Take a hollow spoon, remove the air, put some ammonia in it, weld it shut, and you have an efficient heat pipe. (See link.)

If you encounter some too-hot soup or coffee, just dip the Heat Pipe Spoon in it for a few seconds. The heat will be extracted from the liquid and radiated into the air.

Ideally, the spoon would be constructed of silver, the metal with the highest thermal conductivity. That would make it even more effective.

UPDATE: I did some research, and water as a working fluid would give better performance, with the added benefit of being non-toxic if the Heat Pipe Spoon is broken.

UPDATE2: A couple of improvements to the design might be: (1). A heat guard on the handle end, such as a perforated cylinder that you see on machineguns. This would allow the spoon to be handled without burning your fingers. (2). A valve to prevent or modulate the flow of heat through the spoon. Would also improve usability by allowing the spoon to be more easily handled.
-- AntiQuark, Aug 01 2010

Heat Pipes http://en.wikipedia...gn_and_construction
Wiki page giving detailed explanation of heat pipes. [AntiQuark, Aug 01 2010]

Beverage Heat Exchanger Beverage_20Heat_20Exchanger
Similar idea with electric Peltier coolers. [AntiQuark, Aug 01 2010]

Amazing Discovery! http://s374.photobu...ae0fd7e19af6723.flv
It Seems Plausible in My World... [Grogster, Aug 01 2010]

Selecting a Heat Pipe Fluid http://www.enertron...ect-a-heat-pipe.pdf
PDF describing the properties of different fluids. [AntiQuark, Aug 01 2010]

Why fill it with Ammonia? Water works better.
-- DIYMatt, Aug 01 2010


I think this is better baked by my phase change ice cream scoop, but that is different. I also agree water is better unless you can pressurize so the ammonia does a phase change.
-- MisterQED, Aug 01 2010


Ammonia would be quite effective if a compressor, high pressure receiver, king valve, evaporator, and condenser could be shrunk to a size small enough to fit into a soup spoon. Now it can! See [link]. Bun! [+]
-- Grogster, Aug 01 2010


[Grogster,MisterQED,DIYMatt]: Agreed, I looked around a bit, and water would be a better fluid in this situation. (See link).
-- AntiQuark, Aug 01 2010


NaK.

If you build it, it will explode ...
-- 8th of 7, Aug 01 2010


[8th], Brilliant! We used sodium at the Fast Flux Test Facility (a little 400 megawatt research breeder reactor) for coolant because it didn't slow down neutrons. Indeed, a big BOOM when exposed to water -- but if the soup spoon ever breaks, it would be fun to see it go out with a BANG! Dangerous. Ill-advised. Perfect.
-- Grogster, Aug 01 2010


By the way, have you noticed this post is replete with gems that could be marked-for-tagline?
-- Grogster, Aug 01 2010


Not if the grip were made of non-woven silicate fibre within a rigid silicon nitride sheath, and a heatsink at the end opposite the bowl.

Please, do try to keep up.
-- 8th of 7, Aug 01 2010


Where does the heat go? How does it get radiated by the teaspoon?

I ask because I am pretty certain that heat conduction along the spoon is not the limiting factor.
-- MaxwellBuchanan, Aug 01 2010


When I described my Tea-Cooling Dart, I chose a dart shape because it had large fins out in the air. The water-contact surface area doesn't need to be as big as the air-contact surface, I say. The spoon bowl is good for picking up heat, but you'll need a wide handle to get rid of the heat into the air, and you'd best hope nobody thinks the handle is for picking up the spoon while it is busy radiating heat.
-- baconbrain, Aug 01 2010


[MaxB], my impression was that while the concave surface of the spoon was busily sucking up heat the convex surface at the bottom would be just as busy disposing of the aforementioned heat. To send it up the handle makes no sense 1) because of the "...non-woven silicate fibre within a rigid silicon nitride sheath..." on the handle, and 2) the only time you REALLY need the [soup/gruel/glop] cooled off is when it is heading immediately toward your taste receptors. As long as the nutritious glop is still in the bowl, I would imagine the idea is to KEEP it hot until it is ready to be consumed, so sending it up the handle really doesn't work. Somewhere in transit between the spoon dipping procedure and the slurping procedure, the excess heat has to be dissipated, and quickly, to avoid burning your LOWER lip just as a normal soup spoon would burn your UPPER lip.
-- Grogster, Aug 02 2010


[Grogst], the idea says to dip the spoon into the liquid for a few seconds, and mentions a heat pipe. It sounds to me like a way to cool off a glass or cup of beverage before it is consumed.

I agree with what you are saying about the bowl of the spoon cooling soup, though, big time. I recently found a large plastic spoon in my camping kit, and transferred it into the kitchen (as it is microwavable). It is dangerous to eat hot soup with it, as it doesn't cool a scoop of the stuff as much as a metal spoon when it is blown upon.
-- baconbrain, Aug 02 2010


Good grief, [BaconB] you're right! [AntiQ], can you add a blocking valve onto the distal end of handle to prevent the heat from coming up the pipe as long as the spoon is in the glop?
-- Grogster, Aug 02 2010


[Grogster], Updated!
-- AntiQuark, Aug 02 2010



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