High performance lanced sine wave fin configuration

#Embodiments of the present disclosure relate to the art of finned tube heat exchanger coils, and more particularly, to plate fins including a lanced sine-wave heat transfer surface for use in heating, ventilation, and air-conditioning and a method for manufacturing thereof.

#Lanced fins have been used previously to provide a surface variation that enhances the transfer of heat energy between the fluids passing through the tubular members and over the plate fin surfaces. Although the existing lanced fin design, in which the lance elements are moved upwardly relative to the plate fin has been in use for years, no optimization of such a configuration has been performed due to the inherent complexities of the geometry of the lanced fin. In most applications, a single fin-die equipment is used to manufacture a family of heat exchangers with a range of fin densities. Although the fin surface design remains same, the spacing between the fin changes by varying the fin collar height. While the fin spacing is a variable parameter within certain limits, the lance-offset is a fixed design parameter for the given fin-die and is a function of the spacing between two adjacent fins.

#According to an embodiment, a heat exchanger includes a plurality of plate fins. At least one plate fin has a plurality of holes arranged in one or more rows and a contoured region formed adjacent one of the plurality of holes having a sinusoidal corrugation. The contoured region includes a plurality of elongate adjustable lance elements. The plurality of elongate adjustable lance elements are lowered relative to a central plane arranged at a midpoint of an amplitude of the sinusoidal corrugation.

#The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:

#FIG. 1 is a perspective view of an exemplary round tube plate fin heat exchanger coil according to an embodiment;

#FIG. 2 is a plan view of a plate fin of the round tube plate fin heat exchanger coil of FIG. 1 according to an embodiment;

#A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

#Referring to FIG. 1, an exemplary plate finned tube heat exchanger coil 20 is illustrated. As shown, the heat exchanger coil 20 includes at least one plate fin 22, such as a plurality of plate fins for example. Each plate fin 22 has one or more holes 24 formed therein for receiving one or more tubes 26 of the heat exchanger coil 20. The plurality of plate fins 22 are maintained together by oppositely positioned tube sheets 28 having holes 30 therethrough in axially alignment with tube holes 24. The plurality of tubes 26 are laced through the holes 24, 30 formed in the plate fins 22 and the tube sheets 28 and have their open ends joined together in fluid communication by u-shaped return bends 32, which are secured to the tubes 26 by soldering, brazing or the like. In an embodiment, there is no interference between the tubes 26 and the tube sheets 28; rather, the tubes 26 are only arranged in contact with the plate fins 22.

#In operation, a first fluid to be cooled or heated flows through the tubes 26 and a second cooling or heating fluid is then passed between fin sheets 22 and over an exterior surface of the tubes 26 in a direction indicated by arrow A. Heat energy is transferred from or to the first fluid through the tubes 26 and the plate fins 22 to or from the other fluid. The fluids may be different types, for example, the fluid flowing through tubes 26 can be a refrigerant and the fluid flowing between plate fins 22 and over the tubes 26 can be air. However, embodiments where the fluids are the same type of fluid are also contemplated herein.