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- 积分
- 17983
- 威望
- 17983
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- 26159
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2013年11月21日 Nature' s! k7 d) {2 F3 a6 w5 H
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A water drop strikes the water-averse wing of a Morpho
' q& B( o1 J# f2 f; [+ kbutterfly. There are many uses for surfaces that can stay dry, self-clean or
* I" ]1 }! a, _6 Bresist icing. Liquid drops hitting such surfaces tend to spread out and then
: u3 b) F! e. Zretract before finally bouncing. Many applications benefit from minimizing the
2 A) g. R& S' I( ?% H- j/ q# _9 Zcontact time between drop and surface, which is generally assumed to occur if % K0 i! K4 R/ \3 m0 A
the impacting drop deforms symmetrically. Kripa K. Varanasi and colleagues now : M9 P5 F" J2 p# m6 K
show that drops bounce off faster from a superhydrophobic surface with a
) ?$ O5 h! a; y) {morphology that redistributes the liquid mass so that it no longer spreads and
, I6 O; ^# h; C, Q, z7 Rretracts symmetrically. Theory and experiments confirm that this strategy
, T1 {) c" N D- P% Mshortens the contact time between a bouncing drop and a surface beyond what was
# J% H0 f8 P _6 g& t& d1 h- }thought possible. Photo: A. T. Paxson, K. Hounsell, J. W. Bales, J. C. Bird
! u a1 _9 C: D* w$ S1 n( g& K. Varanasi.
: I1 x9 ^& _. s$ |( R7 j# [5 ^: Q I4 k, }9 v- O. a
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发表于 2013-11-22 18:25
发表于 2013-11-23 19:31
