横向きに移動する波で壁の乱れを抑制する
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Division of Applied Mathematics, Brown University, Providence, RI 02912, USA.
Science (New York, N.Y.)
|May 20, 2000
まとめ
壁に囲まれた流れにおける乱流の発生は,横横に移動する波によって抑制され,壁の近くの線引きをなくし,切断ストレスを軽減します. この効率的な方法は,塩水のアプリケーションにおける刺激のために電磁性タイルを使用しています.
科学分野:
- 流体力学 流体力学
- トルビュランスの制御
- 応用電磁学について
背景:
- 壁の中の乱流は,大きな抵抗とエネルギー損失を生成します.
- 壁付近の渦巻を制御することは,さまざまなエンジニアリングアプリケーションの効率を改善するために不可欠です.
- 既存の渦巻制御方法には,効率や有効性の限界があることが多い.
研究 の 目的:
- 横横に移動する波を用いて,乱流生成の抑制を調査する.
- この波が壁付近の線条や切断ストレスに与える影響を分析する.
- 移動波を誘導するための実用的で効率的な方法を示す.
主な方法:
- 直接数値シミュレーション (DNS) を用いて,壁に囲まれた渦巻流をモデル化しました.
- フロービジュアライゼーションは,壁の近くにある構造物の振る舞いを観察するために使用されました.
- 粘性亜層に閉じ込められたスパンウェイズ力が理論的かつ実験的に適用されました.
- 電気磁気タイルが利用され,海水中の移動波の刺激を効率的に発生させました.
主要な成果:
- 直接的な数値シミュレーションにより,横向きに移動する波が乱流の発生を抑制することを確認しました.
- フロービジュアライゼーションでは,壁付近の線条の除去が示され,これは他の方法と比較してユニークな結果でした.
- 壁切断のストレスを大幅に削減することが達成されました.
- 移動する波は,高効率の電磁タイルによって生成されたスパンウェイズ力によって効果的に誘発されました.
結論:
- 横横に移動する波は,乱流抑制の新しく効果的な方法を提供します.
- 壁付近の線条の除去は,大幅な抵抗の減少につながります.
- 電磁タイル配列は,この制御戦略を,塩水の流れのような現実のアプリケーションで実装するための効率的かつ実用的手段を提供します.
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