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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
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9 @! R3 V! s0 ]: B- Q" tA water drop strikes the water-averse wing of a Morpho 3 w9 N b$ q1 `0 s2 e5 z
butterfly. There are many uses for surfaces that can stay dry, self-clean or 8 w" f7 l8 J$ m7 d
resist icing. Liquid drops hitting such surfaces tend to spread out and then
$ e- c3 D: K1 k* n, ]retract before finally bouncing. Many applications benefit from minimizing the
& h6 ~1 s0 {1 E7 @+ x* S% wcontact time between drop and surface, which is generally assumed to occur if 2 |6 V) z$ \* D9 C5 n( A
the impacting drop deforms symmetrically. Kripa K. Varanasi and colleagues now - k- x! Y, h8 i/ q. S \ D, t+ P
show that drops bounce off faster from a superhydrophobic surface with a
u0 f, n) ]( r E* F/ i ~morphology that redistributes the liquid mass so that it no longer spreads and
9 q7 F3 L6 R8 `) O' {- Mretracts symmetrically. Theory and experiments confirm that this strategy : _ y9 r) o( @( o/ I. C- Y0 e
shortens the contact time between a bouncing drop and a surface beyond what was
5 |2 i4 a0 \( |' h# Uthought possible. Photo: A. T. Paxson, K. Hounsell, J. W. Bales, J. C. Bird * U% ?4 y( W! y, L5 g3 i
& K. Varanasi.& ]) A8 ]: i8 v4 u9 d9 j5 e* E) L' }6 [- n
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发表于 2013-11-22 18:25
发表于 2013-11-23 19:31
