スパンウェイズフローと,先端の渦が昆虫の翼に固定される
1Department of Integrative Biology, University of California, Berkeley 94720, USA.
Nature
|August 17, 2001
まとめ
昆虫の翼は,飛行性能に不可欠な先端渦を保持しています. この研究は,デルタ翼航空機の類似性を否定し,スパンウェイズフローではなく,尖端渦がこれらの重要な空気力学的構造を安定させることを明らかにします.
科学分野:
- 流体力学 流体力学
- エアロダイナミクス エアロダイナミクス
- バイオインスピレーションによるエンジニアリング
背景:
- 最先端の渦は,昆虫の飛行効率の鍵である.
- 2Dのフローにおける渦の分離は,3Dのフラッパーウィングにおける固定メカニズムを必要とします.
- 現在の理論では,デルタ翼の航空機と同様に,スパンバイズフローがこれらの渦を安定させることを提案しています.
研究 の 目的:
- 飛ぶ昆虫の翼に先端渦が付着するメカニズムを調査する.
- スパンウィズフローが最先端の渦を安定させるという仮説を検証するために.
- 昆虫の飛行における渦の安定性の代替メカニズムを探求する.
主な方法:
- 流れ構造をマッピングするために,動的にスケールされたモデル昆虫を使用しました.
- モデルによって生成された同時に測定された空気力学力.
- フェンスやエッジバッフルを使用して,スパンウェイズフローを体系的に変更しました.
主要な成果:
- 昆虫の翼を叩くことは,関連するレイノルズ数でデルタ翼の航空機に匹敵する渦巻き渦巻きを生成しません.
- スパンウェイズフローの制限は,先端渦の分離を誘導しませんでした.
- 実験データは,尖端渦を含む別の仮説を裏付けている.
結論:
- 昆虫の翼の先端渦を安定させるメカニズムは,デルタ翼の航空機のメカニズムとは異なる.
- スパンウェイズフローは,昆虫の飛行における渦の解離を防ぐ主な要因ではありません.
- 尖端渦によって誘発される下向きの流れは,先端渦の成長を制限し,結合を維持するように見える.
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