Difference between revisions of "Pearl drops"

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(Soft matter example)
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==Soft matter example==
 
==Soft matter example==
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For a flat uniform solid, the contact angle of a drop is given by Young's equation:
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                cosθ = (f<sub>sv</sub>-f<sub>sl</sub>)/f<sub>lv</sub>
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where f<sub>sv</sub>, f<sub>sl</sub>, f<sub>lv</sub> are surface tensions for solid/vapor, solid/liquid and liquid/vapor, respectively.
  
 
==Reference==
 
==Reference==

Revision as of 00:48, 9 March 2009

By Sung Hoon Kang


Title: Pearl drops

Reference: J. Bico, C. Marzolin and D. Quere, Europhys. Lett. 47, 220-226 (1999).

Soft matter keywords

hydrophobic, surface roughness, contact angle, Young's equation, surface tension, Wenzel's equation

Abstract from the original paper

If deposited on a hydrophobic rough substrate, a small drop of water can look like a pearl, with a contact angle close to 180. We examine the conditions for observing such a phenomenon and show practical achievements where the contact angle can be predicted and thus quantitatively tuned by the design of the surface microstructure.

Soft matter example

For a flat uniform solid, the contact angle of a drop is given by Young's equation:

               cosθ = (fsv-fsl)/flv

where fsv, fsl, flv are surface tensions for solid/vapor, solid/liquid and liquid/vapor, respectively.

Reference