Using air as an energy transfer fluid in a refrigerator is not very effective, due to its low specific heat.

A liquid which is thermally conductive and has a high specifc heat would be better.

Brine would be cheap and fairly safe, but might flavour some foods or damage them unless they were hermetically sealed.

The best option seems to be an insulated cabinet with a large tank of mercury in the base, in (on) which the items float. The absorber of a conventional gas-compression heatpump is immersed in the mercury, suitably protected from attack (since many metals, particularly aluminium, are susceptible to solvation by mercury). There is a linear induction drive to ensure that the mercury slowly circulates; it could be done with a mechanical stirrer but linear induction motors are not only silent but way cooler.

Being an excellent thermal conductor, and intrinsically able to adapt its contact area to any object placed in it, mercury will be much more efficient at removing heat from foodstuffs compared to air or any other gas.

Since mercury doesn't "wet" things particularly well, and has a negative meniscus, a quick shake is all that's needed to return the mercury to the pool on removing an item.

What could possibly go wrong ?
-- 8th of 7, Jan 22 2016

This is undoubtlessly an interesting idea.
-- MaxwellBuchanan, Jan 22 2016


So one would have to go fishing in the chilled mercury vat for the last bottle of beer. Instead, would a fine spray of mercury up and onto shelved fridge items be as efficient? Gravity would pull it back down to the vat.
-- whatrock, Jan 22 2016


// So one would have to go fishing in the chilled mercury vat for the last bottle of beer. //

No, because the bottle would float on the surface. Only 10% or so would be submerged.

Think of it as a sort of surreal apple-bobbing.
-- 8th of 7, Jan 22 2016


I can think of a few problems that will need to be solved. Firstly, there is a glaring health hazard, this is just one shelf, down at the bottom, which will require a quite unacceptable amount of bending. I recommend several tray-like shelves with a few centimetres of mercury circulating constantly, the greatly increased surface area can only bring benefits.

Next up is the shocking omission of a freezer. Metallic mercury freezes at -39 ish, so there's absolutely no reason not to employ the same system there.

The surface of the metallic mercury will attract considerable condensation, some form of ventillation/frost free system will have to be included. Again, forcing a little heated air over the surface of the mercury and venting it outside of the refrigerator can't hurt. I would also like to recommend the addition of a little thimerosal or HgCl2 to the mix, because although metallic mercury is an excellent anti microbial, if there are any pockets of water, some bugs will find a way, best to head them off at the pass.

The antimicrobial angle would be an excellent sales pitch for the health nuts out there....
-- bs0u0155, Jan 22 2016


// Think of it as a sort of surreal apple-bobbing //

[+]
-- whatrock, Jan 22 2016


I want that freezer. Get some aluminum ice cube trays and you'll have ice very rapidly.
-- scad mientist, Jan 22 2016


//Get some aluminum ice cube trays and you'll have ice very rapidly/

But no tray.
-- bs0u0155, Jan 22 2016


// But no tray. // Well there is that. I see you published the proper way to use mercury for ice making.

I guess that's why 8th was using bottles with steel caps rather than aluminum cans of beer.
-- scad mientist, Jan 22 2016



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