Abstract: The present invention provides a novel fins-on-tubes type evaporator/heat exchanger system that is optimized for energy-saving inductive heating thereof, for example by way of application of Pulse Electro-Thermal Deicing/Defrosting (PETD) or equivalent technique thereto, by configuring it to increasing its resistance to a value at which the system's reactance at its working frequency is comparable to, or less than, its electrical resistance. Advantageously, the inventive system may be advantageously configured to comprise the same form factor and interface as a conventional fins-on-tubes type evaporator/heat exchanger component, such that the inventive evaporator/heat exchanger system may be readily utilized for replacement thereof.

Abstract: A liquid supercooling system may include a suction pipe that has a spiral groove around the outer circumference thereof and connects an evaporator with a compressor, a liquid pipe that connects a condenser with an expansion pipe, a heat exchange pipe in which the suction pipe is inserted and of which one end is connected with the liquid pipe such that heat can be exchanged between the suction pipe and the liquid pipe, and a connection block, of which one side is connected to the liquid pipe and of which the other side is connected to the suction pipe and the heat exchange pipe.

Abstract: The present invention concerns a novel thermal sheet, which is divided into at least two passages by means of rolling or welding seams, and thermal sheet modules constructed thereof, wherein the passages are connected through common feed and discharge lines for a cooling or heating agent supply. Such thermal sheets are referred to as multi-passage thermal sheets. The present invention concerns further a heat exchanger having an outer cover, at least two heat transfer modules, at least one of which represents a multi-passage thermal sheet module according to the invention, and feed and discharge lines for a cooling or heating agent supply which are connected with the heat transfer modules, wherein the feed and discharge lines within the outer cover of the heat exchanger are brought together.

Abstract: To obtain a heat transfer tube for a heat exchanger or the like which can obtain predetermined heat transfer performance without increasing in-tube pressure loss. High ridges 22A having 10 to 20 rows with a predetermined height and low ridges 22B with a height lower than the high ridges 22A having 2 to 6 rows between the high ridges 22A and the high ridges 22A are provided on an inner face helically with respect to a tube axial direction.

Abstract: A heat exchanger of an upward combustion condensing boiler maximizes latent-heat recovery efficiency by causing the flow direction of exhaust gas to coincide with the flow direction of condensed water in a latent heat exchange unit. The heat exchanger includes a sensible heat exchange unit that absorbs sensible heat generated from an upward combustion burner; a latent heat exchange unit that absorbs latent heat of vapor included in exhaust gas which has been heat-exchanged in the sensible heat exchange unit; and a condensed-water tray that discharges condensed water generated from the latent heat exchange unit.

Abstract: The present invention relates to a flat tube for heat exchangers, particularly for charge air coolers, having a turbulence insert that lies on the inside, as well as to a heat exchanger, particularly a charge air cooler, having such flat tubes, and to a method for production of such a flat tube.

Abstract: A heat radiating device for radiating heat of a circuit, includes a heat pipe which has a first straight portion and a second straight portion parallel with the first straight portion, and a curved portion connected to the first and second straight portions, a first base which is in contact with the circuit and is joined at a first surface thereof opposite to a surface thereof facing the circuit, to the first straight portion; a plurality of first fins which are provided on the first surface, have flat surfaces perpendicular to the first straight portion, and cross the second straight portion; a second base which has a second surface perpendicular to the first base and the first straight portion and is joined to the first heat pipe; and a plurality of second fins which are provided on the second surface and extend to a direction perpendicular to the second surface.

Abstract: The air exchanger comprises at least one tubular circuit for evaporating a refrigerant and thermally conducting fins (40) fastened to the tubular evaporation circuit and at least one tubular circuit (35) for condensing a refrigerant, which is connected via thermally conducting fins (40) to the evaporation circuit.

Abstract: A liquid-cooled-type cooling device includes a casing having a cooling-liquid flow channel. Fins are provided on an inner surface of a top wall of the casing. Each fin has a wavy shape on a horizontal plane perpendicular to a fin height direction. In a left fin of two adjacent fins, lines of intersection between the horizontal plane and right side surfaces of two slant portions connecting two adjacent wave crest portions and a wave trough portion therebetween intersect each other at a first point located on a first straight line. In a right fin, lines of intersection between the horizontal plane and left side surfaces of two slant portions connecting two adjacent wave trough portions and a wave crest portion therebetween intersect each other at a second point located on a second straight line. The first straight line is located on the right fin side of the second straight line.

