Environmental Engineering Reference
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Fig. 10.9 Schematic
presentation of the solid
cooling line
Solid-State Cooling Line
The concept of a solid-state cooling line was presented by Karmanenko et al. in
2007 [
51
]. A schematic presentation of the device can be seen in Fig.
10.9
. The
device consists of a total of
ve elements, i.e. two electrocaloric elements and three
heat conductors, and is constructed in a similar way to the cooling-bridge device.
However, the cooling-line device does not apply thermal diodes. Its working
principle is based on the unsymmetrical pattern of an applied electric
eld and is
explained in detail in Es
kov et al. [
52
]. With a 1D numerical model it was pre-
dicted that the device would be able to achieve a temperature span of 25 K between
the heat sink and the heat source at the operating frequency (the number of ther-
modynamic cycles per unit of time) of 3 Hz. However, the presented concept was
not experimentally tested.
'
10.1.3.2 Electrocaloric Cooling Devices: First Prototypes
In 1992 Sinyavsky and Brodyansky [
45
] presented the
rst concept of an elect-
rocaloric cooling device. The electrocaloric material used was a PbSc
0.5
T
a0.5
O
3
(PST) bulk ceramic in the form of plates with dimensions of 20
0.3 mm
3
.
The plates were positioned on top of each other and copper wires were installed
between the plates to create a gap for the
×
10
×
ow. Furthermore, the wires served
as a conductive material for the electrical charge. From the above description it is
obvious that the device was actually based on an active electrocaloric heat regen-
erator. The total length of one regenerator was 55 mm with a cross-section of
10
fl
uid
fl
5mm
2
and had a mass of 35 g. Two regenerators in parallel were inserted into
a housing, as can be seen in Fig.
10.10
. On one end of the regenerator, a hot heat
×
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