An Index of the Various Types of Heat Pipes
Standard Heat Pipes
These act as a thermal superconductor (typically copper-water in terrestrial applications or for box-level space cooling, and aluminum-ammonia (CCHPs) in radiator designs in space applications).
Annular Heat Pipes
These heat pipes have an inner cavity and are highly isothermal.
Variable Conductance Heat Pipes (VCHPs)
These have a non-condensable gas loading to help maintain the evaporator temperature under changing conditions.
Pressure Controlled Heat Pipes
A form of VCHP where the reservoir size or gas loading can be changed.
Vapor Chambers
These allow heat flux transformation, and heat spreading in two dimensions.
HiK™ Plates
These are thermally enhanced conduction cards or plates. Embedding heat pipes greatly improves the effective thermal conductivity to 500-1200 W/m K.
Heat Pipe Heat Exchangers
Energy recovery systems for commercial buildings, contributing to carbon emission reduction efforts.
Diode Heat Pipes
A diode heat pipe is used when it is necessary to prevent heat flow in the reverse direction.
Cyrogenic Heat Pipes
Specialized passive thermal management devices designed to transfer heat efficiently at low temperatures, typically below -150°C (-238°F).
Loop Thermosyphons
Gravity-aided thermosyphon variant with different flow paths for the vapor and liquid.
Rotating Heat Pipes
Where the centrifugal forces generated in a rotating system return the fluid, rather than relying on a wick.
Loop Heat Pipes
These are passive, two-phase heat transport devices.
Pulsating Heat Pipes
Internal pressure pulsations that transfer the liquid and vapor slug within mini/micro, serpentine channels.
Heat Pipe Loops
This is a Heat Pipe variant with wick only in the evaporator, allowing operation over longer lengths.
