TABLE OF CONTENTS The variety of heat pipes, in terms of their geometry, function and/or the methods used to transport the liquid from the condenser to the evaporator, is great. Some types of heat pipe have become less popular over the decades or have ceased to be regarded as special , for example flat plate heat pipes and vapour chambers (see Chapters 5 and 8 for examples of the latter types). Other types have seen a reawakening of interest, brought about by demands for increasing miniaturisation and the need to enhance performance, in particular liquid return flow rates. The use of electrokinetic forces is one technique in which the wheel has gone full circle .
Where heat pipe types have been omitted from the discussion in this Chapter, but were present in earlier editions, some suggestions for further reading are retained in the Bibliography section in the Appendices.
The following types will be described below:
Variable conductance heat pipes
Thermal diodes
Pulsating (oscillating) heat pipes
Loop heat pipes (LHPs) and capillary pumped loops (CPLs)
Micro-heat pipes
Use of electrokinetic forces
Rotating heat pipes
Miscellaneous types sorption heat pipe (SHP); magnetic fluid heat pipes
The variable conductance heat pipe (VCHP), sometimes called in a specific variant the gas-controlled or gas-loaded heat pipe, has a unique feature that sets it apart from other types of heat pipe. This is its ability to maintain a device mounted at the evaporator at a near constant temperature, independent of the amount of power...
