A magnet-based device for active magnetic regenerative refrigeration

Performance analysis of a room temperature rotary magnetic refrigerator for two different gadolinium compounds

“…Table 1 Theoretical results for various operating conditions of the same type of room temperature rotating magnetic refrigerator Qualitative comparison with experimental data reported in Refs. [20,21]. Bold data are those matching experimental results in [20].…”

“…[20,21], where a pure gadolinium alternating device was tested with similar plate geometry (in that case rectangular plates), same MCM mass and cycle time of 2 s. Reported temperature spans are 4 and 7 K, with an MCE ¼ 1.7 K. The reported comparison is only qualitative, since an alternating active magnetic regenerator (AAMR) has a physical behaviour completely different from the rotary, continuous one studied in the present paper.…”

“…Several experimental data are available in literature, those reported in Refs. [20,21] were used as an example. The MCM was pure gadolinium in a 0.8 T magnetic field, and measured heat transfer rate of 37 and 7 W were reported, with global COP of 9 or 2 for a water mass flow rate of 5 or 0.5 g s À1 , respectively.…”

“…The geometry here adopted, very similar to the one used in Refs. [20,21] is probably still too regular to be considered a porous matrix, but has anyway a void fraction (a ¼ 0.091) very low (in particular the same of the experimental set up), which should assure high power densities per unit volume.…”

Innovative design of a magnetocaloric system

“…Future developments are expected in all aspects of magnetic refrigeration to be rapidly forthcoming because the traditional vapor compression technology is asymptotically approaching its technical limitations for additional increases in energy efficiency, and because of environmental concerns, while magnetic refrigeration promises significant improvements in both [4,5]. Several teams in the U.S. [6], the Netherlands [7], Switzerland [8], China [9], Canada [10], Japan [11] and France [12] are working on magnetic cooling, in order to show up refrigerators or heating and air-conditioning applications since magnetic refrigeration has already made the proof-of-principle so attractive that more and more interest is shown all over the world.…”