Abstract: A heat exchanger provided with a plurality of plate-like fins 2 arranged in parallel with a predetermined interval and a plurality of flat-shaped heat transfer pipes 3 inserted in a direction orthogonal to said plate-like fins 2 and through which a refrigerant flows, in which said heat transfer pipe 3 has an outside shape with a flat outer face arranged along an air flow direction and a section substantially in an oval shape and first and second refrigerant flow passages 31a, 31b made of two symmetric and substantially D-shaped through holes having a bulkhead 32 between the two passages inside, which is bonded to said plate-like fin 2 by expanding diameters of said first and second refrigerant flow passages 31a, 31b by a pipe-expanding burette ball.

Abstract: A heat exchanger structure includes a pipe and a flow-guiding element. The pipe internally defines a chamber, in which the flow-guiding element is disposed. The flow-guiding element includes a helical main body and a plurality of turbulence promoters radially outward extended from two opposite lateral sides of the helical main body. The turbulence promoters are independently arranged on the helical main body with free ends of the turbulence promoters contacting with an inner wall surface of the chamber, so that a fin cooling effect is produced. The turbulence promoters and the helical main body together define at least one flow-guiding section. With the helically distributed turbulence promoters of the flow-guiding element, the heat transfer ability and the thermal performance factor of both laminar and turbulent flows in the pipe can be increased to provide excellent heat transfer effect.

Abstract: In an evaporator that constitutes part of a vehicular air conditioning apparatus, first fins having louvers therein are arranged between first and second tubes. Together therewith, a second fin, which does not have any louvers therein, is provided at a boundary portion between a first cooling section, which faces toward a first front passage through which air from a first blower unit flows, and a second cooling section, which faces toward a first rear passage through which air from a second blower unit flows. In addition, air is supplied to the interior of a casing from the first blower unit and is cooled by the first cooling section, which is partitioned by the second fin, whereas air supplied from the second blower unit passes through the second cooling section, which is partitioned from the first cooling section by the second fin.

Abstract: A heat exchanger having a plurality of heat exchanging aluminum fins with hydrophilic condensing surfaces which are stacked and clamped between two cold plates. The cold plates are aligned radially along a plane extending through the axis of a cylindrical duct and hold the stacked and clamped portions of the heat exchanging fins along the axis of the cylindrical duct. The fins extend outwardly from the clamped portions along approximately radial planes. The spacing between fins is symmetric about the cold plates, and are somewhat more closely spaced as the angle they make with the cold plates approaches 90°. Passageways extend through the fins between vertex spaces which provide capillary storage and communicate with passageways formed in the stacked and clamped portions of the fins, which communicate with water drains connected to a pump externally to the duct. Water with no entrained air is drawn from the capillary spaces.

Abstract: A method of manufacturing serpentine fins for assembly between tubes in a heat exchanger core. The method includes providing a flat metal strip and forming in the strip, multiple rows of split louvers. Each row of split louvers has louvers formed in pairs of adjacent, spaced louver banks extending across the width of the strip. Each row includes ribs formed in the strip parallel to the louver openings and extending across the pair of louver banks. The metal strip has unformed portions extending across the strip width between rows of split louvers for forming folds across the width of the strip. After forming the rows of split louvers, pressure is applied to the strip to cause the flat strip to buckle along the unformed portions forming folds in the strip resulting in the serpentine fin. Preferably, the strip has ribs formed both in the center portion and along the edges.

Abstract: A heating and cooling system for a vehicle seat, may include a housing having an air supply port through which air communicates with the vehicle seat and an air exhaust hole through which air communicates with the outside of the housing, a thermoelectric element located in the housing between the air supply port and the air exhaust hole to selectively heat or cool air, which is directed toward the air supply port or the air exhaust hole, and a first blower fan provided in the air supply port to communicate air between the vehicle seat and the thermoelectric element.

