Patent ID: 7303002

Claim:
A heat-transfer assembly comprising: a heat-transfer tube having opposite ends, opposite top and bottom panels extending between the ends and opposite sides joining the top and bottom panels; a fin structure housed in the heat-transfer tube and being formed from a plate corrugated to define a plurality of small passages, extending between the opposite ends of the heat-transfer tube, each of the passages having opposite side walls defined by the fin structure, a first transverse wall defined by the fin structure and extending between the side walls of the respective passage and a second transverse wall defined by one of the top and bottom panels of the heat-transfer tube and extending between the side walls of the respective passage, at least one structure for improving heat-transfer, the structure being selected from the group consisting of: notches formed through the side walls of the passages, through holes formed through the side walls of the passages, raised portions formed in the transverse walls and extending into the respective passage, and ridges and troughs formed in the side walls and extending substantially normal to the top and bottom panels of the heat-transfer tube.