Development of a Tube-Based Elastocaloric Regenerator Loaded in Compression: A Review

In recent years, devices based on the elastocaloric effect (eCE) have emerged as one of the most promising alternatives to vaporcompression cooling and heating systems. After a brief overview of elastocaloric materials and elastocaloric devices developed to date, this paper reviews our recent activities in the development of tube-based elastocaloric regenerators loaded in compression. These include the evaluation of novel elastocaloric thermodynamic cycles, the characterization of the elastocaloric and fatigue behavior of Ni–Ti tubes, the thermo-hydraulic evaluation of a tube-based geometry to be applied as an elastocaloric regenerator, the buckling analysis of Ni–Ti tube in compression, and finally the development, numerical modeling, and testing of a tube-based elastocaloric regenerator in both cooling and heat-pumping modes. The developed regenerator shows a durable operation with more than 300,000 cycles, a maximum temperature span of more than 31 K at zero thermal load, and a heating power of more than 60 W at a temperature span of 10 K using only 13.7 g of elastocaloric material. In addition, further improvements of the tube-based elastocaloric regenerators related to a lower thermal mass of the regenerator’s housing are shown and discussed.