The Impact of Flow Field and Diffusion by Roughness of Surface
碩士 === 淡江大學 === 水資源及環境工程所 === 82 === The diffusion of air pollutants over complex terrain is affected by the complicated wind field generated by topography. Because it is very difficult to predict the wind field by simple mathematical model in complex ter...
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1994
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ndltd-TW-082TKU000870082016-02-08T04:06:31Z http://ndltd.ncl.edu.tw/handle/23732746015231350875 The Impact of Flow Field and Diffusion by Roughness of Surface 模型表面粗糙度對附近流場與擴散的影響 S. T. Guo 郭世聰 碩士 淡江大學 水資源及環境工程所 82 The diffusion of air pollutants over complex terrain is affected by the complicated wind field generated by topography. Because it is very difficult to predict the wind field by simple mathematical model in complex terrain, wind tunnel experiments are widely used for this task in the past. The method used for constructing the physical models will affect the results wind tunnel experiments. In this study, the transport and diffusion of a pollutants near a three dimensional Gaussian hill is investigated. Three different methods were used to construct the models. The first models are "stepped" models constructed by Styrofoam with different thickness. The third model is also constructed by Styrofoam but its surface was smoothed by fill in. The flow field is measured by X-type hot film anemometers. The diffusion experiments have been simulated by SF6 which is measured by a ECD GC. From the results of experiments we found the wind field and concentration near ground surface were strongly affected by the surface roughness of the models, especially in the lee side of the hill. H. C. Chiang 江旭程 1994 學位論文 ; thesis 63 zh-TW |
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碩士 === 淡江大學 === 水資源及環境工程所 === 82 === The diffusion of air pollutants over complex terrain is
affected by the complicated wind field generated by topography.
Because it is very difficult to predict the wind field by
simple mathematical model in complex terrain, wind tunnel
experiments are widely used for this task in the past. The
method used for constructing the physical models will affect
the results wind tunnel experiments. In this study, the
transport and diffusion of a pollutants near a three
dimensional Gaussian hill is investigated. Three different
methods were used to construct the models. The first models are
"stepped" models constructed by Styrofoam with different
thickness. The third model is also constructed by Styrofoam but
its surface was smoothed by fill in. The flow field is measured
by X-type hot film anemometers. The diffusion experiments have
been simulated by SF6 which is measured by a ECD GC. From the
results of experiments we found the wind field and
concentration near ground surface were strongly affected by the
surface roughness of the models, especially in the lee side of
the hill.
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author2 |
H. C. Chiang |
author_facet |
H. C. Chiang S. T. Guo 郭世聰 |
author |
S. T. Guo 郭世聰 |
spellingShingle |
S. T. Guo 郭世聰 The Impact of Flow Field and Diffusion by Roughness of Surface |
author_sort |
S. T. Guo |
title |
The Impact of Flow Field and Diffusion by Roughness of Surface |
title_short |
The Impact of Flow Field and Diffusion by Roughness of Surface |
title_full |
The Impact of Flow Field and Diffusion by Roughness of Surface |
title_fullStr |
The Impact of Flow Field and Diffusion by Roughness of Surface |
title_full_unstemmed |
The Impact of Flow Field and Diffusion by Roughness of Surface |
title_sort |
impact of flow field and diffusion by roughness of surface |
publishDate |
1994 |
url |
http://ndltd.ncl.edu.tw/handle/23732746015231350875 |
work_keys_str_mv |
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