cTech Heatpipe Thermal Solutions: A Heatpipe is a “two phase” heat transfer mechanism with extremely high “effective” thermal conductivity. A thin walled pipe with an internal wick structure allows boiling and condensing to occur within the pipe resulting in heat transfer from the hot end to the cooled end. Small volumes of liquid evaporate at the hot end, even at low temperatures due to the vacuum inside the pipe, and condense on reaching the cooled end, giving up its latent heat. The condensed liquid then wicks it’s way back to the hot end by capillary action and/or gravity and the cycle repeats.