| Item type |
テクニカルレポート / Technical Report(1) |
| 公開日 |
2015-03-26 |
| タイトル |
|
|
タイトル |
自動追尾型風向風速測定器 |
| 言語 |
|
|
言語 |
jpn |
| 資源タイプ |
|
|
資源タイプ識別子 |
http://purl.org/coar/resource_type/c_18gh |
|
資源タイプ |
technical report |
| その他のタイトル（英） |
|
|
その他のタイトル |
Automatic-Tracking-Type Flow Direction and Velocity Meter |
| 著者 |
川端, 長勝
中谷, 輝臣
KAWAHATA, Nagakatsu
NAKAYA, Teruomi
|
| 著者所属 |
|
|
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航空宇宙技術研究所新型航空機部 |
| 著者所属 |
|
|
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航空宇宙技術研究所空気力学第二部 |
| 出版者 |
|
|
出版者 |
航空宇宙技術研究所 |
| 出版者（英） |
|
|
出版者 |
National Aerospace Laboratory(NAL) |
| 書誌情報 |
航空宇宙技術研究所資料
en : Technical Memorandum of National Aerospace Laboratory
巻 172,
p. 12,
発行日 1970-03
|
| 抄録（英） |
|
|
内容記述タイプ |
Other |
|
内容記述 |
An automatic flow meter which can be used for the measurement of the velocity and the direction of wind flow in a localized flow field has been developed. Its main part consists of a pitot head, pressure transducers, and servo mechanisms which enable the pitot head to rotate and follow the flow direction. The pitot head is composed of five small tubes, one at the center and four on the periphery, having a cross-like shape in the frontal view. These tubes are soldered together and enclosed within an outer shell tube, the space between them being filled up. The four periphery tubes are cut off at 60 degrees apex angle so that the tip of the pitot head is something like a truncated pyramid with pressure tappings on the four side faces and on the apex. The pitot head is mounted on a circular-arc guide rail and can be rotated by a servo motor around its pitch axis, and the guide rail and the pitot head can also be rotated as a whole around their yaw axis. Both of these axes are aligned to pass through the tip of the central tube, so that the pitot tip keeps its position during the rotation. The pressure difference taken from each pair of pressure tappings situated on opposite side of the central tube gives the signal of the direction of the flow (pitch and yaw, respectively), The principle for determining the flow speed by this device is that the pressure difference between the central hole and any one of the others is proportional to the dynamic pressure of the flow, and that its proportional constant is unique for the truncated pyramid type head when it is aligned with the flow direction. The instrument was tested in a wind tunnel over a wide range of flow speeds and was found to be efficient. The accuracy in the directional finding of this instrument is better than 0. 5 degrees at a flow velocity higher than 8 m/sec. The error of the measurement of the flow velocity is about +1. 5 m/sec and it is clearly caused by noise in the electric circuit. Because of its smallness and the simplicity of its mechanism, the instrument is expected to be widely applied in the field of flow measurements. A measured flow field behind a wing immersed in the propeller slipstream is presented as an example of the application of this instrument. The frequency response characteristics measured in a fluctuating flow are also shown. |
| ISSN |
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収録物識別子タイプ |
ISSN |
|
収録物識別子 |
0452-2982 |
| 書誌レコードID |
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|
収録物識別子タイプ |
NCID |
|
収録物識別子 |
AN00314334 |
| 資料番号 |
|
|
内容記述タイプ |
Other |
|
内容記述 |
資料番号: NALTM0172000 |
| レポート番号 |
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|
内容記述タイプ |
Other |
|
内容記述 |
レポート番号: NAL TM-172 |
naltm00172.pdf (1.2 MB)
