The Italian elastocaloric rotary air conditioner: Numerical modelling for optimal design and enhanced energy performances

SUSSTAIN-EL is a rotary elastocaloric device for air conditioning that currently is under development at Heat Transfer Laboratory of University of Naples Federico II within the project SUSSTAINEBLE. Elastocaloric is an eco-compatible technology classifiable as alternative to vapor compression basing on elastocaloric effect, a physical phenomenon visible as a temperature change in a solid-state material due to an adiabatic change of a pilot field. The employment of solid-state materials as refrigerants, given their zero contribution to global warming, allows to consider the technology as ecofriendly. In this paper the two-dimensional numerical model of the elastocaloric rotary device has been introduced. The tool allows to frame the optimal solution for the development of the device. An efficient design allows to overcome and improve the related factors affecting the energy and thermal performances. Next to the thermos-fluid dynamic behavior of the prototype, also the elastocaloric effect manifesting in the elastocaloric refrigerant has been estimated through an accurate numerical model, experimentally validated thanks to the results of the investigation carried out by CNR always within the project SUSSTAINEBLE. Also, the two-dimensional model has been experimentally validated through available data on another experimental elastocaloric device published in open literature. The results of test campaign reveal that 0.3 Hz as working frequency and 6 m s⁻¹ as air flow velocity maximum values of temperature span (21 K) and cooling power (450 W) were registered, whereas 5 is the medium coefficient of performance.