Patent ID: 7115227

Claim:
A heat pipe assembly, under vacuum and having a working substance charged therein, comprising: an evaporator adapted to evaporate the working substance and having a closed leading end; a heat exchanging condenser being in fluid flow communication with the evaporator, the condenser being adapted to condense vaporized working substance received from the evaporator and having a reservoir located at a higher elevation than the evaporator for collecting liquid working substance therein; a discrete, impermeable liquid return passage permitting the flow, by gravity, of the liquid working substance from the reservoir to the evaporator; the liquid return passage extending through the evaporator and terminating near the closed leading end thereof; and a flow modifier positioned within the evaporator, causing swirling working substance flow in the evaporator; whereby the flow modifier ensures that un-vaporized liquid entrained with evaporated working substance is propelled against inner surfaces of the evaporator by centrifugal force to ensure liquid coverage of the inner surfaces, thereby delaying onset of film boiling.