The Study on Generation Method of Environmental Negative Air Ions
Date Issued
2005
Date
2005
Author(s)
Weng, Chiao-Ling
DOI
zh-TW
Abstract
According to many research reports, the air ions in the atmosphere would affect the health of the human body. The concentration of air ions can reflect the degree of the air pollution directly in the present environment. The relative literatures indicate that the negative air ions (NAIs) have the positive effect on the human health. The in-situ monitor of air ion concentrations in the urban area is performed in this study. The concentrations of the positive and negative air ions in the fountain area are analyzed to obtain the relative information. On the other hand, the NAIs are generated from the mechanism of the breakup of water droplets by the lab atomizer in this study. The relationship between the concentration of NAIs and the operating condition is investigated.
There are four monitoring sites for the measurement of background air ions in the fountain-containing area, including the first floor of Taipei County Government building, the open space of Yungho Jen-AI park, the back door of Taipei Metro Mall, and the cross section of Song-Shou and Keelung Roads. The average concentration of NAIs in these background sites is between 641 and 1131 ions/cm3. The concentration of the positive air ions (PAIs) is greater than that of NAIs with the concentration ratio of PAIs/NAIs of 1.1 in the traffic region due to the heavy vehicle transportation and human activities. However, the concentration of NAIs is higher than that of PAIs in the open space of Yungho Jen-AI park due to less air pollution sources. The concentration of NAIs is about 3.7 times that of PAIs with the concentration ratio of PAIs/NAIs of 0.27. The four sampling points of the fountain scenes includes the indoor waterfall in the building of Taipei County Government, the outdoor waterfall in Yungho Jen-AI park, the fountain in front of Taipei Metro Mall, and the fountain near the cross section of Xinyi and Keelung Roads. The average concentration of NAIs around the fountain scenes is between 38,320 ~ 263,863 ions/cm3. Among all, the concentration of NAIs near the fountain in front of Taipei Metro Mall is highest.
The atomization system is employed to simulate the generation of NAIs by the breakup of water droplets in the laboratory. There are two atomized water sources and three different pressures. The results show that the concentration of NAIs is higher when the water source is clearer. The NAIs generated from the atomization of pure water is about 3.4 ~ 16.4 times that of tap water. The concentration of NAIs increases with the pressure of atomization. For example, the concentration of NAIs generated at the atomization pressure of 30 PSI is higher as 3.6 to 8.7 times that of 20 PSI.
Subjects
空氣負離子
噴水造景
水滴破碎
霧化
Negative air ions
fountain scene
water droplet breakup
atomization
Type
thesis
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