The module is composed of 126 couples.
To supply heat energy to the hot side of TE modules, a thermo-
coax electric heater SEI 10/50 is used providing a continuous power
of about 150 W. An aluminium heat sink with fins was mounted on
the cold side of the TE modules. Thermal grease is used to enhance
heat transfer between the surfaces. Two different cooling systems
are tested to maintain a constant temperature on the cold side
[12,13] (an electric air fan or temperature controlled cold water).
Best results were obtained with cold water. Temperature measurements
were made with type K thermocouple 10/100 mm to avoid
heat shunts and were placed in different parts of the modules. The
whole device was enclosed in stone wool for insulation.
The temperatures, tension and current were recorded by using
an Agilent 34970A Data Logger. The measurement system permits
us to obtain a precision of 0.01% for the tension, 0.1% for the current
and of 0.5
C for the temperatures. But, because of the difficulty to
measure a surface temperature accurately, the temperature errors
are evaluated to 1
C