12%. The study suggests that for accurate modeling of particle release and transport from seated occupants indoors, localized body emissions in combination with simplified bodily movements need to be taken into account.
人体皮肤和衣物的颗粒物释放已被确定为室内颗粒物负荷的一个重要贡献因素。然而，关于从皮肤和衣物释放粗颗粒物的建模知识有限。本研究开发了一种新的经验验证的 CFD 建模方法，用于模拟办公环境中坐姿人员的颗粒物释放和传输。我们测试了三种颗粒物排放的建模方法：均匀排放、均匀排放+局部排放，以及均匀排放+局部排放加人体运动，应用于涉及单个和面对面坐在 1 米和 2 米距离的两个人员的四个办公场景。皮肤和衣物的均匀颗粒物排放对个人吸入暴露的预测低了 55%至 80%。将均匀排放与腋窝局部排放相结合，可将误差幅度降低到<10%。然而，这种建模方法严重低估了人员之间的颗粒物质量交换（交叉污染）。通过应用动量理论方法考虑人员的身体运动，可获得最准确的个人暴露和交叉污染结果，误差低于 12%。本研究表明，要准确模拟室内坐姿人员的颗粒物释放和传输，需要考虑局部身体排放和简化的身体运动。
