A heat pipe is a device
used to transfer heat from one end
to the other more effective
ly than a rod
of massive metal
It works by a liquid boiling
away at the hot end, and condensating
at the cold end. The condensate
is then re-transferred to the hot end by the means
of a wick
, or simply by gravity
if that is possible.
The phase change
takes a lot of energy
and has the additional benefit
that the hot end can't get any hotter than the boiling point of the liquid in question, as long as the heat pipes specs
are not crossed.
The problem with this design is that it has to be matched to the type of heat source by choosing the appropriate
liquid, boiling point and amount of liquid in the device, as it will work effectively only in a narrow
band of temperature/amount of energy.
In low-range temperatures (30° - 80°C), alcohol
under normal or reduced pressure
is often used. In higher ranges, liquid metals are the medium