Environmental Engineering Reference
In-Depth Information
Only materials for which the data regarding their magnetic entropy change and
adiabatic temperature change were available are shown. In this manner the maxi-
mum speci
c
lowing equation:
c cooling energy q
R
;
max
can also be given. The maximum speci
q
R
;
max
¼
ð
2T
R
þ
D
T
ad
Þ
D
s
M
ð
2
:
1
Þ
2
where for the examples in Table
2.1
T
R
is the Curie temperature T
C
with the
corresponding magnetic entropy change
D
s
M
and adiabatic temperature change
T
ad
. As is clear from Table
2.1
different MCMs have different Curie temperatures.
In this manner, the parameter q
R
;
max
could be signi
D
cant when designing layered
AMRs. For example, when designing a magnetic refrigerator that would operate at
a certain temperature span it would make sense to choose the material at the cold
end of the AMR with the highest maximum speci
c cooling energy q
R
;
max
.
References
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é
nom
é
ne magn
é
tocalorique. J Phys (Paris) 7:103
109
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é
nom
é
ne magn
é
tocalorique. Comptes Rendus
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-
354
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ë
rcitivkraft.
Ann Phys (Leipzig) 249:141
-
164
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1870
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2
(SO
4
)
3
·
H
2
O. Phys Rev 43:768
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