Abstract: A method and apparatus for producing a finned tube comprises the step of securing a tube to a tube clamping device. The method also comprises the step of arranging a plurality of cutters within the cutter head, wherein the cutters rotate with the cutter head. The method also comprises a step of moving the cutter heads into position around the tube and rotating the cutters around an outside surface of the tube in order to cut fins, via the removal of material, into the outside surface of the tube. The removal of the material also will allow for a very thin inner wall to be arranged underneath the fins being cut therein. This methodology will allow for a very light weight, thermally efficient finned tube to be used to produce a heat exchanger for use in turbine engines or the like.

Abstract: A fin has a substantially flat base plane with a first side facing a first direction and a second side facing a second direction. The fin also has a first louver with a leading edge closer to the base plane and a trailing edge offset from the base plane in the first direction, a second louver located at least partially downstream of the first louver, with a leading edge offset from the base plane in the second direction and a trailing edge offset from the base plane in the first direction, and a third louver located at least partially downstream of the second louver, the third louver having a leading edge offset from the base plane in the second direction and a trailing edge closer to the base plane than the third louver leading edge.

Abstract: A baffle system is provided including a first end plate having at least one opening formed therein, and a second end plate having at least one opening formed therein. At least one baffle element extends between the first and second end plates. The at least one baffle element defines a chamber. The at least one first end plate opening and the at least one second end plate opening are blocked so as to prevent fluid flow from the chamber to an exterior of the chamber system through the at least one first end plate opening and through the at least one second end plate opening. In addition, the blockage of the end plate openings is such that fluid flow is enabled into the chamber from the exterior of the chamber through the at least one first end plate opening and through the at least one second end plate opening.

Abstract: In one aspect, a heat transfer unit is provided for increasing the temperature of process fluids, such as gas-phase fluids, having a Reynolds Number (RE) of at least about 275,000 with a low overall pressure drop and without exceeding the wall temperature limits of the material used to construct the heater. The heater generally includes a heater conduit having the gas-phase fluid flowing therethrough and a heat source, such as a radiant heat source, providing an inconsistent or variable heat flux along a length of the heater conduit where the heat source has a peak heat flux greater than an average heat flux.

Abstract: A heat exchanging system (10) comprises a heat exchanger (1) including a tube (2) through which a first fluid flows and a plurality of fins (3) made from thin plates attached to the tube (2) and arranged parallel to each other in the direction along which the tube (2) extends, and a fan (4) for introducing a second fluid between the fins (3). The fin (3) includes concave parts (7) and convex parts (8) continuously and cyclically formed in a zigzag line. The concave parts (7) and the convex parts (8) are so arranged as to extend in the direction crossing the flow direction of the second fluid flowing between the fins (3), and the flow of the second fluid flowing between the fins (3) is made to be cyclically variable.

Abstract: A refrigeration system is provided, such as for use with chillers. The system uses a tube-side condenser, such as a microchannel condenser, along with a shell-side evaporator such as a falling film evaporator. A flash tank economizer is disposed between the condenser and the evaporator, and an inlet valve to the flash tank is controlled based upon subcooling of condensate from the condenser. The vapor exiting the flash tank may be fed via an economizer line to a system compressor. Liquid phase refrigerant combined with some gas phase refrigerant exits the flash tank and is directed through an orifice before entering the evaporator.

Abstract: A heat exchanger includes a plurality of flat tubes in which a fluid flows, and a plurality of fins each of which is connected to flat surfaces of adjacent tubes to increase a heat exchange area on a side of air flowing outside of the tube. The fin includes a plate portion having a plate surface, and fin protrusions protruding from the plate surface of the plate portion. The fin protrusions are provided to be spaced from the flat surface of the tube by a predetermined distance. A flow resistance portion is provided to protrude from the flat surface of the tube toward outside by a protrusion dimension that is equal to or larger than the predetermined distance.

Abstract: When forming fins and heat transfer tubes by aluminum material, a pressure loss in the tube does not increase and a heat exchanger can be provided having heat transfer performance equal to or higher than a copper tube. The heat exchanger includes fins made of an aluminum material having a low deformation resistance and heat transfer tubes made of an aluminum material having a higher deformation resistance than the aluminum material forming the fins, and on whose internal surface the groove is provided to penetrate the fin to be fixed. It is also arranged that the tube axial direction (a) of the inner surface of the heat transfer tube and the direction (b) of the groove provided on the internal surface of the heat transfer tube are substantially parallel. In this case, the groove direction (b) forms an angle of 0 degrees to 2 degrees with respect to the tube axial direction (a) of the inner surface of the heat transfer tube. The depth of the groove of the heat transfer tube after tube expansion is 0.2 mm to 0.

