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The Leidenfrost effect has been observed for liquid droplets, which take longer to evaporate because of the vapor layer formed below it. Has it been observed for other phase transition? (ice to water where the ice is separated by a layer of water.) Can someone theoretically prove or disprove the existence of Leidenfrost effect for other phase transitions?

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  • $\begingroup$ I think you would just get a Leidenfrost effect by proxy, where, if you drop an ice cube into a hot pan, you have a thin water layer (just by bringing the ice cube into ambient temperature $T \approx 20^°$ C that then evaporates and forms a vapor layer. Whether or not this layer can hold ice cubes of a certain mass I cannot say. $\endgroup$
    – John Doe
    Jan 10, 2017 at 18:03
  • $\begingroup$ The vapor phase will be very little at around 20 deg wont it? The main phases present will be a layer of liquid water below the ice cube. Should'nt further melting be delayed till the liquid layer disperses or it transmits sufficinet amount of heat to further melt the ice. $\endgroup$
    – Lelouch
    Jan 10, 2017 at 18:11
  • $\begingroup$ Oh, I meant that taking the ice cube out of the freezer will already produce a thin liquid layer, not a vapor layer. When you drop the ice cube into the pan, this liquid layer builds up further and evaporates at the same time. But the transition rates and how the cube "squeezes out" the liquid under itself...pretty difficult to guess or model I'd say. It would be pretty interesting to go out (since it's winter in the Northern hemisphere) and do an experiment where the ice cube will only be melted by the pan. $\endgroup$
    – John Doe
    Jan 10, 2017 at 18:16
  • $\begingroup$ I get that, but i would like to know whether this effect actually occurs in this case as well. Thanks $\endgroup$
    – Lelouch
    Jan 11, 2017 at 3:24

1 Answer 1

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Alright, I did a little bit of googling, and found two quite interesting articles on the subject. Since you originally asked for a Leidenfrost effect in "...other phase transitions.", I think these examples will be sufficient.

Phys. Rev. Letters has a paper on modeling the Leidenfrost effet for granular materials, glass beads in this case (accessing this from my University network, not sure if it is behind a paywall). The gist is that you can model a Leidenfrost effect by vibrating a shaker fast enough to achieve a supporting layer of very fast, diluted ("gas-like") beads that support a layer of beads that are densely hexagonally packed (like a crystal).

However, I find this review here much more interesting. Figure 1c in particular shows a piece of dry ice (i.e., solid CO$_2$) hovering on a thin sheet of sublimated CO$_2$ gas. (Hope it's ok to use this image here.)

Figure from the second linked paper (is this OK for copyright reasons mods?

So, the answer to your question is yes, there is a Leidenfrost effect for other phase transitions than liquid-gas, and also for other materials than water. The follow-up question of whether this can happen to ordinary water ice is then, I think, answered by the phase transition diagram (from Wikipedia)

Phase transition diagram for CO2 and H2O

So we just need to cross directly from the ice regime to the gas regime, which can happen below the triple point of water ($0.01^°$ C, $611.657$ Pa $\approx$ 0.6 percent of atmospheric pressure), so you'd need a pretty good vacuum to achieve that (so long, dreams of just firing up a pan outside on a Bunsen burner to test it out).

Hopefully this is sufficient enough for an answer :) cheers!

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