I am an electrical engineer and I am not much familiar with fluid mechanics, I am curious to know that Is producing boiling water with low quantity from a fluid with a lower temperature but vast quantity and without electrical energy theoretically impossible ?
That is what a heat-pump does. It is like a fridge in reverse. You can get about 3 or 5 times as much energy from the cold water (which gets colder) as it takes to compress a working fluid and pump it round a circuit and dump its heat into what needs to get hot. Getting from a lot of cold water to boiling water may not give so much advantage as 3 to 5, though, but houses are heated using this principle, even in freezing conditions (getting heat from sub-zero air).
Dear Malcolm White,
Thanks for your answer.
I forgot to mention "without electrical energy" and I just added the constraint in the explanation.
Is it possible whit this constraint?
You will need some kind of energy! One version of doing it without energy is referred to as Maxwell's Demon (also it would be a perpetual motion machine) and is considered impossible under current understandings of quantum mechanics and thermodynamics. You can get the energy by running the cold water down-hill so that it gets kinetic energy and then creating turbulence or friction to turn this into heat, or by turning a turbine that runs a pump to operate the heat-pump. You can use a hydraulic ram to get a small amount of water with a lot of kinetic energy, turn it into heat and repeat in further stages with increasingly hot water (you did say you had a large amount of cold water!). There is probably a better way of doing it than this!
There is a device called "Absorption heat transformer" that could do this trick. Though I until now never completely understood how it is working (job for a physicist, not for an EE engineer), it exists.
BTW: there are 'absorber fridges' working with LPG. "Inverting" the fridge would create a device that could heat the water without electrical energy (though not without any 'external' energy at all).
But I think even the heat transformer will not work without consuming energy other than the fluid's heat. There's "something about entropy" :)
See www.iolitec.de/en/Download-document/966-Absortion-Heat-Transformer.html for example. This needs a temperature difference to operate, and uses a pump - so it is actually a heat pump. The stated or proposed advantage is that it can operate efficiently with temperature differences that are usually considered uneconomic, e.g. 60 degrees.
http://web.ornl.gov/info/reports/1986/3445600641928.pdf This one uses a pump - so is actually a heat pump. Perhaps heat transformer is just an old or another name for a heat pump.
Yes - I've been looking it up, although the one I saw said 'almost' no pumping. But it does need more stuff at an intermediate temperature to make it work than you get back at a slightly higher temperature. It is like the thermal version of a hydraulic ram https://en.wikipedia.org/wiki/Hydraulic_ram - so it could work if there was a low temperature sink to use.
For any of these to work you need somewhere lower for something to go to - either lower height or lower temperature (or lower speed or ....?). If you just have a lot of cold water in one place and nowhere for it or its heat to go then you can't get work from it.
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