Description

A long horizontal rod, which is heated at one end, provides an extended surface (pin) for heat transfer measurements.

Thermocouples at regular intervals along the rod allow the surface temperature profile to be measured.

Hardware Description

The rod is manufactured from brass and mounted horizontally with support at both ends positioned to avoid the influence of adjacent surfaces. The rod is coated with a heat-resistant matte black paint, which provides a consistent emissivity close to unity.

It is heated by an electric heating element, which operates at low voltage for increased operator safety and is protected by a thermostat to prevent damage from overheating.

Eight thermocouples are attached to the surface of the rod at equal intervals of 50mm, giving an overall instrumented length of 350mm. Another thermocouple is mounted adjacent to the heated rod to measure the ambient air temperature.

The heated end of the rod is mounted coaxially inside a plastic housing, which provides an air gap and insulates the area occupied by the heater, in order to minimise heat loss and prevent burns to the operator.

The measurements obtained can be compared with a theoretical analysis of thermal conduction along the bar combined with heat loss (heat transferred) to the surroundings by the modes of free convection and radiation simultaneously.