An international team discovered a method of cooling fibres by twisting them, potentially producing more energy-efficient refrigeration
Spotted: An international team of scientists have found a way to twist fibres to produce a substantial cooling effect. The study could have significant implications for energy-efficient refrigeration, according to the team.
The core principle of the work – that a rubber band heats when stretched and cools when relaxed – has long been known. But to work, it requires a very large stretch. The research showed that other fibres can be twisted to greater effect.
The process is called twistocaloric cooling. The scientists found that if they stretched rubber fibres, twisted them into a “supercoil”, and then released them, they cooled even more. The effect was more pronounced still, if they twisted and stretched at the same time. For instance, rubber fibres cooled by 15.5 degrees Celsius when the first method was used, compared to 16.4 degrees Celsius with the twist and stretch method. Other materials, like nickel-titanium, performed better. The best result was with a bundle of nickel-titanium, which cooled by 20.8 degrees Celsius.
Scientists from the University of Texas, Dallas in the US and China-based Nankai University, led the research, together with other institutes. The team says the findings show there are opportunities to use twistocaloric materials, both large and small-scale. More research is necessary, however.