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- 积分
- 17983
- 威望
- 17983
- 包包
- 26159
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2013年11月21日 Nature
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1 F9 L/ K0 z$ u9 j: VA water drop strikes the water-averse wing of a Morpho
4 `; f4 |. R; X. f' jbutterfly. There are many uses for surfaces that can stay dry, self-clean or 5 w! e9 ]$ V' q6 ~* U" ]
resist icing. Liquid drops hitting such surfaces tend to spread out and then & @/ d- M8 }/ w& e
retract before finally bouncing. Many applications benefit from minimizing the
+ b/ A6 _. q5 Q* Hcontact time between drop and surface, which is generally assumed to occur if ; G( J3 q5 i _+ F- `
the impacting drop deforms symmetrically. Kripa K. Varanasi and colleagues now - r' h' z% X. q# H$ c1 j: X
show that drops bounce off faster from a superhydrophobic surface with a
; Q3 N d, _* v- ^9 m# h/ ?morphology that redistributes the liquid mass so that it no longer spreads and % @$ Q4 h: f1 J* w2 g7 K
retracts symmetrically. Theory and experiments confirm that this strategy 6 m1 e+ a- P4 i: o7 V0 B
shortens the contact time between a bouncing drop and a surface beyond what was + I0 `4 ~: U2 t8 V! R
thought possible. Photo: A. T. Paxson, K. Hounsell, J. W. Bales, J. C. Bird
J6 ]+ n7 D+ ~. s: {& K. Varanasi.8 {) h: |/ L3 Z) A. q
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# d! l" @$ E* v) }/ {; ^1 a2 N% V) F, G* ]# u6 U. d
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发表于 2013-11-22 18:25
发表于 2013-11-23 19:31
