"How's the temperature son?"

"650 Dad. Speed is 1,200. The Kamchatka volcano field is coming up. We can heat back up to 900, then we shouldn't have to re-heat again until we reach Mt St Helens....after that its just a cool down cruise into SanFran. Hope Mom has that apple pie ready!"

Frank checked the satnav. "Pod, take us onto re-heat ramp K34. How long will a 900 re-heat take?"

The pod's AI responded, "Kamchatka Lava lake 16 is currently moderately active. Pod re-heat to 900 degrees, ventral, estimated at 12 seconds. There is a small queue of pods waiting. Delay to enter lava lake is 40 seconds. Recommend re-heat to 915 degrees if you wish to use Mt St Helens reheat station, as delay to enter Mt St Helens lava dome is currently six minutes."

"Fucking Sunday drivers.." thought Frank. Probably most of the delay at MSH was rent-a-pod weekend trippers from EuropUral, using those boxy VolvoPods. No style those people.

His own Pod was the latest - twenty centimeter thick, tungsten-rich alloy on the ventral surface, the latest in heat shielding aerogel on the front and top. All the comforts inside. The first time he had taken the new pod down the acceleration ramp from it's initial heat-up on Kilauea he had been blown away by its speed and comfort. Much easier to control than earlier models too, with the softest touch of the airbrakes enough to safely guide the skimming white hot pod around any obstruction. "Very nice.", he thought.

He noticed his son had gone a little quiet. It was always the same when the Pod slightly corrected his son's re-heat calculations. He would have to learn to put up with that. Only the advanced AI in these newer pods could make the necessary calculations. And anyway, there was apple pie waiting in SanFran.
-- ConsulFlaminicus, Oct 09 2005

Leidenfrost Effect http://www.physics....rostphenomenon.html
[ConsulFlaminicus, Oct 09 2005]

A .pdf link http://www.wiley.co...idenfrost_essay.pdf
[ConsulFlaminicus, Oct 09 2005]

so the heat source is geothermal ie roads with lava underneath or are you predicting the entire surface of the planet will soon be of skillet temperature from global warming?
-- benfrost, Oct 10 2005


The water is carried by the pod, right? And kept boiling by...? Bun for interesting and unexplored vehicle concept.
-- wagster, Oct 10 2005


I think that the pod is heated, and then skimmed across the water?

Btw, I am lucky enough to see this effect all the time, at the electric arc furnace, and steel casting machine. One comment for those that want to experiment: never put liquid steel on water. The reverse is possible. The former explodes violently.
-- Ling, Oct 10 2005


Since this only works over water, how do you travel over land?
-- Antegrity, Oct 10 2005


It doesn't work over water. You would sink.
-- wagster, Oct 10 2005


Water isn't necessary apparently, what is important is the temperature difference between the two surfaces and that one of the surfaces be capable of 'boiling' - at first I thought this would only be possible in arctic climes, using smooth 'ice highways' , either shaped like a bobsled run (but with a very tiny gradient) or wide, flat expanses allowing for some freedom of movement. A bit of halfbaking though has changed the pods into free roaming vehicles which can travel over any even surface.

The 're-heat' stations are volcanoes or other geothermally active areas of raised elevation - the height of the re-heat stations imparts the initial acceleration to the pods, then they sort of skit along and coast up to the next station (the AI calculates the deceleration precisely so that the pods gently slip onto the tractor platforms that take them into the lava and then retreive them and push the superheated pods off the top of the volcanoes).

All entirely non-feasible of course, as the friction and heat forces would melt the croissant hood ornaments and theres no way I'm driving anything without a croissant hood ornament.

[Ling] //Btw, I am lucky enough to see this effect all the time, at the electric arc furnace// I'm glad you have that connection - us males see it very, very often when we utilise urinals that have cold stainless steel troughs - so 'boys' usually are quite familiar with the Leidenfrost effect.
-- ConsulFlaminicus, Oct 10 2005


I had always assumed those were due to surface tension. The same happens with cold water on cold water in the kitchen sink, sometimes.
-- Ling, Oct 10 2005



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