Overview of Existing Magnetocaloric Prototype Devices - Magnetocaloric Energy Conversion: From Theory to Applications - page 305

Table 7.24 Second rotary magnetic prototype from Cooltech Applications
Name and address of institute Cooltech Applications-5 Impasse Antoine IMBS

67810 HOLTZHEIM-France

Name of contact person/email Christian Muller/[e-mail]

Year of production 2014

Type Rotary, 2 stages

Maximum frequency 6 Hz

Maximum cooling power >300 W

Maximum temperature span 38 K

Type of AMR Parallel plates

MC material(s) Gd and Gd Er/La Fe Si

- - -

Type of magnets Permanent Nd - Fe - B, B max = 1.17 T

approximately 3 bar. The two AMR beds were lled with Gd spheres of 0.3 mm in

diameter. The total mass of both AMRs was 110 g. The upgraded prototype could
then achieve 29 K of no-load temperature span. Operating at a frequency of 1.4 Hz,
the device could produce 454.5 W kg − 1 of speci c cooling power at a temperature

span of 2.5 K. The COP under these operating conditions was 1.6.
The second Canadian prototype was also built at the University of Victoria and
presented in 2014 by Arnold et al. [ 57 ]. This was a second-generation prototype,
which was an upgrade of the 2009 version [ 55 , 56 ]. A special novelty was the
implementation of a triple Halbach magnet assembly. Such a triple Halbach magnet
array consisted of three concentric cylinders. The inner cylinder was stationary,
while the intermediate and outer ones were rotating in the opposite directions. The
opposite rotation of the outer cylinders was important to create a sinusoidal mag-
netic eld wave form with a stationary eld direction. Such a magnet assembly had