Frazil Nucleation Mechanisms

Abstract Previously the author had suggested that frazil nucleation occurs by a mechanism analogous to spinodal decomposition, aided by turbulence. After further study the following points are made: (1) No critical point exists between solid and liquid; this rules out true spinodal decomposition. (2...

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Bibliographic Details
Published in:Journal of Glaciology
Main Author: Hanley, Thomas O'D.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1978
Subjects:
Online Access:http://dx.doi.org/10.1017/s0022143000033700
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000033700
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Summary:Abstract Previously the author had suggested that frazil nucleation occurs by a mechanism analogous to spinodal decomposition, aided by turbulence. After further study the following points are made: (1) No critical point exists between solid and liquid; this rules out true spinodal decomposition. (2) Pure water can be supercooled to -40°C; at -40°C the theoretical energy barrier to nucleation is about 10 -19 J. Frazil forms after supercooling less than 0.1 deg; at this temperature the theoretical energy barrier is about 10 -14 J. (3) Theory shows that turbulence increases the energy barrier. (4) Turbulence may aid dissipation of heat of solidification, but not sufficiently to account for observed frazil formation at small supercoolings. (5) The author's evidence that frazil can begin to form at supercoolings as small as 0.02 deg suggests that no nucleus except ice itself can account for "heterogeneous" nucleation of frazil.