Abstract: A fluid-carrying tube for a heat exchanger includes an outer perimeter, an inner perimeter, and a plurality of ridges extending from the inner perimeter inwardly into an interior of the tube. Each ridge includes a ridge height, a base width and a tip width. A ratio of the ridge height to the base width is between about 0.2 and about 4.0, and a ratio of the tip width to the base width is between about 0.015 and about 0.965.

Abstract: A heat exchanger includes a plurality of tubes (12), each tube configured for a flow of fluid therethrough and one or more fins located between adjacent tubes of the plurality of tubes. The one or more fins are spaced by a fin pitch (Fp,18) and are configured to improve thermal energy transfer between the plurality of tubes and ambient air. Each fin includes a fin face extending between the adjacent tubes, a substantially planar fin cap (22) connected to the fin face secured to one or the tubes, and a fin radius (Rc,26) connecting the fin face to the fin cap such that the fin radius is reduced to promote condensate removal from the heat exchanger.

Abstract: A free-draining heat exchanger includes a first heat exchange tube, a second heat exchange tube spaced from and generally parallel to the first heat exchange tube, and a fin contacting the first and second heat exchange tubes. The fin includes a louver and at least one drainage enhancement feature for promoting removal of liquid from external surfaces of the heat exchanger. A free-draining fin structure includes an array of fins disposed between adjacent heat exchange tubes for improving water drainage by reducing liquid surface tension. Each fin in the array includes an opening and a louver for directing airflow through the opening and around the fin and at least one drainage enhancement feature.

Abstract: A heat exchanger assembly including a plurality of pairs of plates disposed in series for fluid flow from a pass through one pair of plates to a pass through the next pair of plates. Each pair of plates includes a central rib to define a U-shaped passage having a fluid entering leg and a fluid exiting leg interconnected by an open bottom interconnecting the legs below the lower end of the engaging central ribs. A plurality of dimples project into the passage to interact with fluid flow through the passage and each of the dimples has a hemispherical shape and a divider rib is disposed in the passage to co-act with the hemispherical dimples to reduce whistling noise.

Abstract: A laminate-type evaporator includes U-channel plates in combination with various configurations of dual cup and single cup plates, to control refrigerant pressure drop and achieve enhanced temperature spreads within the evaporator. The U-channel plates define one or more of the final refrigerant passes in the evaporator, and the dual cup and single cup plates define refrigerant passes upstream therefrom. Fins are disposed between adjacent plate pairs and extend to selected end edges of the U-channel plates to maximize the surface area available for heat exchange in the final refrigerant passes.

Abstract: A heat exchanger for a heating, ventilating and air conditioning system comprises a plurality of heat exchange tubes extending between a pair of spaced header tanks and arranged in groups of tubes with varying number of tubes in each group to cause a refrigerant to flow in multiple passes in the interior of the tubes across another fluid flowing on the exterior of the tubes. The heat exchange tubes comprise a plurality of flow passages having at least one corner formed by a pair of straight or arcuate sides with an included angle of less than or equal to ninety degrees, more preferably less than or equal to thirty degrees, to promote intense pool boiling within the flow passages. In addition to at least one corner region, the flow passage has a passage-specific optimal hydraulic diameter determined by the relationship between the optimal hydraulic diameter of the passage and the optimal hydraulic diameter of a baseline circular passage.

Abstract: An evaporator for an HVAC system is disclosed wherein an upstream to downstream airflow is directed through the evaporator for inducing a transfer of thermal energy between the airflow and a fluid circulating in the evaporator. The evaporator includes at least two cores adjacent one to the other. Each of the cores defines a core inlet and a core outlet and the cores are arranged such that the core inlet of the first core is positioned at an opposite end from the inlet of the second core. Correspondingly, the outlet of the first core is positioned at an opposite end from the outlet of the second core. The evaporator inlet is in fluid communication with the first core inlet and the second core inlet and the outlet is in fluid communication with the first core outlet and the second core outlet.