In water drops which are on the cold surface, formed during the freezing pointy tops

Physicists from the Dutch University of Twente have discovered that water drops are on a cold surface, are formed during freezing pointed tops.

Freezing front moves upward in the droplet. The liquid portion is kept constantly at the top of the surface tension forces. Water expands during freezing, but due to the fact that the droplet is attached on the surface, it can not expand in the horizontal direction. As a result, the front of the freezing becomes concave. In the last step of freezing the ice pushes fluid higher and at the end of the drop forms an acute apex. This phenomenon, according to the authors, is easily reproduced, even with ordinary tap water.

Other fluids under similar conditions sharp peak is not formed, since they do not expand upon freezing.



via factroom.ru