室内人体行走引起颗粒物再悬浮的试验研究

室内人员活动是室内颗粒物再悬浮的重要因素，研究室内颗粒物再悬浮对评估室内空气质量有重要意义.以南开大学津南校区某公共教室为研究区域，通过现场试验研究了室内地面不同积尘负荷下，人员行走引起的PM_2.5再悬浮浓度及其扩散速率.结果表明:①不同时间间隔内的室内地面总颗粒积尘负荷不同，时间间隔为3、7、15 d时，室内PM_2.5积尘负荷分别为0.11、0.18、0.30 g/m2.②室内地面不同总颗粒积尘负荷下，在室内中心过道处行走时引起的PM_2.5再悬浮浓度约1 min后达到最高值，PM_2.5再悬浮浓度达到最高值的时间与地面不同总颗粒积尘负荷的关系不明显.③随着室内地面总颗粒积尘负荷的增加，人体行走引起的PM_2.5再悬浮浓度也会增加.当室内PM_2.5积尘负荷为0.30 g/m2时，行走路径中游坐姿1.1 m处与站姿呼吸平面1.5 m处的PM_2.5再悬浮浓度平均值分别为3.03、2.68 μg/m3，约是室内PM_2.5积尘负荷为0.18与0.11 g/m2时引起的PM_2.5再悬浮浓度平均值的2~3倍.④利用颗粒物传输模型对PM_2.5再悬浮进行量化分析发现，室内地面不同总颗粒积尘负荷的大小与PM_2.5再悬浮分数无关，PM_2.5再悬浮分数为2.2×10-8；室内PM_2.5积尘负荷为0.11、0.18、0.30 g/m2时，行走引起的再悬浮PM_2.5扩散速率分别为7.62×10-11、1.25×10-10、2.08×10-10 kg/s.研究显示，地面积尘负荷的大小会影响人体行走时颗粒物的扩散速率与室内PM_2.5浓度. 

Experimental Study of Human Walking-Induced Indoor Particle Resuspension

Indoor human activity is an important factor of indoor particulate matter resuspension, and the study of indoor particulate matter resuspension is of great significance to the evaluation of indoor air quality. A public classroom in Jinnan campus of Nankai University was taken as the research area. The resuspension concentration and diffusion rate of the human walking-induced indoor PM_2.5 resuspension under different dust loads of indoor ground were studied by field experiments. The results show that: (1) When the time interval is 3, 7 and 15 days, the indoor PM_2.5 dust load is 0.11, 0.18 and 0.30 g/m2, respectively. (2) The concentration of the human walking-induced indoor PM_2.5 resuspension in the indoor center aisle reaches the maximum value at about 1 min for different dust loads of indoor ground. The relationship between the time when PM_2.5 resuspension concentration reaches the maximum value and the different dust loads on the ground is not obvious. (3) With the increase of indoor dust loads, the concentration of the human walking-induced indoor PM_2.5 resuspension will also increase. When the indoor PM_2.5 dust load was 0.30 g/m2, the average concentration of PM_2.5 resuspension for breathing plane at 1.1 m sitting position and 1.5 m standing position was 3.03 and 2.68 μg/m3, respectively, which was about 2-3 times of the average concentration of PM_2.5 resuspension for PM_2.5 dust loads of 0.18 and 0.11 g/m2. (4) The quantitative analysis of PM_2.5 resuspension by using particle transport model shows that the magnitude of dust loads don't affect the resuspension fraction of PM_2.5, and the resuspension fraction of PM_2.5 is 2.2×10-8. When the indoor PM_2.5 dust loads is 0.11, 0.18, 0.30 g/m2, the diffusion rate of the human walking-induced indoor PM_2.5 resuspension is 7.62×10-11, 1.25×10-10 and 2.08×10-10 kg/s, respectively. The dust load on the ground will affect the diffusion rate of particulate matter and indoor PM_2.5 concentration.