室内空气流动速度对空气质量的影响(含任务书,开题报告,外文翻译,毕业论文12800字,答辩PPT)
摘 要
人们已经能越来越意识到室内空气质量对于健康重要性。甲醛是室内污染物的主要项目之一,为了保证人体健康,研究甲醛浓度随着时间的变化规律成了必要课题。本文研究了室内空气流动速度(内循环速度Vs)对于室内甲醛浓度随时间变化规律C=f(t)的影响。
利用小型环境测试舱动态平衡法,测定雪丰饰面板甲醛的即时散发率(采用酚试剂比色法测定室内空气中的甲醛即时浓度C,并换算成甲醛即时散发率R),绘制散发率—时间曲线,推导甲醛散发率—时间模型(R=f(t)),研究室内空气流动速度Vs对散发率模型的影响,完善室内污染物甲醛浓度预测模型(C=f(t))。
经实验得出:挥发系数较小的固态材料散发率通常呈指数衰减形式衰减,其模型: 或 ,其中R0为初始散发率(mg/m2/h),为衰减常数(m2/mg),t为时间(h)。在温度T、湿度RH、荷载率L、空气交换率N等实验条件不变的情况下,单独改变室内空气流动速度Vs (6m/h、10m/h、14m/h)。随着室内空气流动速度Vs上升,污染源的甲醛初始散发率R0增大,衰减系数k随之增大。且甲醛初始浓度C0 增大,甲醛浓度衰减速度加快。
关键词:室内空气质量;小型环境测试舱;甲醛;散发率—时间模型;空气流动速度
The influence of air flow speed on the indoor air quality
Abstract
With the improvement of living standards, people are aware of the importance of the indoor air quality for the health. Formaldehyde is an important item in the indoor pollutants, so the studying on the formaldehyde concentration varying over time is essential to ensure human health. This thesis focuses on the influence of air flow speed on the regular pattern of the formaldehyde concentration varying over time C=f(t).
The small environmental test chamber dynamic balance method is used to measure the formaldehyde emission rate of Xuefeng decorative plates with different air flow speeds. Formaldehyde immediate concentration is detected by phenol reagent spectrophotometry firstly, the immediate formaldehyde emission rate in the chamber calculated from the concentration secondly,the R-t curve is made and the formaldehyde emission rate VS time model is derived, then the air flow speed factor influence can be got. We can also derive formaldehyde concentration VS time model (C=f(t)) basing on the model of formaldehyde emission rate VS time.
The experimental results show: the emission rate of solid-state materials such as plates usually decrease over the time, and the emission rate attenuate model can be described as an exponential attenuate model, like or , where R0 is the initial dissemination the rate (mg/m2/h), k is the attenuation constant (m2/mg), and t is the time (h). When temperature T, humidity RH, load ratio L, air exchange ratio N are kept same, only the inner loop speed Vs (6m/h, 10m/h, 14m/h) is changed. With the inner flow speed Vs rising, the initial formaldehyde emission rate R0 would increase, and the attenuation coefficient k would increase; the initial formaldehyde concentration C0 would also increase and the decaying of the concentration would be faster.
Key words: indoor air quality, the small environmental test chamber, formaldehyde, emission rate model, air flow speed.
目 录
摘要 I
Abstract II
1 引言 1
2 实验方法 3
2.1 实验原理 3
2.2 实验原料和设备 4
2.3 实验条件 6
2.4 环境测试舱甲醛浓度(mg/m3)测定 7
2.5 材料中污染物散发率(mg/(m2h))的测定 8
3 结果与讨论 10
3.1 板材中甲醛散发率模型 10
3.1.1 散发率曲线测定 10
3.1.2 内循环空气流动速度对板材中甲醛散发率的影响 13
3.2 室内甲醛浓度预测模型 19
3.2.1 预测模型 19
3.2.2 预测模型的分析与求解 20
3.2.3 室内空气质量预测模型的验证 21
4 结论 22
参考文献 23
致谢 25
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