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Elastocaloric is a promising cooling technique that offers a solid-state alternative to vapor compression. The elastoCaloric Effect (eCE) refers to the reversible changes in temperature and entropy that occur in Shape Memory Alloy (SMA) when loaded/unloaded by an external mechanical load. The research introduced in this paper compares various Ni–Ti-based SMAs to determine the optimal one to be exploited in an experimental air conditioner. The device can lodge 600 SMA wires in the space stacked by two cylinders concentrically arranged, with inner/outer diameter of 250/280 mm. Tests are performed while the device rotates at variable frequencies ranging from 0.3 Hz to 0.7 Hz. A rotary meshing two-dimensional tool has been developed and used to perform the test campaign under variable working conditions and NiTi-based SMAs. The energy performances are evaluated and (Ni50Mn31.5Ti18.5)99.8B0.2resulted in the most suitable SMA showing 2.13 kW as peak of cooling power (at a cycle frequency of 0.6 Hz and a utilization factor of 0.7) and a maximum COP of 8.35 (at 0.3 Hz and 0.7 as utilization factor). This work demonstrates that the use of the (Ni50Mn31.5Ti18.5)99.8B0.2alloy can enable the device to achieve performances superior to vapor compression-based devices.

This paper presents a numerical study of the elastocaloric effect in NiTi wire using two different configurations in a rotary prototype, analyzed through a 2D model solved via the finite element method. The focus is on the design of the device’s cold and hot channels, comparing two configurations: the obstacle configuration and the cross-configuration. The obstacle configuration includes barriers in the transition area to prevent unwanted mixing between the inlet and outlet air from the cold and hot regenerators, while the cross-configuration features an equidistant arrangement between the inlet and outlet sections to avoid suction phenomena at the outlet sections.

So far, much of the research on the caloric effect has focused on the magnetocaloric effect, which was the first investigated chronologically, in the field of room temperature for about 40 years. Subsequently and especially in the last decade, scientific research has focused on the development of solid-state technologies other than the magnetocaloric one, including the one of interest for this work: elastocaloric technology. This work is part of the “SUSSTAINEBLE” project of the Department of Industrial Engineering at the University Federico II of Naples, aimed at developing the first Italian prototype of an elastocaloric device for environmental conditioning. The prototype is currently in the experimental development phase and its design and construction are dynamically accompanied by a two-dimensional numerical model that fully reproduces its thermo-fluid dynamic operation. The rotary-type prototype consists of 600 Nickel Titanium wires subjected to loading and unloading phases controlled by a properly programmed optical encoder. The thermo-fluidic medium that regulates heat transfer is air. The aim is to characterize the operation of the elastocaloric device using numerical analysis software in order to optimize its geometric, operational, and environmental parameters, to maximize its energy performance in terms of temperature difference, useful thermal power, and coefficient of performance.

The scientific community has been working hard lately to develop fresh, environmentally friendly refrigeration technologies. Those based on solid-state refrigerants are among the Not-In-Kind Refrigeration Technologies that show great promises. The one based on the elastoCaloric Effect is among the most interesting of them. This paper presents the development of a 2D numerical model for a device harnessing the elastocaloric effect with the primary objective of cooling electronic circuits. The study focuses on the intricate interplay between mechanical and thermal aspects, capturing the dynamic behavior of the elastocaloric material in response to cyclic mechanical loading. The numerical model incorporates detailed descriptions of the electronic circuits, accounting for heat dissipation and thermal management. Through simulations, the optimal configuration for efficient cooling is explored, considering various operative conditions and mechanical loading conditions (tensile and bending). The findings contribute to the advancement of elastocaloric cooling technology, offering insights into the design and optimization of devices aimed at enhancing electronic circuit performance through effective thermal control. The results that the most promising configuration is based on bending, a design choice resulting appropriate for cooling the electronic circuits.

•Barocaloric is an emerging cooling technology based on solid-state materials.•Barocaloric is a potential ecofriendly alternative to vapor compression.•A review of the thermodynamical cycles, materials and numerical models is presented.•Future perspectives and lines of research are drawn.

•SUSSTAIN-EL is the name of the first Italian elastocaloric prototype for air conditioning.•The rotary prototype is made of elastocaloric wires crossed by air as heat transfer fluid.•A numerical model to investigate working parameters has been developed.•The model is used to draw a guide map for efficiently design of SUSSTAIN-EL.•The energy performances are numerically estimated and experimentally validated.

•SUSSTAIN-EL will be the first Italian elastocaloric device for cooling.•The prototype is rotary and made of bunches of elastocaloric wires crossed by air as heat transfer fluid.•A numerical model to optimize both geometrical and working parameters has been developed.•The model is a guide in the design steps of the prototype.•Test campaign to optimize the single bunch of elastocaloric elements.