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羽ばたき足のデルタ翼機能は,鳥の泳ぎの推進のために水力動力学的持ち上げを与えます
L Christoffer Johansson1, R Ake Norberg
1Department of Organismic and Evolutionary Biology, Harvard University, 26 Oxford Street, Cambridge, Massachusetts 02138, USA.
Nature
|July 4, 2003
まとめ
泳ぐ鳥は2段階の足の推進戦略を使用しています. 当初,ドラッグは動きに力を与え,ストロークの後に継続的な推力生成のためにリフトに移行します.
科学分野:
- バイオメカニクス バイオメカニクス
- 水力ダイナミクスとは
- 動物の移動 動物の移動
背景:
- 泳ぐ鳥は,羽ばたきのある足を使って動いている.
- 足の動きは,パワーストロークの間,曲線状の軌道をたどります.
- 足の向きは,ストロークを通して変化し,水力力学的な力に影響します.
研究 の 目的:
- 鳥の足で運動する泳ぎの水力力学的メカニズムを調査する.
- ドラッグベースの推進とリフトベースの推進の間の移行を明らかにする.
- 足の形状が継続的な推力生成にどのように寄与するかを理解する.
主な方法:
- パワーストロックの時の足の軌道の分析.
- ハイドロダイナミック・フォース・アナリストは,ドラッグとリフトのコンポーネントを区別する.
- 渦の動力学を研究し,付着した渦と脱落した渦を観察する.
主要な成果:
- 推進力は最初,パワーストロックの初期にドラッグ・ドミナントである.
- リフトベースの推進への移行は,ストロークの後に起こります.
- 渦は,シェードと先端のタイプに固定され,リフト生成を容易にします.
結論:
- 網状の足は,二重モードメカニズムを通じて推進力を発生します.
- 網状足のデルタ形は,ドラッグとリフトフェーズによる継続的な推力を可能にします.
- この研究は,鳥の泳ぎにおける水力学と運動学の複雑な相互作用を明らかにしています.
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