全空气一次回风系统室内PM_(2.5)浓度衰减的影响因素研究

Factors Influencing Attenuation of Indoor PM_(2.5) for Primary Return All-air System

人们绝大多数时间都在室内度过,室内颗粒物浓度对人体健康有重要影响。本文依据质量守恒定律建立室内颗粒物的动态平衡方程,探讨其衰减的影响因素。对于全空气一次回风集中过滤的系统,室内PM_(2.5)浓度的衰减时间仅与回风换气次数、新风换气次数和过滤效率有关;使用蚊香作为内尘源(产尘量为11.77+1.33 mg/h),通过实验在30 m^3环境舱内,验证了该模型在无内尘源和有内尘源条件下的准确性。对于换气次数N>8,新风比S>0.1,过滤器PM_(2.5)效率η>70%的一次回风全空气系统,室内PM_(2.5)浓度衰减达到稳定的时间约为0.5 h。

People spend most of their time indoors and the concentration of indoor particulates can influence the peoples＇ health greatly. A dynamic model was developed to analyze the factors that influence the attenuation of indoor particulates. For all-air primary air system,the attenuation time is only related to the filter efficiency and ventilation rate of fresh air and return air. Mosquito-repellent incense is used as the inner source of PM2.5,which can produce PM2.5 at the rate of 11. 77 ＋ 1. 33 mg/h. Experiments were carried out to verify the dynamic model in an environmental chamber with and without the inner source of PM2.5. It takes about half an hour to reach the balance state for primary return all-air system with air change times N 8,fresh air ration S 0. 1 and PM2.5 efficiency η 70%.