Abstract: An extruded tube for a heat exchanger is provided that includes two at least approximately parallel outer side walls that extend in a longitudinal direction and a transverse direction of the extruded tube and that are connected by two outer narrow sides in a vertical direction of the extruded tube, wherein at least one continuous web extends between the side walls in the longitudinal direction and in the vertical direction and separates at least two ducts of the extruded tube, and wherein at least one of the outer side walls has embossings that serve to form both bulged portions that project into the ducts of the side walls and also bulged portions that extend substantially in the transverse direction of the web, wherein the bulged portions of the at least one web have a controlled orientation with respect to the transverse direction.

Abstract: Indirect heat exchange device comprising heat exchanger tubes arranged in at least 2 layers each of which layers comprises at least 2 heat exchanger tubes wherein the heat exchanger tubes are eccentrically finned (53) heat exchanger tubes having a ratio of surface area of the fins to surface area of the tube of at least 5, and in which device the heat exchanger tubes have similar eccentricity; and method of exchanging heat with the help of such device.

Abstract: An air handling unit has an enclosure, a heat exchanger disposed within the enclosure, and a heating element substantially co-located with the heat exchanger within the enclosure. An air handling unit has a cabinet with a first air opening and a second air opening. A blower is disposed within the cabinet adjacent to the first air opening and a heat exchanger is disposed within the cabinet adjacent to an air outlet of the blower unit and also adjacent to the second air opening. At least one heating element is located adjacent the heat exchanger. A method of constructing an air handling unit includes forming an air handling enclosure, mounting a blower in the air handling enclosure, mounting a heat exchanger in the air handling enclosure downstream of the blower, and mounting at least one heating element in the air handing enclosure downstream of the blower.

Abstract: A fin having a leading edge, a trailing edge opposing the leading edge, and a plurality of leading holes substantially centered along a leading axis. The fin further having a plurality of secondary holes substantially centered along a secondary axis, the secondary axis being substantially parallel to the leading axis and located between the leading axis and the trailing edge, the plurality of secondary holes being located so that the plurality of leading holes and the plurality of secondary holes form a substantially rectangular matrix. The fin further having a plurality of trailing holes substantially centered along a trailing axis, the trailing axis being substantially parallel to at least one of the leading axis and the secondary axis and located between the secondary axis and the trailing edge, each of the plurality of trailing holes being substantially equidistant from the respective two nearest secondary holes.

Abstract: A hot-water storage type hot-water supply device includes a heat pump unit (1) for heating water, a hot-water storage tank (21) for storing hot water heated by the heat pump unit (1), and a hot-water supplying heat exchanger (22) placed so as to extend roughly entirely in a vertical direction thereof and which receives water from a lower side thereof and discharges hot water from an upper side thereof.

Abstract: A heat dissipation device includes a housing internally divided by a partition plate into an upper and a lower space; at least one heat pipe bank having a condensing section and a vaporizing section located above and below the partition plate, respectively; and a blower fan assembly located in the housing corresponding to the vaporizing section. The housing has a first air inlet and a first air outlet located above the partition plate, and outdoor air entering into the housing via the first air inlet to flow through and exchange heat with the condensing section before exiting the housing via the first air outlet; and a second air inlet and a second air outlet located below the partition plate, and indoor air entering into the housing via the second air inlet to flow through and exchange heat with the vaporizing section before exiting the housing via the second air outlet.

Abstract: A method for making heated plane of a cooler obtain better flatness and roughness includes a grinder with a grinding plate and a fixture. Then, the cooler is arranged onto the fixture. Next, the abrasive is injected into the gap between the grinding plate and the heated plane, making the fixture press and clamp the cooler in a way, such that the heated plane of the cooler contacts the abrasive closely. Finally, the grinding plate is rotated to make at least one grinding process to the heated plane, making the heated plane obtain a surface with better roughness and flatness, further enhancing the contact tightness between the heated plane and a heating element, and therefore promoting the thermally conductive efficiency between the cooler and the heating element.

