空間的に断続的な流れにおける乱流の排除
Björn Hof1, Alberto de Lozar, Marc Avila
1Max Planck Institute for Dynamics and Self-Organisation, Bunsenstrasse 10, 37073 Göttingen, Germany. bhof@gwdg.de
Science (New York, N.Y.)
|March 20, 2010
まとめ
研究者らは,スイアから渦巻きにエネルギーを供給することによって,パイプの流れの乱流を増幅するメカニズムを発見しました. 速度プロファイルの屈折点をターゲットにした単純な制御は,乱流を崩壊させ,フローをリラミナライズすることができます.
科学分野:
- 流体力学 流体力学
- トルブルンスの研究
- 非線形ダイナミクス 非線形ダイナミクス
背景:
- パイプや運河で流体輸送は,自然と産業において至るところに存在する.
- ラミナーフローは,摩擦による損失が低いため,エネルギー効率が高くなります.
- ほとんどの実用的な流れは乱流であり,中程度の速度であっても,干渉に対する感受性のために乱流である.
研究 の 目的:
- 乱流における渦の運動と空間的分布を調査する.
- 平均切断から渦巻渦巻へのエネルギー移転メカニズムを明らかにするために.
- 乱流の軽減のための制御戦略を特定する.
主な方法:
- 渦のダイナミクスと空間分布の分析.
- エネルギー増幅メカニズムを特定する.
- 速度プロファイルの転向点をターゲットとする制御メカニズムの実装.
主要な成果:
- 増幅メカニズムが発見され,エネルギーが平均シアから乱暴な渦に転送される.
- 単純な制御戦略は,このエネルギー転送を効果的に妨害します.
- コントロールを起動すると,即座に渦巻が崩壊し,フローがリラミナライズされます.
結論:
- 乱流のパイプとチャネルの流れは,特定のメカニズムをターゲットにすることで制御できます.
- 速度プロファイルに標的を絞った介入によって再ラミナライゼーションは達成可能である.
- この研究は,流体流動効率の制御に関する洞察を提供します.
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