固い超水性表面で自発的なドロップレットトランポリン

Thomas M Schutzius¹, Stefan Jung¹, Tanmoy Maitra¹

¹Laboratory of Thermodynamics in Emerging Technologies, Department of Mechanical and Process Engineering, ETH Zurich, 8092 Zurich, Switzerland.

Nature

|November 6, 2015

まとめ

低圧の超水表面は水滴を浮遊させ,反発させ,自己浄化と防氷を可能にします. この現象は,急速な蒸発によって引き起こされ,効率的なドロップレットの除去のために表面粘着を克服します.

科学分野:

表面科学
流体力学
熱力学について

背景:

凝縮物質の自発的除去は,自己浄化,防氷,凝縮制御技術にとって不可欠です.
自発的なドロップレット除去のメカニズムを理解することは不完全であり,合理的な表面設計を妨げています.

研究の目的:

低圧環境における超水表面での水滴の自己除去メカニズムを調査する.
蒸発,表面の質感,そしてドロップレット表面の相互作用がドロップレット浮揚と反発における役割を明らかにする.

主な方法:

水滴の振る舞いの実験的観測超水質の表面.
浮揚,反転,蒸発率を含むドロップレットダイナミクスの分析.
低圧環境がドロップレットと表面の相互作用に及ぼす影響を調査する.

主要な成果:

低圧で超水表面の水滴は,自発的に浮上し,トランポリンのように跳ね上がります.
ドロップレット-表面衝突は,急速な蒸発によって生成される蒸気過圧のために,統一よりも大きい還元係数を示します.
蒸発による冷却は,超冷却ドロップルの凍結を引き起こし,浮揚を促進し,自発的な氷の除去を可能にします.

結論:

表面の質感は液体と凍結水滴の保持を防ぐドロップレット表面の相互作用を誘導することができます.
蒸発と制限された蒸気流によって引き起こされる観測された現象は,自己浄化と防氷表面のための新しいメカニズムを提供します.
現在低圧環境に限定されていますがこの研究は設計された表面上の滴の振る舞いを制御する洞察を提供します

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