Dependence of Freezing Temperature of Supercooled Water Drops on Rate of Cooling

The freezing of individual droplets of very pure supercooled water, ranging in diameter from 5 to 120 μ m, has been photographed and measured as they fall through a vertical temperature gradient established in cold, purified helium, air and other gases. From measurements made on a few hundreds of droplets of the same size, it is possible to deduce the median (or mean) freezing temperature of the group and the statistical spread about the mean temperature. When the ‘observed’ freezing temperatures are corrected for the thermal inertia of the falling droplets and adjusted to a standard rate of cooling, they are in good agreement with earlier work in which the droplets were cooled in a liquid supporting medium. The observed variation of freezing temperature with droplet diameter may be satisfactorily interpreted in terms of the theory of homogeneous nucleation of supercooled water if the specific surface free energy of the crystal/liquid interface is taken to be 20 erg cm -2 between —35 and —40°C. The experimental results are also consistent with, and offer additional support for, the recent Némethy-Scheraga statistical thermodynamical treatment of the ‘flickering-cluster’ model of liquid water.

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Supercooled Water Drops Do Not Freeze During Impact on Hybrid Janus Particle-Based Surfaces

Chemistry of Materials ◽

10.1021/acs.chemmater.8b03183 ◽

2018 ◽

Vol 31 (1) ◽

pp. 112-123 ◽

Cited By ~ 9

Author(s):

Madeleine Schwarzer ◽

Thomas Otto ◽

Markus Schremb ◽

Claudia Marschelke ◽

Hisaschi T. Tee ◽

...

Keyword(s):

Supercooled Water ◽

Janus Particle ◽

Water Drops

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Atmospheric Electrical Effects Resulting from the Collision of Supercooled Water Drops and Hail

Physics of Ice ◽

10.1007/978-1-4899-5573-9_52 ◽

1969 ◽

pp. 594-602 ◽

Cited By ~ 8

Author(s):

E. J. Workman

Keyword(s):

Supercooled Water ◽

Water Drops

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Comment on evidence for surface-initiated homogenous nucleation

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-3-3361-2003 ◽

2003 ◽

Vol 3 (4) ◽

pp. 3361-3372 ◽

Cited By ~ 2

Author(s):

J. E. Kay ◽

V. Tsemekhman ◽

B. Larson ◽

M. Baker ◽

B. Swanson

Keyword(s):

Laboratory Experiments ◽

Drop Size ◽

Supercooled Water ◽

Ice Nucleation ◽

Surface Nucleation ◽

Embryo Formation ◽

Homogenous Nucleation ◽

Atmospheric Data ◽

Water Drops

Abstract. We investigate theoretical, laboratory, and atmospheric evidence for a recently proposed hypothesis: homogenous ice nucleation occurs at the surface, not in the volume, of supercooled water drops. Using existing thermodynamic arguments, laboratory experiments, and atmospheric data, we conclude that ice embryo formation at the surface cannot be confirmed or disregarded. Ice nucleation rates measured as a function of drop size in an air ambient could help distinguish between volume and surface nucleation rates.

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Comment on evidence for surface-initiated homogeneous nucleation

Atmospheric Chemistry and Physics ◽

10.5194/acp-3-1439-2003 ◽

2003 ◽

Vol 3 (5) ◽

pp. 1439-1443 ◽

Cited By ~ 28

Author(s):

J. E. Kay ◽

V. Tsemekhman ◽

B. Larson ◽

M. Baker ◽

B. Swanson

Keyword(s):

Homogeneous Nucleation ◽

Laboratory Experiments ◽

Drop Size ◽

Supercooled Water ◽

Ice Nucleation ◽

Surface Nucleation ◽

Embryo Formation ◽

Atmospheric Data ◽

Water Drops

Abstract. We investigate theoretical, laboratory, and atmospheric evidence for a recently proposed hypothesis: homogeneous ice nucleation initiates at the surface, not in the volume, of supercooled water drops. Using existing thermodynamic arguments, laboratory experiments, and atmospheric data, we conclude that ice embryo formation at the surface cannot be confirmed or disregarded. Ice nucleation rates measured as a function of drop size in an air ambient could help distinguish between volume and surface nucleation rates.

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Growth Modes of Ice Crystals in Supercooled Water and Aqueous Solutions

Journal of Glaciology ◽

10.1017/s0022143000019924 ◽

1967 ◽

Vol 6 (47) ◽

pp. 651-662 ◽

Cited By ~ 19

Author(s):

H. R. Pruppacher

Keyword(s):

Aqueous Solutions ◽

Tube Wall ◽

Pure Water ◽

Supercooled Water ◽

Seed Crystal ◽

Ice Crystals ◽

Tube Axis ◽

Growth Modes ◽

Water Drops ◽

Large Water

The growth modes of ice crystals in supercooled water and various aqueous solutions were studied at different supercoolings by a motion-picture technique. ln pure water contained in plastic capillary tubes, ice dendrites formed which at supercoolings between 1 and 4°C. grew parallel to the tube axis. At supercoolings larger than 4°C. the direction of growth was inclined to the tube axis such that the dendrites hit the tube wall and afterwards proceeded growing in a new direction. As a result it appeared that the ice crystals grew in a zig-zag or screw fashion. This growth mode became enhanced when the supercooling was increased or salts were dissolved in the water. In large water drops, ice dendrites formed which at supercoolings smaller than 1°C. were co-planar with the seed crystal and between 1° and 5°C. split into two dendritic segments. At supercoolings larger than 5°C. multiple splitting of the seed crystal was observed and this became strongly enhanced when salts were dissolved in the water. Tentative explanations for these results are given.

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