垂直表面の昼間放射性冷却
Fei Xie1,2, Weiliang Jin3,4, J Ryan Nolen5
1GPL Photonics Laboratory, Key Laboratory of Luminescence Science and Technology, Chinese Academy of Sciences & State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun, 130033, China.
Science (New York, N.Y.)
|November 14, 2024
まとめ
垂直の表面でも動作します 垂直の表面でも動作します この新しい放射冷却法では 直接的な太陽光下でも 室内の温度を保ち 建物や車両の用途を拡大します
科学分野:
- 材料科学
- 熱力学について
- 光学について
背景:
- 日中の環境下での放射性冷却は,空間に熱放射線を放つことで,周囲の温度を下げます.
- 現在の方法は天井面に限られており,建物や車両などの垂直構造の応用が制限されています.
研究 の 目的:
- 直射太陽光下にある垂直表面の昼間放射性冷却を実証する.
- 空に面していない表面での実用的なアプリケーションに適した新しい熱エミーターを開発する.
主な方法:
- 階層的に設計された,角度非対称な,スペクトル的に選択的な熱放出器の製造.
- 太陽光のピーク条件 (約920W/m2) でエミッターの性能をテストする.
- シリカポリマーハイブリッドの放射冷却器と商用ホワイトペイントとの比較分析
主要な成果:
- 開発されたエミターは,ピークの太陽光の下の垂直表面でサブ環境温度を達成しました.
- エミーターは周囲の温度より約2.5°C低い温度に達した.
- これは,ハイブリッドクーラーとホワイトペイントと比較して,それぞれ4.3°Cと8.9°Cの温度低下を示し,既存の技術に比べ,著しい改善を示しています.
結論:
- 垂直面での日中の放射性冷却の実現可能性を示した.
- この新しいエミーターの設計は,以前の空面のみのアプローチの限界を克服しています.
- 都市環境や様々な構造物での受動的な冷却の広範な適用を可能にします.
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