A method and an apparatus for the efficient transfer of heat utilizing
micro heat pipes that include a cellular foam or interconnected
cellular/truss network having hollow ligaments. A predetermined fraction
of the internal volume of the hollow ligaments is filled with a carefully
chosen working fluid, and the ends of the hollow ligaments are sealed. In
operation, the working fluid evaporates in the region of high heat flux
and condenses in regions of lower temperature, resulting in the transfer
or redistribution of the fluid's latent heat of vaporization. For open
cell foams and interconnected networks, a second fluid flowing through
the open cells, separate from the working fluid but also in thermal
contact with the hollow ligaments, assists in the transfer of heat from
the foam and networks.