Drying rate depending on curvature?

[jangheej]

hi all =D
i have a question about evaporation rate depending on curvature.
say a droplet of water is placed on a curved surface- one concave, one convex but with the same radius of curvature.
will the evaporation rate be different?

 

[Bloodthunder]

It's the one with the larger surface area that evaporates faster.

 

[Andy Resnick]

hi all =D
i have a question about evaporation rate depending on curvature.
say a droplet of water is placed on a curved surface- one concave, one convex but with the same radius of curvature.
will the evaporation rate be different?

If the drop radius is less than that of the curved surface and the contact angle is the same for both cases, the drop on a convex surface will have a larger surface area and thus evaporate faster.

 

[jangheej]

If the drop radius is less than that of the curved surface and the contact angle is the same for both cases, the drop on a convex surface will have a larger surface area and thus evaporate faster.

different surface area? why?
the droplet is just resting on the surface (see the image below)

 

[Andy Resnick]

different surface area? why?
the droplet is just resting on the surface (see the image below)

You drew a very special case- perfect non-wetting. In that case, there is hardly any heat flow from the surface to the droplet. And since the surface area is the same for the two cases, the rate of evaporation should be about the same.