exchangers. Although the basic structure of a thermoelectric refrigerator is essentially
the same, their configurations may differ significantly depending on the heat
exchangers employed. In this study, the following three prototypes were constructed/
acquired and investigated.
2.1. Heat exchangers with forced convection (TER-1)
In order to facilitate a comparative study, the compressor of a conventional
refrigerator (115 l) was replaced with Peltier modules and two heat-exchangers as
shown in Fig. 1. The CP2-127 Peltier modules employed have a nominal maximum
pumping capacity of 120 W and were manufactured by MELCOR, USA. The heat
exchangers were made from aluminium with bonded fins. The overall dimensions for
the inside and outside heat-exchangers were 100 mm · 100 mm · 30 mm with 24 fins
and 200 mm · 150 mm · 70 mm with 33 fins, respectively. The dimensions of the fins
on the outside heat-exchanger were 200 mm · 60 mm · 1 mm and that on the inside
100 mm · 20 mm · 1 mm. Heat transfer between the aluminium heat-exchangers
and their surroundings (inside the cabinet and ambient) was assisted by forced airconvection
provided by a brushless d.c. fan (3W) attached to the inside and two
to the outside heat exchangers.
2.2. Forced convection at the cold side and liquid circulation at the hot side (TER-2)
Typical dimensions of a commercially-available Peltier module, which is suitable
for domestic refrigeration, are 40 mm · 40 mm · 5 mm. The heat dissipated from the
hot side ranges from 50 to 150 W. This gives a maximum heat-flux of around 10 W/