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2.15.Prompt splash (left) was documented with heptane droplet on a
glass surface with an impact velocity of 9.8m/s, while corona splash
(right) was observed with an alcohol drop, reported by Pan et al. [103]. 26
2.16.Snowflake photos by Wilson Bentley circa 1902. Bentley is one of
the first known photographers of snowflakes. He perfected a process
of catching flakes on black velvet in such a way that their images
could be captured before they either melted or sublimated. These
techniques used by Bentley to photograph snowflakes are essentially
the same as used today. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.17.At an ambient pressure of 1 bar, liquid water exhibits in a number of
forms. Homogeneous nucleation can be avoided by hyperquenching
liquid water at extremely high cooling rates ≧1 × 10 5 K/s to temperatures
below 100 K [24]. This procedure results in an amorphous
form of water. When glassy water is reheated, it undergoes a glass
transition at about 130 K. The region between T f and T x is called
“no man’land” because it is not accessible on experimental time scale
due to rapid crystallization of ice in this temperature range [93]. . . . 30
2.18.Location of the ice /water interface calculated by the one-phase Stefan
problem. The substrate temperature is taken as −20 ◦ C. . . . . . . 35
2.19.Location of the ice/supercooled water interface calculated by the
Stefan problem for the supercooled liquid. The initial temperature
of the supercooled water is −10 ◦ C. . . . . . . . . . . . . . . . . . . . . . 37
2.20.Fraction of solidification at different supercooling. . . . . . . . . . . . . 38
2.21.Applying a sinuous perturbation on the ice/water interface, designated
by the solid curve, the temperature field, denoted by the
dashed curves, becomes uneven. The resultant temperature gradient,
represented by the spacings between the isothermal curves,
manifests the stable nature of solidification without supercooling,
shown on the left, and the intrinsic instability of solidification in the
supercooled liquid, shown on the right. . . . . . . . . . . . . . . . . . . 39
2.22.The growth rate of the free ice dendrite, both the theoretical prediction
and the experimental measurement, is shown on the left.
The morphologies of the ice dendrite formed by water of various
supercooling are shown on the right: (a) −0.3 ◦ C, (b) −1 ◦ C, (c)
−2 ◦ C, (d) −4 ◦ C, (e) −7 ◦ C. These data were reported by Shibkov
et al. [135, 137]. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
242 List of Figures