Elastocaloric effect

Context :

  • Recently researchers from multiple universities, including Nankai University in China, have found that the elastocaloric effect, if harnessed, may be able to do away with the need of fluid refrigerants used in fridges and air-conditioners.

About elastocaloric effect

  • When rubbers bands are twisted and untwisted, it produces a cooling effect. This is called the “elastocaloric” effect

About the Research

  • In the elastocaloric effect, the transfer of heat works much the same way as when fluid refrigerants are compressed and expanded.
  • When a rubber band is stretched, it absorbs heat from its environment, and when it is released, it gradually cools down.
  • In order to figure out how the twisting mechanism might be able to enable a fridge, the researchers compared the cooling power of rubber fibres, nylon and polyethylene fishing lines and nickel-titanium wires.
  • They observed high cooling from twist changes in twisted, coiled and supercoiled fibres.
  • The level of efficiency of the heat exchange in rubber bands “is comparable to that of standard refrigerants and twice as high as stretching the same materials without twisting”.
  • To demonstrate this setup, the researchers developed a fridge the size of a ballpoint pen cartridge that was able to bring down the temperature of a small volume of water by 8°C in a few seconds. They suggested that their findings may lead to the development of greener, higher-efficiency and low-cost cooling technology.