室外颗粒物通过缝隙进入室内的渗透特性研究

发布时间：2018-05-19 11:57

本文选题：颗粒物 + 穿透率　；参考：《北方工业大学》2016年硕士论文

【摘要】：雾霾中含有的PM2.5颗粒可以比较容易地通过呼吸系统进入肺部,并经过肺泡渗透进入血液,因此对人体健康会产生很大影响。而室内空气中PM2.5颗粒的主要来源是通过门、窗、墙体的缝隙渗透进入室内的空气所含的污染物。因此研究室外空气所含污染物进入室内的渗透规律具有重要意义。本文针对污染物通过缝隙渗透的过程,首先在实验方面对其渗透性能进行了测试,其次应用理论方法对污染物渗透进入室内的主要影响因素进行了分析,最后根据上述研究成果应用数值模拟的方法对实际污染物渗透进入室内的渗透量进行了计算。本文的研究内容及结果如下：(1)本文搭建了测试颗粒物渗透特性的实验台,并研究了压差、缝隙高度、缝隙内表面粗糙度以及颗粒物粒径等四个因素对穿透率的影响规律。实验时颗粒物浓度控制在150～30mμg/m3之间,粗糙度控制在0～20.5μm,压差控制在4～10Pa,缝隙高度控制在0.3～1mm。实验结果表明,颗粒物渗透率的大小集中于0.55～1之间。(2)数据分析表明颗粒物粒径的大小对穿透率的实验偏差有影响。颗粒物粒径变大时,实验偏差也随之变大。渗透率与压差呈线性正比,即渗透率随着压差变大而变大,两者间相关系数r一般大于0.7。除此之外,渗透率与粒径的大小呈反比,即随着粒径增大穿透率变小。与压差和粒径相比,缝隙高度和表面粗糙度对渗透率的影响相对较小。(3)根据改变单一变量的方法来推导室内外浓度变化的关系,得到室内外浓度平衡时间的计算公式以及推算室内颗粒物最小净化风量的计算公式。基于上述研究成果,本文应用数值模拟的方法,分析了颗粒物通过门窗缝隙进入室内的渗透量。模拟时考虑了四种工况,分别为：低风速、中等雾霾工况,低风速、低雾霾工况,中等风速、中等雾霾工况和高风速、高雾霾工况。研究结果表明：室外颗粒物的浓度对室内污染物浓度增长的速度起主要作用。通过计算可知,当室外出现雾霾时,室内颗粒物浓度在2-3小时内与室外浓度达到平衡,即室内颗粒物浓度变化存在延时效应。
[Abstract]:The PM2.5 particles contained in haze can easily enter the lungs through the respiratory system and infiltrate into the blood through the alveoli, which will have a great impact on human health. However, the main source of PM2.5 particles in indoor air is the pollutants contained in the air through the cracks of doors, windows and walls. Therefore, it is of great significance to study the permeation law of indoor pollutants in outdoor air. In this paper, the permeation performance of pollutants through the gap is tested in the experiment, and the main factors influencing the permeation of pollutants into the room are analyzed by using the theory and method. Finally, based on the above research results, the infiltration amount of actual pollutants into the room is calculated by numerical simulation method. The main contents and results of this paper are as follows: (1) in this paper, an experimental bench is set up to test the permeability of particulate matter, and the influence of four factors, such as pressure difference, gap height, inner surface roughness and particle size, on the penetration rate is studied. In the experiment, the concentration of particulate matter was controlled in the range of 150 ~ 30m 渭 g/m3, the roughness was controlled at 0 ~ 20.5 渭 m, the pressure difference was controlled at 4 ~ 10 Pa, and the height of the gap was controlled at 0.3 ~ (-1) mm. The experimental results show that the particle permeability is concentrated in the range of 0.55 ~ (-1). The data analysis shows that the particle size has an effect on the experimental deviation of the penetration rate. When the particle size becomes larger, the experimental deviation also increases. The permeability is proportional to the pressure difference, that is, the permeability increases with the pressure difference, and the correlation coefficient r between them is generally greater than 0.7. In addition, the permeability is inversely proportional to the particle size, that is, the penetration becomes smaller with the increase of the particle size. Compared with pressure difference and particle size, the effect of gap height and surface roughness on permeability is relatively small. The formula for calculating the equilibrium time of indoor and outdoor concentration and the formula for calculating the minimum purifying air volume of indoor particulate matter were obtained. Based on the above research results, the permeation of particulate matter through the gap between doors and windows was analyzed by numerical simulation. Four conditions were considered in the simulation, namely: low wind speed, medium haze condition, low wind speed, low haze condition, moderate wind speed, moderate haze condition, high wind speed and high haze condition. The results show that the concentration of outdoor particles plays a major role in the growth rate of indoor pollutant concentration. The results showed that when haze appeared outside, the indoor particulate concentration was balanced with outdoor concentration within 2-3 hours, that is, the change of indoor particulate concentration had a delay effect.
【学位授予单位】：北方工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TU834.8

【相似文献】