Systems and methods for tiering of heatpipes

Heat-rejecting media comprising:

• a heatpipe structure comprising a plurality of heatpipes, the plurality of heatpipes comprising:
• a generally-cylindrical first pipe having a first cross-sectional area based on a first height and a first lateral width;
• a generally-cylindrical second pipe mechanically coupled to the first pipe having a second cross-sectional area based on a second height and a second lateral width, wherein the second cross-sectional area is less than the first cross-sectional area and the second lateral width is less than the first lateral width;
• and
• a generally-cylindrical third pipe mechanically coupled to the second pipe having a third cross-sectional area based on a third height and a third lateral width, wherein the third cross-sectional area is less than the second cross-sectional area and the third lateral width is less than the second lateral width, such that the second pipe is coupled between the first pipe and the third pipe, and the first pipe, second pipe, and third pipe form a closed plenum;
• and
• a finstack structure comprising a plurality of fins mechanically and thermally coupled to the third pipe.

A method for fabricating a heatpipe structure comprising:

• coupling a generally-cylindrical first pipe having a first cross-sectional area to a generally-cylindrical second pipe, the second pipe having a second cross-sectional area less than the first cross-sectional area;
• coupling a generally-cylindrical third pipe to the second pipe, the third pipe having a third cross-sectional area less than the second cross-sectional area, the coupling such that the second pipe is coupled between the first pipe and the third pipe, and the first pipe, second pipe, and third pipe form a closed plenum;
• and
• mechanically and thermally coupling a finstack structure comprising a plurality of fins to the third pipe.