Effect of human movement on a patient's exhaled viral particle transmission: A numerical study
WU Jialin1,2, WENG Wenguo1,2, FU Ming3,4
1. Institute of Public Safety Research, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Beijing Key Laboratory of City Integrated Emergency Response Science, Beijing 100084, China; 3. Hefei Institute for Public Safety Research, Tsinghua University, Hefei 230601, China; 4. Anhui Province Key Laboratory of Human Safety, Hefei 230601, China
Abstract:Droplet transmission and aerosol transmission are both possible transmission pathways for many respiratory infections (e.g., COVID-19) and human movements may affect these viral particle transmission pathways. Realistic 3-D human models were used here in a computational fluid dynamics (CFD) study to analyze the effect of human movements on the transmission of virus particles exhaled by a patient. The changes in the airflow, pressure and particle diffusion were compared with experimental data to verify the accuracy of the computations. The results show that when a person passes by a sitting patient in a poorly ventilated room, the wake velocities can reach 1.6~2.0 m/s. The airflow velocity can reach 0.53 m/s at 0.10 m from the moving person, 0.22 m/s at 0.25 m away, and 0.13 m/s at 0.55 m away. The airflow fluctuations can last more than 10 s. Double peak airflow velocities are found near the moving person. The pressure difference of 0.49 Pa caused by the moving person moves the air and the viral particles into the wake of the moving person and slows the nearby droplet deposition. More than 50% of the viral particles are deposited on the moving person's body or spread further. Thus, this study recommends less cross-area movement in epidemic areas and that all people should wear masks and use personalized ventilation equipment.
吴家麟, 翁文国, 付明. 人员移动对患者呼出病毒颗粒传播影响的数值研究[J]. 清华大学学报(自然科学版), 2022, 62(6): 1044-1051.
WU Jialin, WENG Wenguo, FU Ming. Effect of human movement on a patient's exhaled viral particle transmission: A numerical study. Journal of Tsinghua University(Science and Technology), 2022, 62(6): 1044-1051.
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