流体粒子の加速は,完全に発達した渦巻力において起こります
A La Porta1, G A Voth, A M Crawford
1Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853-2501, USA.
Nature
|March 10, 2001
まとめ
研究者は,流動的な水流で流体粒子の加速を測定し,高レイノルズ数でのコルモゴロフスケーリングを確認しました. 粒子加速は極めて断続的で,極端な値に達することが判明した.
科学分野:
- 流体力学 流体力学
- トルブルンスの研究
- 統計物理学 統計物理学とは
背景:
- 乱流中の粒子の動きは,輸送と混合に不可欠です.
- 流体粒子の加速を理解することは,コルモゴロフの1941年のスケーリングのような乱流理論を検証する鍵です.
- 以前の研究では,粒子の加速を正確に測定する課題に直面していました.
研究 の 目的:
- 流体粒子の加速を乱流で実験的に調査する.
- コルモゴロフの理論に基づくハイゼンベルク-ヤグロム予測を検証するために.
- 粒子加速の断続性とスケーリングを定量化するために.
主な方法:
- 粒子を追跡するために,高エネルギー物理学から適応された検出器を使用しました.
- 実験室で実験を行いました.
- レイノルズ数は6万3000に達した.
主要な成果:
- 高レイノルズ数での加速変数のコルモゴロフスケーリングの観測,実験誤差の範囲内.
- 粒子加速が非常に断続的であることが判明し,ピークは重力の1500倍にまで達します.
- 加速データは,すべてのテストされたレイノルズ数における大規模な流れのアニソトロピーを反映していることに注意してください.
結論:
- 実験結果は,流体粒子の加速度に関するコルモゴロフのスケーリング理論を支える.
- 加速の極端な断続性は,乱流の重要な特徴を強調しています.
- 大規模な流れのアニゾトロピーは,研究されたすべてのスケールでの粒子加速に影響します.
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