【作者】 周怀改；

【导师】 刘方；

【作者基本信息】 重庆大学 ， 供热、供燃气、通风及空调工程， 2007， 硕士

【摘要】 随着社会经济的发展,越来越多的建筑经过了大量的装饰、装修,而且由于建筑节能的需要,房间的密闭性加强,这样就造成了室内存在大量低浓度挥发性有机物,它们将会对人体产生严重危害。研究通风对室内污染物浓度分布的影响是建筑环境研究中的重要工作之一,研究成果对于完善室内空气品质的评价体系,优化建筑室内通风系统的设计以及尽早将室内空气品质的研究体现在工程设计上等都有十分重要的意义。本文介绍了室内空气品质、通风效率、通风方式等。综述了室内空气品质以及CFD技术研究现状和存在问题。采用数值模拟与实验验证相结合的研究方法,以计算流体力学软件PHOENICS为模拟仿真工具,通过多次模拟选定合理的描述污染物分布的数学模型,并对污染源进行合理的设置。通过实测教学楼空调房间甲醛的浓度分布,验证了模拟程序设置的正确性。以重庆江津白沙镇建筑节能示范楼为研究对象,探讨了住宅建筑中自然通风与机械通风对污染物浓度分布的影响,并讨论了自然通风中,风口位置与风口大小对室内污染物浓度分布的影响,讨论了机械通风中,换气次数、风速以及进风口位置对污染物浓度分布的影响。自然通风实验结果表明,示范楼建筑设计的自然通风方案,可以有效排出室内污染物;现场测试结果显示,简单装修的房间,室内HCHO和TVOC的浓度都满足室内空气质量标准的要求,说明该示范楼设计的自然通风方案是合理的。机械通风实验结果表明,三种机械通风量对室内污染物浓度分布影响不大。最大风量所排出室内污染物的速率较小。自然通风数值模拟结果表明,风口位置和风口大小都会影响室内污染物的浓度分布。东、西外窗同时开启,易于形成穿堂风,能够有效排出室内污染物;增大进风口面积,风量增大,排出室内污染物的能力增强;秋季在风压和热压作用下的自然通风,排出室内污染物的速率很快,通风效率很高,能够明显改善室内空气品质。机械通风数值模拟结果表明,换气次数、排风速度以及进风口位置都会影响室内污染物的浓度分布。换气次数增大时,排出室内污染物的能力增强;相同的排风量下,增大排风速度,通风效率改变不大;排风口位置不变,进风口位置下移时,通风效率增大。研究结果表明,自然通风时,室内的污染物浓度在空间高度上的变化较小,分布比较均匀;机械通风时,室内污染物浓度在空间高度上呈现下高上低的浓度分层分布。更多还原

【Abstract】 With the development of social economy, more and more buildings are massively decorated, plus the need of energy conservation, the room airtight is strengthened, which cause massive low density volatile organic compounds exist in the room, they will be harm to the human body. Studying on the interior contaminant distribution characteristic and appraising discharging pollutant ability of different ventilation pattern are one of important job on building environment studies, which is very important to perfect valuation system of indoor air quality, to design building ventilation system, and consider interior air quality in engineering design.Indoor air quality、ventilation efficiency and ventilation pattern was introduced in this paper. Summed up the present situation and existed problems of indoor air quality and CFD research, combined numerical simulation and experiment method, made use of computational fluid dynamics software PHOENICS, by means of many times simulation, selected the mathematic model describing the pollutant distribution and set pollution source reasonably. Tested the formaldehyde concentration of air-conditioning room, verified the correctness of simulation procedure. Aimed at energy conservation demonstrated building, discussed the effect of natural ventilation and mechanical ventilation on indoor pollutant distribution, discussed the effect of inlet position and inlet area of natural ventilation on indoor pollutant distribution, and discussed the effect of air exchange rate and velocity of mechanical ventilation on indoor pollutant distribution.The experiment results show that, the natural ventilation of demonstrated building could discharge indoor pollutant effetely; the tested results of natural ventilation show that, the HCHO and TVOC concentration of decorated building can satisfy the indoor air quality standard after one year; the tested results of mechanical ventilation show that, the effect of ventilation quantity on indoor pollutant distribution is not obvious, the velocity of discharging indoor pollutant with the maximum is lower than natural ventilation.The numerical simulation results of natural ventilation show that, inlet position、inlet area and inlet temperature can influence the indoor pollutant distribution, when half area of east and west window open, indoor pollutant can be discharged effetely; Enlarge area of inlet, the ability of discharging indoor pollutant is strengthened; in autumn, natural ventilation under wind and hot pressure can discharge indoor pollutant quickly, the ventilation efficiency is very high, natural ventilation can improve indoor air quality obviously. The pollutant distribution under natural ventilation is homogeneous on height direction.The numerical simulation results of mechanical ventilation show that, the air exchange rate, exhaust velocity and inlet position can influence indoor pollutant distribution. When air exchange rate increase, the ability of discharging indoor pollutant is strengthened; when exhaust velocity increases, ventilation efficiency also increases; the outlet position keeps invariant, change the inlet position, the ventilation efficiency also increases. The pollutant concentration of mechanical ventilation is high at the bottom of room and low at the upper part of room.更多还原