Pruned — On landscape architecture and related fields — ArchivesFuture Plural@pruned — Offshoots — #Chicagos@altchicagoparks@southworkspark
1
Leidenfrost Fountain
It seems that scientists at the University of Oregon have discovered a way to make liquid droplets walk on their own.

Even uphill!

Leidenfrost effect


In the phenomenon called the Leidenfrost effect, or film boiling, liquid droplets on a surface heated above their boiling point form an underlayer of vapor, which suspends them above the surface like a hovercraft. Normally, the droplets would move about erratically. However, Professor Heiner Linke and his colleagues have discovered that if “placed on asymmetrically structured surfaces, such as a piece of brass with periodic, saw-tooth shaped ridges” they would self-propel themselves in one direction. And quite literally using their own steam power.

You can see their movies for yourself.

Leidenfrost effect

Leidenfrost effect

Leidenfrost effect

Leidenfrost effect

Leidenfrost effect

Professor Heiner Linke is not yet certain where the propulsive forces come from, but he has already speculated on how it can be applied: “This method uses heat to pump liquid, and could therefore be used in pumps for coolants, for instance to cool microprocessors. Such a pump would need no additional power (it's run by the heat that needs to be removed anyway), it would have no moving parts, and it wouldn't require a thermostat.”

Of course, I'd like to know if you can construct a landscape feature exploiting this phenomenon. Parks criscrossed by racheted channels heated simply by the Earth or the parking garage underneath, and on these channels, giant film-boiling droplets race past by, indifferent to gravity.

If you turn on the heat, will the Chicago River re-reverses to its original course? Probably not, but I'd like that to see that happen as an annual event.
2 COMMENTS —
  • Anonymous
  • April 4, 2006 at 10:54:00 PM CDT
  • article on leidenfrost effect to do with walking on hot coals, and how he tested it by putting his hand on a red hot stove element.

    Within which is mentioned the famous demonstration Jearl Walker used to do for his students, of plunging his moistened hand into a pot of molten lead. the best picture is in Walker's PDF. more at: pic, mefi, pbs,


Post a Comment —
Comments on posts older than a week are moderated —

—— Newer Post Older Post —— Home
1