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- 积分
- 17983
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- 17983
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- 26159
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2013年11月21日 Nature! K) e) v3 _9 x# {
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A water drop strikes the water-averse wing of a Morpho
, Z3 F, C/ |6 R6 `0 _8 ]2 Cbutterfly. There are many uses for surfaces that can stay dry, self-clean or 8 h6 G1 F: d2 t- I& ~
resist icing. Liquid drops hitting such surfaces tend to spread out and then
$ Q3 }( t5 e5 Eretract before finally bouncing. Many applications benefit from minimizing the
5 ~% }3 U3 c& s3 P) Scontact time between drop and surface, which is generally assumed to occur if ' p" p* M, n9 `3 J- o
the impacting drop deforms symmetrically. Kripa K. Varanasi and colleagues now , p1 X3 v3 G) Z; Q2 T
show that drops bounce off faster from a superhydrophobic surface with a
" J; t7 y( A# h" U5 b" S3 ^morphology that redistributes the liquid mass so that it no longer spreads and & |# w( V p9 ^' V1 U! ~8 e" \, q" a
retracts symmetrically. Theory and experiments confirm that this strategy
$ {1 m, l7 b& d. x1 Cshortens the contact time between a bouncing drop and a surface beyond what was
+ R8 v. n; J, a/ J1 ]/ ?4 E q6 F5 X$ ythought possible. Photo: A. T. Paxson, K. Hounsell, J. W. Bales, J. C. Bird
4 g5 L8 u$ }4 o% y1 f& K. Varanasi.
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发表于 2013-11-22 18:25
发表于 2013-11-23 19:31
