A prediction model for wind speed ratios at pedestrian level with simplified urban canopies

Naoki Ikegaya, Y. Ikeda, Aya Hagishima, A. A. Razak, Jun Tanimoto

研究成果: ジャーナルへの寄稿記事

9 引用 (Scopus)

抄録

The purpose of this study is to review and improve prediction models for wind speed ratios at pedestrian level with simplified urban canopies. We adopted an extensive database of velocity fields under various conditions for arrays consisting of cubes, slender or flattened rectangles, and rectangles with varying roughness heights. Conclusions are summarized as follows: first, a new geometric parameter is introduced as a function of the plan area index and the aspect ratio so as to express the increase in virtual density that causes wind speed reduction. Second, the estimated wind speed ratios in the range 0.05 < z/h < 0.3, where h is the building height, are consistent with those derived from the database to within an error of ±25%. Lastly, the effects of the spatial distribution of the flow were investigated by classifying the regions near building models into areas in front of, to the side of, or behind the building. The correlation coefficients between the wind speeds averaged over the entire region, and the front or side region values are larger than 0.8. In contrast, in areas where the influence of roughness elements is significant, such as behind a building, the wind speeds are weakly correlated.

元の言語英語
ページ(範囲)655-665
ページ数11
ジャーナルTheoretical and Applied Climatology
127
発行部数3-4
DOI
出版物ステータス出版済み - 2 1 2017

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pedestrian
wind velocity
canopy
prediction
roughness
spatial distribution

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

これを引用

A prediction model for wind speed ratios at pedestrian level with simplified urban canopies. / Ikegaya, Naoki; Ikeda, Y.; Hagishima, Aya; Razak, A. A.; Tanimoto, Jun.

:: Theoretical and Applied Climatology, 巻 127, 番号 3-4, 01.02.2017, p. 655-665.

研究成果: ジャーナルへの寄稿記事

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