An experiment and numerical study of resuspension of fungal spore particles from HVAC ducts
An experiment and numerical study of resuspension of fungal spore particles from HVAC ducts
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HVAC 管道中真菌孢子颗粒再悬浮的实验和数值研究
DOI：
10.1016/j.scitotenv.2019.134742
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发表时间：
2020
影响因子：
9.8
通讯作者：
Deng Qihong
中科院分区：
文献类型：
--
作者：
Liu Zhijian;Niu Haotian;Rong Rui;Cao Guoqing;He Bao-Jie;Deng Qihong
真菌孢子在暖通空调管道表面的再悬浮是造成室内生物污染的重要因素之一。为了有效地控制室内生物气溶胶污染，了解空调管道中真菌孢子的再悬浮特性是非常必要的。因此，本研究旨在探讨粒子的运动行为，并进一步探讨粒子再悬浮随暖通空调运行模式的变化。本文在实验和数值研究的基础上，具体研究了颗粒的微观运动行为和颗粒尺寸的影响（1、4、7和10 μm），空气温度（9、15和30 °C），相对湿度（20、50和80%），管道表面粗糙度（0.5和50 μm）和空气流速（0.3，0.9，1.5和2.5 m/s）对水平HVAC管道中颗粒短期再悬浮的影响。结果表明，孢子颗粒主要是滚动而不是滑动或被提升到空气中。与大颗粒相比，小颗粒对壁面粗糙度的敏感性更高。孢子的再悬浮率主要受气流速度和颗粒大小的影响，当气流速度在0.9 ~ 2.5m/s范围内增加时，颗粒的再悬浮率可增加6倍。相比之下，空气温度或相对湿度对颗粒物再悬浮率的影响可以忽略不计。总之，本研究为暖通空调管道真菌孢子再悬浮提供了理论依据，为有效控制室内生物污染奠定了基础。
Fungal spore resuspension on the surfaces of the heating, ventilation and air-conditioning (HVAC) ducts have been verified as one of the most important factors causing indoor biological pollution. To effectively control indoor bioaerosols pollution, it is essential to understand the resuspension characteristics of fungal spores in HVAC ducts. Therefore, this study aims to investigate the movement behavior of particles and further the variation of particle resuspension with HVAC operation mode. Based on the experimental and numerical study, this study specifically investigated the micro-movement behavior of particles and impact of particle size (1, 4, 7 and 10 μm), air temperature (9, 15 and 30 °C), relative humidity (20, 50 and 80%), duct surface roughness (0.5 and 50 μm) and air velocity (0.3, 0.9, 1.5 and 2.5 m/s) on the short-term resuspension of particle in horizontal HVAC ducts. Results indicate that spore particles were dominantly rolling off rather than sliding or being lifted into the air. Compared with larger particles, smaller ones were more sensitive to the wall roughness. The resuspension rate of spores was mainly affected by airflow velocity and particle size, where the resuspension rate of particles increased by up to six times with the increase of airflow velocity from 0.9 to 2.5 m/s. In comparison, either air temperature or relative humidity made negligible difference to particle resuspension rate. Overall, this study provides the knowledge of fungal spore resuspension in HVAC ducts, laying the foundation for effectively controlling the indoor biological pollution.