Liu Sumei, Koupriyanov Mike, Paskaruk Dale, Fediuk Graham, Chen Qingyan
Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
Price Industries Limited, 638 Raleigh Street Winnipeg, MB R2K 3Z9, Canada.
Sustain Cities Soc. 2022 Apr;79:103718. doi: 10.1016/j.scs.2022.103718. Epub 2022 Jan 29.
Effective ventilation could reduce COVID-19 infection in buildings. By using a computational fluid dynamics technique and advanced experimental measurement methods, this investigation studied the air velocity, air temperature, and particle number concentration in an office under a mixing ventilation (MV) system and a displacement ventilation (DV) system with different ventilation rates. The results show reasonably good agreement between the computed results and measured data. The air temperature and particle number concentration under the MV system were uniform, while the DV system generated a vertical stratification of the air temperature and particle number concentration. Because of the vertical stratification of the particle number concentration, the DV system provided better indoor air quality than the MV system. An increase in ventilation rate can reduce the particle concentration under the two systems. However, the improvement was not proportional to the ventilation rate. The increase in ventilation rate from 2 ACH to 4 ACH and 6 ACH for MV system reduced the particle concentration by 20% and 60%, respectively. While for the DV system, increasing the ventilation rate from 2 ACH to 4 ACH and 6 ACH reduced the particle concentration by only 10% and 40%, respectively. The ventilation effectiveness of the MV system was close to 1.0, but it was much higher for the DV system. Therefore, the DV system was better than the MV system.
有效的通风可以减少建筑物内的新冠病毒感染。通过使用计算流体动力学技术和先进的实验测量方法，本研究考察了在不同通风率下混合通风（MV）系统和置换通风（DV）系统中办公室内的空气流速、空气温度和粒子数浓度。结果表明计算结果与测量数据之间具有较好的一致性。MV系统下的空气温度和粒子数浓度较为均匀，而DV系统则产生了空气温度和粒子数浓度的垂直分层。由于粒子数浓度的垂直分层，DV系统提供了比MV系统更好的室内空气质量。通风率的增加可以降低两种系统下的粒子浓度。然而，这种改善与通风率不成正比。MV系统的通风率从2次换气次数（ACH）增加到4 ACH和6 ACH时，粒子浓度分别降低了20%和60%。而对于DV系统，通风率从2 ACH增加到4 ACH和6 ACH时，粒子浓度仅分别降低了10%和40%。MV系统的通风效率接近1.0，但DV系统的通风效率要高得多。因此，DV系统优于MV系统。
