Flat heat pipes produce a surface that has a relatively uniform temperature distribution and large surface area. These would be useful in the case where one needs to radiate heat uniformly instead of from a point source. The use of flat plates as wall components could be one possible application for heat pipe technology in the house. Thermal Switches Thermal switches in a heat pipe serve to prevent the pipe from working in certain cases. This can be accomplished by introducing a blockage, made possible in a variety of different ways.
Thermal diodes allow the heat pipe to only work in one direction.
In one example of a heat diode, if the location of the condenser and evaporator switch, the liquid becomes trapped in a reservoir whose wicks are not connected to the rest of the pipe. This makes it so that the liquid will not be able to travel down the length of the heat pipe until the condenser and evaporator switch again to heat the liquid to the gaseous phase so it can flow down the pipe once more. Another example of a thermal diode is when there is excess liquid in a reservoir within the heat pipe. When the evaporator and condenser are switched, the liquid in the reservoir becomes a vapor and condenses on the condenser. This large amount of fluid prevents any vapor from condensing at the other end of the heat pipe and therefore will only allow heat transfer in one direction.