Abstract: A heat exchanger has first and second manifold portions and an array of substantially-parallel heat-transfer tubes extending between the first and second manifold portions. Each heat-transfer tube has an outer surface and an inner surface defining a conduit. In a cross-sectional view, the outer surface of each heat-transfer tube can form a first shape that is non-circular, and the inner surface of heat-transfer tube can form a second shape different than the first shape. Alternatively or additionally, at least one of the first shape and the second shape lacks reflectional symmetry in the cross-sectional view. Methods for fabricating such heat exchangers are also provided.

Abstract: A solar energy collecting system and method suitable for hot water generation using solar energy. The system includes multiport tubes between inlet and outlet manifolds. The tubes are formed of a metallic material, each tube has oppositely-disposed first and second flat surfaces between lateral edges thereof, longitudinally-opposed first and second ends, and multiple fluid channels between the first and second ends that are in fluidic parallel to each other. The inlet and outlet manifolds are coupled to the first and second ends of the tubes so that chambers within the inlet and outlet manifolds are fluidically connected to the fluid channels of the multiport tubes. During operation of the system, a fluid flowing through the fluid channels of the tubes is heated by direct solar radiation impinging the first flat surfaces of the tubes and optionally by reflected solar radiation impinging the second flat surfaces of the tubes.

Abstract: A tube mill apparatus and process for continuously forming and coating a tube with a braze alloy. The apparatus and process produce a continuously moving welded tube by continuously forming and welding a tubing material, after which the welded tube is passed through a sizing station to establish a desired outer shape and desired outer dimensions for the welded tube. The braze alloy is then deposited on a roughened surface of the welded tube that is clean and free of oils and coolants. The braze alloy is deposited with a wire arc spray gun that heats a wire of a metallic material and causes the heated metallic material to travel in a direction transverse to the direction of tube travel and deposit on the roughened surface of the tube to form an adherent layer of the braze alloy. Finally, any bow in the welded tube is removed as the tube travels away from the spray gun.

Abstract: A solar energy collecting system and method suitable for hot water generation using solar energy. The system includes multiport tubes between inlet and outlet manifolds. The tubes are formed of a metallic material, each tube has oppositely-disposed first and second flat surfaces between lateral edges thereof, longitudinally-opposed first and second ends, and multiple fluid channels between the first and second ends that are in fluidic parallel to each other. The inlet and outlet manifolds are coupled to the first and second ends of the tubes so that chambers within the inlet and outlet manifolds are fluidically connected to the fluid channels of the multiport tubes. During operation of the system, a fluid flowing through the fluid channels of the tubes is heated by direct solar radiation impinging the first flat surfaces of the tubes and optionally by reflected solar radiation impinging the second flat surfaces of the tubes.

Abstract: The invention relates to a method of manufacturing and coating heat transfer parts for a heat exchanger such as tubes in an automobile radiator. The tubes are coated with brazing material by thermal spraying, such as plasma deposition or wire-arc deposition. The coating is then melted by application of heat to braze the tubes to the fins and to the headers to complete the formation of the heat exchanger.

Abstract: A charge air cooler formed of copper or a copper alloy for withstanding high temperatures and high pressures is described. The charge air cooler is made to withstand temperatures over about 300° C. and pressures greater than about 40 bars in one embodiment, and temperatures over about 600° C. and pressures greater than 40 bars in additional embodiments. The heat transfer tubes are connected to manifolds at either end. The manifolds are preferably formed of copper or copper alloy with the tubes mechanically joined thereto. In one embodiment, the tubes are arranged in alternating angles with respect to each other. In a preferred embodiment, the tubes are arranged in offset alternating angles with respect to each other.

Abstract: The invention relates to a method of manufacturing and coating heat transfer parts for a heat exchanger such as tubes in an automobile radiator. The tubes are coated with brazing material by thermal spraying, such as plasma deposition or wire-arc deposition. The coating is then melted by application of heat to braze the tubes to the fins and to the headers to complete the formation of the heat exchanger.

Abstract: The invention relates to a microchannel tube for use in a heat transfer system. The microchannels have openings in the partitions that separate them from each other, thereby creating many short interconnected passages through which a heat transfer medium will flow. This permits the liquid and vapor phases of the medium to mix, thereby increasing the efficiency of the system.

Abstract: The invention relates to a method of manufacturing heat transfer tubes for a heat exchanger such as an automobile radiator. The tubes are preferably formed of copper or a copper alloy. A sheet of the material is folded into a shape that resembles a B and is brazed together with a brazing material that is free from flux. The brazing material is in the form of a foil or paste. The paste typically includes a powder filler, a binder, and a carrier, which may be a liquid or a wax.

Abstract: The invention relates to a method of manufacturing heat transfer tubes for a heat exchanger such as an automobile radiator. The tubes are preferably formed of copper or a copper alloy. A sheet of the material is folded into a shape that resembles a B and is brazed together with a brazing material that is free from flux. The brazing material is in the form of a foil or paste. The paste typically includes a powder filler, a binder, and a carrier, which may be a liquid or a wax.