Twisted Elastic Fibers Could Cool Your Food, Study Finds (sciencemag.org) 24
sciencehabit shares a report from Science Magazine: It sounds crazy: a refrigerator made from a rubber band. But if you stretch one and hold it against your lips, it will be noticeably warmer. Release it, and it cools. This simple "elastocaloric" effect can transfer heat in much the same way as compressing and expanding a fluid refrigerant in a fridge or air conditioner. Now, scientists have created a version that not only stretches the rubber band, but also twists it. It may one day lead to greener cooling technology. As a demonstration, the researchers built a tiny fridge about the size of a ballpoint pen cartridge powered by twisted nickel titanium wires. Using this "twistocaloric" method, they cooled a small volume of water by 8C in a few seconds. Next, the team plans to run the device on a repeating cycle, alternately heating the water (and moving that heat to the outside world) and cooling it (so that it can absorb heat from the interior volume). Coated with temperature-sensitive dyes, the fibers could also serve as strain gauges or mood rings. The study has been published in the journal Science.
Interesting (Score:2)
Seems promising, if the technology can be scaled up beyond the micro-fridge created in the experiment.
Of course, a refrigerant that carries heat energy would still be required to move the heat from inside the box to outside the box; and the material that is ultimately selected for ideal stretching/twisting characteristics would likely have to be easily replaceable, since stretching and relaxing a compound tends to eventually compromise its structural integrity.
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Seems promising, if the technology can be scaled up beyond the micro-fridge created in the experiment.
The next problem is inventing a six-pack that fits into a ballpoint pen sized fridge.
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Me, I would just combine a fridge and the hot water service. You know suck the heat out of the fridge and supply it to the hot water service. You could do a lot of heat balancing that way but the capital cost and maintenance would be quite severe.
Here is something that sounds weird but would really work. When you build houses, make them out of waterproofed concrete and bury them under soil and plant stuff in that soil.
Prior to higher efficiency solar panels and LED lighting, windows used to make some sens
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There are some fairly innovative waste heat reclamation systems that use the heat left in draining grey water (from showers, sinks, washers) to preheat incoming water upstream of the water heater.
Underground homes are certainly well-insulated, and as any prepper will tell you, they have the additional advantage of possible concealment. Depending on where you build them, though, waterproofing can be a nightmare.
Some folks are going to be reluctant to sacrifice the natural light windows provide, and many buil
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Me, I would just combine a fridge and the hot water service. You know suck the heat out of the fridge and supply it to the hot water service. You could do a lot of heat balancing that way but the capital cost and maintenance would be quite severe.
I think some water dispensers which provide both hot and cold water work that way but the results are more like "almost hot" and "slightly cool". Pumping heat across that great of a temperature difference is difficult and unless you have a good use for the concentrated energy on the hot side, it will be bled into the environment at which point the cooling efficiency (COP) becomes even worse and it would have been better to have separate cooling and heating systems. Some industrial processes make good use
This has been done for fun on YouTube many times (Score:2)
If you search through YouTube, you can see many examples where people have done this using rubber bands already. It works to some extent, but not enough to be commercially viable, mostly for fun. Would be interesting to see if this can be scaled up.
Liquid Has Many Advantages (Score:4, Interesting)
It's an interesting thing to study, but is there any application where it stands a chance of outcompeting existing tech?
still waiting for.. (Score:2)
my cheap thermoacoustic fridge promised 30 years ago!
On a side note..i remember back in the early 80's a demonstration on TV of a sub woofer placed at the bottom of a pipe perpendicular to the opening, I forget what sine wave they used, but there was frost building up on on one end do to the sound pressure, there was no pile inside as far as I can tell, just an empty pipe, anyone else see this?
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" there was no pile inside as far as I can tell, just an empty pipe, anyone else see this?"
No.
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They use these style coolers for high speed cutting machinery (I operated many of them). Look up vortex tube.
You don't want one in your house. They're incredibly loud and high pitched.
Rubber bands get weaker with every use. (Score:2)
Just like mattresses.
Also, plastics dry out, and get brittle.
So prepare to replace your fridge every 2-5 years, like your phone or carthel mattress.
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I just put magnetic tape on the back of a tablet.
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I guess if you get one of those Samsung fridges with the giant touchscreen on the front then you probably want to change it every year anyway to keep up with the latest Android updates...
You'll have to replace it every year when it bursts into flames.
Vaccines (Score:2)
No tax dollars on stupid stuff. (Score:2)
"stretch one and hold it against your lips" ? (Score:2)
Right. So it snapped and now I have a fat lip. Why does science have to be so hard?
how is this new (Score:2)
Nitinol (a "memory alloy") and its properties have been known for decades, my buddy in college played with the stuff. Hint, I'm north of half a century old.
1991 - in here you'll see NASA project of fridge using it, just search for nitinol
https://archive.org/stream/NAS... [archive.org]
Interesting phenomenon, maybe not scalable. (Score:2)
As a kid, I was fascinated by the coiling then supercoiling of rubber bands on balsa wood toy airplanes. But, you only got a few flights before the rubber bands broke.
Rubber bands of course are a cheap low performance material, so no surprise. Any device meant to be a durable appliance would use materials that are better suited and engineered for the task. Still one has to wonder realistically what magic material, whether by its chemistry or its physical form, can be stressed or strained, repetitively an
Applied Science video (Score:2)
Dammit! (Score:2)
I noticed this phenomenon more than 30 years ago and wondered if it might be made into a viable refrigeration mechanism. Guess I should have followed up on that...