Jia Mengfan, Mei Dan, Li Jiaqian, Liu Zihan, Duan Wenzhu, Hou Shanshan
College of Resources and Environmental Engineering, Wuhan University of Science and Technology, Wuhan, 430081, Hubei, China.
School of Mechanical &Automotive Engineering, South China University of Technology, Guangzhou, 510641, Guangdong, China.
Hyg Environ Health Adv. 2022 Sep;3:100015. doi: 10.1016/j.heha.2022.100015. Epub 2022 Jun 30.
Smart classrooms are a relatively confined public space for college students. SARS-COV-2 and other respiratory viruses have been shown to pose a more significant threat to human health in relatively confined spaces. Using numerical simulation method to simulate the transmission and concentration distribution of virus-carrying droplets in smart classrooms in three different seasons (summer, winter, transitional seasons: spring and autumn). The Realizable k-ε model is used to simulate the airflow pattern in the smart classroom, and the Lagrangian method is used to simulate the transmission of droplets. The transmission process of droplets produced from the teacher standing on the platform and the student sitting on the seat is studied. The influence of three kinds of outdoor temperature on droplet transmission and the body deposition fraction of people in the smart classroom is analyzed. The results show that droplet transmission speed is maximum at the temperature of 5 degrees when the outdoor temperature is 5 °C, 20 °C, and 35 °C respectively. At 10 s, the transmission distance of droplets increases by 9.55% compared with that at 20 °C and 10.31% compared with that at 35 °C. In addition, the body deposition fraction is also affected by the location of the vent, with downwind contact being 6 times more likely than upwind contact. The research results can provide suggestions and measures for epidemic prevention and control in smart classrooms.
智慧教室对大学生来说是一个相对封闭的公共空间。严重急性呼吸综合征冠状病毒2（SARS-CoV-2）和其他呼吸道病毒已被证明在相对封闭的空间中对人类健康构成更大威胁。采用数值模拟方法，模拟三种不同季节（夏季、冬季、过渡季节：春季和秋季）智慧教室中携带病毒飞沫的传播及浓度分布。采用可实现k-ε模型模拟智慧教室中的气流模式，采用拉格朗日方法模拟飞沫传播。研究站在讲台上的教师和坐在座位上的学生产生的飞沫传播过程。分析了三种室外温度对智慧教室中飞沫传播及人员身体沉积分数的影响。结果表明，当室外温度分别为5℃、20℃和35℃时，飞沫传播速度在5℃时最大。在10秒时，飞沫传播距离与20℃时相比增加了9.55%，与35℃时相比增加了10.31%。此外，身体沉积分数也受通风口位置的影响，下风向接触的可能性是上风向接触的6倍。研究结果可为智慧教室的疫情防控提供建议和措施。
