| Project/Area Number |
09650625
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Building structures/materials
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| Research Institution | KYOTO UNIVERSITY |
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Principal Investigator |
KATSURA Junji Kyoto University, D.P.R.I., Professor, 防災研究所, 教授 (20034340)
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| Co-Investigator(Kenkyū-buntansha) |
HAYASHI Taiichi Kyoto University, D.P.R.I., Assistant professor, 防災研究所, 助教授 (10111981)
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| Project Period (FY) |
1997 – 1998
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| Project Status |
Completed (Fiscal Year 1998)
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| Budget Amount *help |
¥1,900,000 (Direct Cost: ¥1,900,000)
Fiscal Year 1998: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1997: ¥1,200,000 (Direct Cost: ¥1,200,000)
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| Keywords | atmospheric pressure / planetary boundary layer / natural wind / atmospheric turbulence / quasi-steady / wind pressure measurement / 気圧変動 / 気圧計測 / 乱流スケール / 流形形成長さ |
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| Research Abstract |
A hollow globe with small protuberances and holes on the surface acts as a dynamic pressure sensor by measuring the wind force and does as a reference pressure sensor by modifing the intenal pressure. On the surface of globe there are 361 holes at the center of each protuberance which is evenly arranged in accordance with the geometric position of the 122 vertexes (including one for conducting tube) and the 240 triangle gravity centers of the inscribed 240 polyhedron.
The internal pressure of the hollow globe evenly perforated was successfully divided into the approaching wind effect and the reference atmospheric pressure, utilizing the omnidirectionality for the internal pressure and the drag force against wind direction change. The 300 times scale ratio of the globe size to the length scale of turbulence kept a quasi-steady state, and so a uniform stream in a wind tunnel was available to measuring the pressure and drag coefficients. Although the apparatus had a small defect for the measurement of the drag force, it worked well under the limited conditions of the horizontal dynamic pressure and a long duration of time. It was found that the reference pressure fluctuation during several minutes was often stronger in the test field than that of the wind pressure.
The result of the research is presented at the 10 th International Conference on Wind Engineering held in Copenhagen with the title "On a reference pressure detecter and an example of field data in a natural wind".
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