Shape memory alloys (SMA) have attracted increasing interest in recent years as materials suitable for solid state refrigeration. One of the most attractive methods is mechanical deformation to induce the phase transformation and to generate and absorb heat through the elastocaloric effect. NiTi alloy is commercially available in various shapes and sizes, it has excellent elastocaloric properties and, being now marketed in various industrial sectors, is the most suitable for the development of prototype thermal management devices. Different types based on compression or tension of the material have been developed. Our demonstrator uses torsion as the deformation method that presents greater perspectives of fatigue resistance, and the use of tubes allows us to have the liquid inside the tube as a means of transferring the heat generated and/or absorbed.
Solid state refrigeration systems, instead of traditional gas compression-based systems, are environmentally sustainable and subject to wide development perspectives. The research concerns both the study of caloric materials, particularly SMA alloys, and the efficiency of the caloric effect, as well as the design and implementation of PoC. The use of the elastocaloric effect is particularly innovative and useful for its efficiency, simplicity of induction and the possibility of different scales of size operation. The further innovative aspect of our demonstrator is the use of torsion which, even if it does not correspond to a homogeneous deformation of the material and therefore to an efficiency distributed in the heat emission/absorption tube, has clear improvement in terms of use’s fatigue and maintenance of the basic operating parameters, even in the event of breakage. Starting from a PoC, the way is then open for the design and optimization of a prototype device in various directions, both dimensional and in the application sector.