パイプの流れにおける乱流の発生
Kerstin Avila1, David Moxey, Alberto de Lozar
1Max Planck Institute for Dynamics and Self-Organization, Göttingen, Germany. kavila@ds.mpg.de
Science (New York, N.Y.)
|July 9, 2011
まとめ
パイプの流れにおける一時的な乱流は,臨界のレイノルズ数で持続する. 時間の複雑さではなく,混沌とした領域の空間的広がりが,この流体乱流を駆動しています.
科学分野:
- 流体力学 流体力学
- 渦巻力理論とは,渦巻力理論である.
背景:
- シーアフローは,速度が増加するにつれて,ラミナーから渦巻運動に移行する.
- 渦巻の発生は,輸送効率と混合を大幅に変化させます.
- パイプの流れにおける持続的な乱流に対するクリティカルなレイノルズ数は,未だに難解である.
研究 の 目的:
- パイプの流れにおける乱流の維持に責任を負うプロセスを特定し,特徴づけること.
- 臨時的な乱れが持続する臨界点を決定する.
- 乱流の発生のメカニズムを,古典的なランドー・ルエル・タケンズ理論と対比する.
主な方法:
- 広範な実験調査.
- 総合的なコンピュータシミュレーション.
主要な成果:
- 低レイノルズ数での一時的な乱れは,パイプの明確な臨界点で持続します.
- この研究では,乱流を維持する主要なプロセスを特定し,特徴づけました.
- 時間の複雑性の増加ではなく,混沌とした領域の空間的増殖が決定的な要因として特定されました.
結論:
- パイプ内の流体の乱流は,混沌とした領域の空間的な広がりによって維持されます.
- この発見は,時的複雑性から生じる乱流の古典的な見解に異議を唱える.
- この研究は,流体乱流の根本的な性質に関する新しい視点を提供しています.
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