センチメートルのスケールで不均質な雲の混合のホログラム測定
Matthew J Beals1, Jacob P Fugal2, Raymond A Shaw3
1Atmospheric Sciences Program, Michigan Technological University, Houghton, MI 49931, USA.
まとめ
雲の混じり合いは 雲と澄んだ空間の 鋭い移行を引き起こします 空中ホログラム画像は ドロップレットの大きさの分布が局所的に変動していますが,平均直径は一貫しています.
科学分野:
- 大気科学
- 雲の物理
- トルブランス
背景:
- 雲の光学特性と降水量は,乱れ混合に依存しています.
- 混合は均等な蒸発や選択的なドロップレットの消失につながります.
研究 の 目的:
- 雲の空間構造と小さな乱流のスケールでの滴の大きさの分布を視覚化します.
- 雲の反応を観察し,きれいな空気と混合する.
主な方法:
- 空中ホログラム画像が使われた
- 分析は消散性スケール (<1センチメートル) に焦点を当てた.
主要な成果:
- 渦巻雲は不均一で 雲と空気の交差が鋭い.
- 局所滴数密度は大きく変動する.
- 平均滴径は変動にもかかわらずほぼ一定である.
結論:
- 雲のない空気のインターフェースは,非常に小さなスケールで持続します.
- ドロップレット蒸発のダイナミクスは複雑でスケールに依存しています.
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