It can be used to cool or heat the air in a room or to cool or heat liquids. And it looks like something that Q—the tech specialist and gadgeteer in the James Bond films—might have come up with. The prototype device, which has been developed by a research team led by Professors Stefan Seelecke and Andreas Schütze at Saarland University, is able to transfer heat using 'muscles' made from nickel-titanium. Nickel-titanium or nitinol, as it is often known, is a shape-memory material that releases heat to its surroundings when it is mechanically loaded in its superelastic state and absorbs heat from its surroundings when it is unloaded. This unusual property is the reason why nitinol is also referred to as a 'smart alloy' or as 'muscle wire." This effect has been exploited by the Saarbrücken researchers who have developed an environmentally friendly heating and cooling system that is two to three times more efficient than conventional heating and cooling devices.
The researchers say the device also works without the usual refrigerants that damage the environment.
(Score: 0) by Anonymous Coward on Wednesday March 13 2019, @08:27PM (2 children)
They don’t mention it but the process must escape the limits of the Carnot cycle which current refrigeration units approach
https://en.m.wikipedia.org/wiki/Carnot_cycle [wikipedia.org]
(Score: 2) by Megahard on Wednesday March 13 2019, @09:14PM
So maybe it's more like something that other Q [wikipedia.org] would come up with.
(Score: 4, Informative) by c0lo on Wednesday March 13 2019, @09:31PM
Nope. The only difference is the any thermal machine using memory metals work with a solid medium instead of a fluid one.
Besides, this story is news about "antique" technology - nitinol [wikipedia.org] has been used for building heat machines shortly after its discovery; head to the 'Other applications and prototypes' of the linked and see the mentions of 1970-ies tech. (sorry, on mobile, can't deep-link to the place)
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by DannyB on Wednesday March 13 2019, @08:33PM (5 children)
How many times can this nitinol wire bend without breaking?
(if I knew I wouldn't ask)
The lower I set my standards the more accomplishments I have.
(Score: 3, Informative) by c0lo on Wednesday March 13 2019, @09:33PM (4 children)
Far higher than spring steel. However a bitch to machine, because of the very properties that makes it useful.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by DannyB on Wednesday March 13 2019, @09:43PM (1 child)
I'm going to guess that it cannot be 3D printed.
The lower I set my standards the more accomplishments I have.
(Score: 3, Informative) by c0lo on Wednesday March 13 2019, @10:03PM
If you have an e-beam printer with advanced vacuum, you may be able to manufacture [wikipedia.org] the alloy in-place (see the mention of e-beam melting in "boutique" settings). The requirement of homogeneity of the crystal structure for the desired properties may preclude (or make it very time consuming) the localized heating.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Interesting) by mhajicek on Thursday March 14 2019, @05:09AM (1 child)
Actually many steels have a "fatigue limit" of stress, under which the sample does not fatigue and will last indefinitely.
The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
(Score: 2) by c0lo on Thursday March 14 2019, @01:16PM
Pretty much this case too.
Except that the memory metals (or at least nitinol) work better in a large (mono?) crystal status, with a crystalline structure [wikipedia.org] able to accommodate to huge deformations without crystal fractures.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Thursday March 14 2019, @04:04AM
"the usual refrigerants that damage the environment"
Stay away from the usual suspects which were designed to take your money and damage the environment at the same time. First they gave us R12, which causes great damage to the environment. Then they designed the most useless (as a refrigerant) gas R134 that causes great damage to the environment. And then changed that with slightly less useless refrigerants. So that older equipment will have to be replaced every few years (planned obsolescence), making them much more money than they would have.
All this was done while better, natural refrigerants that barely cause any damage to the environment exist. Think R290, R600a etc. They are Propane and Iso-butane. Very efficient, safe and environmentally friendly.
(Score: 2) by MichaelDavidCrawford on Thursday March 14 2019, @11:55AM
Why are not residential homes required by building codes to come with hookups for external refrigerator cooling grills?
It's harder to cool something by one degree than it is to heat it by one degree. Thus to chill your bottle of Dasani makes the air in your home twice as hot as you Dasani is cold.
Further: Leo Szilard and Albert Einstein invented the Einstein-Szilard Refrigerator in response to the cruel tragedy of an entire family perishing of Ammonia poisoning when their refrigerator leaked. While the Einstein-Szilard does use Ammonia, as it has no moving parts it has no mechanical seals. Any competent welder could thus build an E-S that will last until the end of Time.
While arguably less efficient than electrically-driven refrigerant pumps, the heat source for the Einstein-Szilard could be flat black copper panels on one's roof with copper coils soldered to them, with the sink being on the north side of one's home or in warm climes, buried a modest depth underground.
(Deep underground is hot due to radioisotopic decay below, with the effective insulation of the soil above.)
Yes I Have No Bananas. [gofundme.com]