Patent ID: 8020298

Claim:
A method of fabricating a heat exchanger, the method comprising: obtaining a plurality of coolant-carrying conduit sections, each of the coolant-carrying conduit sections having a non-circular cross-section and comprising a first flat main surface and a second flat main surface; forming a plurality of primary folded fins and securing the plurality of primary folded fins to the plurality of coolant-carrying conduit sections, each of the primary folded fins being formed by bending a solid plate fin surface into a plate fin comprising a plurality of bends defining alternating, substantially U-shaped air-passage channels, and a base surface and a top surface, and each of the primary folded fins having at least one of the base surface and the top surface thereof secured to at least one flat main surface of at least one adjacent coolant-carrying conduit section of the plurality of coolant-carrying conduit sections, and the plurality of primary folded fins each having a leading edge and a trailing edge relative to an anticipated direction of airflow through the plurality of primary folded fins, the leading edge and the trailing edge of each of the primary folded fins being opposite edges of the primary folded fin and wherein the airflow through the plurality of primary folded fins is from the leading edges thereof, through the U-shaped air-passage channels and out from the trailing edges thereof; wherein the forming further includes forming a plurality of sets of secondary fins, each of the sets of secondary fins extending from one of the leading edge or the trailing edge of a respective primary folded fin of the plurality of primary folded fins, the forming the plurality of sets of secondary fins comprising angling each of the secondary fins extending from a respective primary folded fin at other than 0° to facilitate airflow through the heat exchanger, and wherein each of the primary folded fins and respective set of secondary fins is a substantially V-shaped structure in top plan view; and wherein at least one coolant-carrying conduit section of the plurality of coolant-carrying conduit sections has a first primary folded fin of the plurality of primary folded fins secured to the first flat main surface thereof, and a second primary folded fin of the plurality of primary folded fins secured to the second flat main surface thereof.