CONDUCTIVITY OF LIQUIDS & GASSES

This experiment has three concentric cylinders. The inner
cylinder contains an electric heater (the heat source). The
test liquid or gas forms a second, thin cylinder around the
heat source. The third cylinder cooled by water surrounds
them both to make a heat sink. The whole assembly is
mounted on a base plate with a clear schematic of the
experiment layout.
Heat passes by conduction from the heat source, through
the test liquid or gas, to the heat sink. Thermocouples
measure the temperature on the inside and outside edges
of the cylinder of test liquid or gas.
The electric heater and thermocouples connect to sockets
on the Heat Transfer experiments base unit, which also
supplies the cold water feed and drain for the heat sink
Caps of thermally-insulating material at the ends of the
cylinders reduce heat loss, but students do an initial
experiment to calibrate the equipment to allow for heat
losses and improve experiment accuracy. One end cap is
removable to allow the unit to be easily cleaned when
changing from one fluid to another.
Students turn on the cooling water and the heater and
measure the temperatures at each side of the test gas or
liquid. They then compare their results with those
predicted from theory for conduction in liquids and gasses.