新风量对地铁客室咳嗽飞沫传播影响的数值模拟研究  

Numerical simulation of effect of fresh air rates on transmission of cough droplet transmission in subway passenger cabin

作　　者：李恒奎 伍钒 梁习锋[1,3,4] 董航 李旋 LI Hengkui;WU Fan;LIANG Xifeng;DONG Hang;LI Xuan(Key Laboratory of Traffic Safety on Track,Ministry of Education,School of Traffic&Transportation Engineering,Central South University,Changsha 410075,China;CRRC Qingdao Sifang Co.Ltd.,Qingdao 266109,China;Joint International Research Laboratory of Key Technologies for Rail Traffic Safety,Central South University,Changsha 410075,China;National&Local Joint Engineering Research Center of Safety Technology for Rail Vehicle,Central South University,Changsha 410075,China)

机构地区：[1]中南大学交通运输工程学院,轨道交通安全教育部重点实验室,湖南长沙410075 [2]中车青岛四方机车车辆股份有限公司,山东青岛266109 [3]中南大学轨道交通安全关键技术国际合作联合实验室,湖南长沙410075 [4]中南大学轨道交通列车安全保障技术国家地方联合工程研究中心,湖南长沙410075

出　　处：《中南大学学报（自然科学版）》2024年第5期1691-1701,共11页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金面上资助项目(52072413);国家自然科学基金委员会−中国国家铁路集团有限公司铁路基础研究联合基金资助项目(U2368213)。

摘　　要：优化通风系统参数以降低乘客呼吸道传染病的感染风险是创造安全、舒适的地铁客室出行环境的重要途径。利用欧拉−拉格朗日数值模拟方法对地铁客室中呼吸道飞沫传播进行模拟,研究不同送风量下乘客咳嗽释放的飞沫扩散规律和时空分布特性。研究结果表明:随着新风量增加,车厢通风系统对飞沫粒子的清除速度和效率也相应提高;当新风量为2000 m3/h时,仅有3.9%的飞沫在30 s内进入废排口;而当新风量为8000 m3/h时,在10 s内38.9%的粒子进入废排口;车厢内悬浮的粒子数量并非呈线性下降,而是随新风量的增加呈现复杂的变化;随着新风量提高,车厢内主导飞沫运动的气流逐渐由回风产生的气流转变为废排口产生的气流,同时,废排口气流在车厢内形成的涡流区域逐渐增大,导致部分未能快速进入废排口的部分飞沫在车厢内的悬浮时间延长;废排口附近乘客摄入粒子的比例随着新风量的增加表现出显著的差异;随着新风量的增加,在感染乘客同侧区域的乘客被感染风险逐渐减小,而在感染乘客面对区域的乘客被感染风险随着新风量的增加先增加后减小。研究结果可为制定预防地铁客室内呼吸道传染病毒空气传播的控制策略提供参考。Optimizing ventilation system parameters to reduce the risk of respiratory infectious diseases among passengers is crucial for creating a safe and comfortable travel environment in subway carriages.The Euler−Lagrange numerical simulation method was used to simulate the spread of respiratory droplets in subway carriages focused on the diffusion patterns and spatiotemporal distribution characteristics of passenger cough-generated droplets at different air supply rates.The results show that the carriage ventilation system's effectiveness in clearing droplets increases with the increase of the fresh air rate.For a fresh air volume of 2000 m3/h,only 3.9%of droplets enter the exhaust outlets within 30 s,while at a fresh air volume of 8000 m3/h,38.9%of particles can be expelled by the exhaust outlets within 10 s.The proportion of suspended particles inside the carriage does not linearly decrease with the increase of the fresh air volume but exhibits a complex variation.As the fresh air volume increases,the dominant airflow for droplet movement within the carriage shifts from the return air to the exhaust outlet-generated airflow.Simultaneously,the vortex region created by the exhaust outlet-generated airflow gradually enlarges,prolonging the suspension time of droplets that fail to enter the exhaust outlet quickly.The proportion of inhaled particles by passengers near the exhaust outlets demonstrates significant differences with the increase of the fresh air rate.In the infected passenger side,the infection risk for passengers gradually decreases with the increase of the fresh air rate.In the region facing an infected passenger,the infection risk for nearby passengers initially increases and then decreases with the increase of the fresh air rate.The results can provide reference for formulating strategies to prevent airborne transmission of respiratory viruses in subway carriages.

关 键 词：地铁列车 新风量 咳嗽 飞沫 数值模拟 

分 类 号：U264.0[机械工程—车辆工程]