关于渗透通风条件下室内PM2.5净化过滤负荷计算相关设计参数探讨

Determination on the Calculation and Key Design Parameters of Indoor PM2.5 Filtration Load Under the Condition of Building Infiltration

大量实测结果表明,即使关闭建筑外窗,室外细颗粒物(即PM2.5)仍可跟随建筑外窗缝隙渗透通风进入室内,污染室内环境。合理评估室内PM2.5净化过滤负荷对空气净化器设计选型有重要指导意义。研究团队前期提出了基于渗透通风条件下室内PM2.5净化过滤负荷计算模型,然而,模型中房间换气次数和细颗粒物穿透系数难以简单确定,尚未给出推荐设计值,限制了模型的工程应用价值。为此,本文结合研究团队前期提出的房间换气次数、PM2.5穿透系数与沉降率推算模型,以及北京地区多个办公建筑室内外PM2.5质量浓度和室外气象参数长期监测结果,研究并提出了基于渗透通风条件下,不同气密性等级建筑外窗对应的单位缝长渗透通风量和穿透系数确定方法,给出了推荐设计值,评估了建筑外窗气密性等级对空气净化器净化寿命的影响。

Field measurement results reveal outdoor PM2.5 can still go indoors through building infiltration even all the windows and doors are closed.An accurate evaluation of indoor PM2.5 filtration load will provide great help on designing an efficient indoor air filtration device.A calculation model of indoor PM2.5 filtration load has been proposed by the authors in previous studies.However,in this model,some important parameters,such as air change rate and particle penetration factor,are too complex to obtain and the recommend design values for engineering application were not proposed.Therefore,a determination method of the two parameters was proposed in this study,based on the relevant parameters’calculation models developed by the authors previously and the long-term field measurement database of indoor-outdoor PM2.5 mass concentrations and outdoor meteorological parameters in Beijing,China.The recommend design values of the two parameters under various external window air-tightness levels were provided.Additionally,the influence of the external window air-tightness level on cleaning life span of air filters were evaluated.