Given the materials and chemicals available to the ancients (like the Greeks or Romans), could they have made a working refrigerator?
My feeling is that if they had ammonia, they could have.
Are you talking modern fridge with compressor, expansion tubes, cooling grid,electric fan, etc? If so I’d say no.
Sure they had the materials, but not the know-how or the technology to make the metal or electrical components.
JMHO
They didn’t know how to make an eletrical motor - so no, they couldn’t have.
They could probably build something that took advantage of the compression/relaxation cycle to lower temperature somewhat – you know, build a piston/cylinder and compress the gas inside, cool the whole thing, then let the gas exapand so that it cools, taking up heat from the surroundings. But I don’t think it would be practical as a refrigerator . It wouldn’t lower the temperature much. IIRC, the specifications that pistons and cylinders could be built to without allowing leaks wasn’t very good even into the early 18th century. (According to James Burke’s “Day the Universe Changed”, it was one of the things that retarded development of a good steam engine). Then you’d need some sort of medium to convey the heat around (I don’t think you’d need ammonia – early refrigerators used brine). I suspect it’d been just a philosophical curiousity, if you could get it to work at all. Probably slaver-operated, too.
Easier just to haul snow down from the mountains (as the Romans did), or store sawed-up ice blocks in a barn full of sawdust.
You do not need an electric motor to power the compressor. Any motor, including a pair of oxen, will do. Nevertheless building the compressor and other components was out of their capacity. And, the main thing the lacked is knowledge. They did not have the basic understanding of how a heat pump works, about heat, gases, etc. This would preclude them from inventing or building a compressor heat pump or an absorbtion heat pump (which is simpler and easier to build).
Sure. They probably built mine:
http://boards.straightdope.com/sdmb/showthread.php?threadid=200664
bardos
The Mesapotamians did know how to make ice-makers, using venturi tubes to increase the effect of the wind.
It doesn’t take too much further imagination to hook up bellows and hoses to maintain a steady air flow.
This isn’t a “reefer” per se, but it would do the same job…
Trinopus
Trinopus, can you provide a cite for the mesapotamian ice-maker? I’d sure like to see how that works, maybe it’s something I could make while camping? Assuming the winds were right or whatever.