Abstract: A heat transfer tube (101) for a heat exchanger. The wall (120) of the heat transfer tube comprising at least one axially extending wing-shaped protrusion (104, 105) to provide the tube with additional heat transfer surface area. The wing shaped protrusion is formed by a process comprising at least one of: (i) folding the wall of the tube; and (ii) extrusion.

Abstract: A heat dissipation device for removing heat from heat-generating components includes a fin unit. The fin unit includes a plurality of fins stacked together. Each fin is wave-shaped in profile and comprises a plurality of wave crests and wave troughs alternately arranged with each other. The wave crests of one of the fins respectively engage the wave troughs of a neighboring upper one of the fins. The wave troughs of the one of the fins are separated from and located below the corresponding wave crests of the upper one of the fins.

Abstract: A heat exchanger (1) for a dryer, especially for a domestic dryer, has a plurality of fins (2), wherein a flow channel (3) is established between two fins (2), and wherein air is guided along a flow direction (F) through the flow channel (3) from an inlet edge (4) to an outlet edge (5). To improve the behaviour of the heat exchanger as regards the collection of lint, at least the inlet edges (4) of the fins (2) have an at least partially rounded shape (6, 6?, 6?) seen in a direction perpendicular to the flow direction (F) and parallel to the surfaces (7) of the fins (2).

Abstract: A method for fabricating a heat exchanger assembly (20) includes pressing a pair of headers (30, 38) into refrigerant tubes (76). A notch (50) is cut axially into header ends (32, 40). An inner radial abutment (24) is formed in each of the refrigerant conduits (22, 56), which are then each inserted through an open end cap (26). An outer radial abutment (28) is formed in each of the refrigerant conduits (22, 56) so that the open end caps (26) are retained in position between the radial abutments (24, 28). The radial abutments (24, 28) can comprise a bead, a radially inwardly extending shoulder, an outwardly extending shoulder, or an expansion beneath the open end caps (26). A tool presses each subassembly into the corresponding headers (30, 38) until the tool reaches the corresponding notch bottom (52).

Abstract: An air-conditioning apparatus uses carbon dioxide as a refrigerant, and includes comprises a two-stage-compression-type compression mechanism, a heat source-side heat exchanger, an expansion mechanism, a usage-side heat exchanger, and an intercooler. The intercooler uses air as a heat source. The intercooler is configured and arranged to cool refrigerant flowing through an intermediate refrigerant tube that draws refrigerant discharged from the first-stage compression element into the second-stage compression element. The intercooler is integrated with the heat source-side heat exchanger to form an integrated heat exchanger, with the intercooler disposed in an upper part of the integrated heat exchanger.

Abstract: The present invention discloses a flooded type evaporating heat-exchange copper tube for an electrical refrigeration unit. The evaporating heat-exchange tube comprises a smooth surface portion, a finned portion provided with plurality of fins and a transitional portion connecting the smooth surface portion to the finned portion, with primary evaporating chambers defined between the fins. Fifth fins extending upwardly are provided on a bottom wall of the primary evaporating chamber, which divide the primary evaporating chamber into at least two minor cavities, and an evaporating opening is defined between adjacent fins of the primary evaporating chamber. Due to plurality of minor cavities arranged in the evaporating heat-exchange tube, refrigerant film is easy to form on bottom walls of the minor cavities, and nucleus boiling is easily to be developed. Thereafter, the refrigerant gets boiled and evaporated to form bubbles to escape via evaporating openings.

Abstract: A tube for a heat exchanger includes a tube main body (10) with a long plate shape in an extrusion direction and formed with a plurality of fluid paths (1a) through which a fluid for heat exchange flows internally along the extrusion direction, a plurality of concave parts formed with intervals in a pressing direction in which either an upper surface part (1c) of the tube, that is, a surface of one side in a thickness direction of the tube main body (10) or a lower surface part (1d) of the tube, that is, a surface of a reverse direction to the upper surface part (1c) is pressed in the direction, convex parts (1b) projected in a direction that narrows a cross sectional area of the fluid paths (1a) are formed by the pressed concave parts in the fluid path (1a).

Abstract: A heat exchanger for a gas boiler for producing hot water is provided with a casing extending along a first axis and through which combustion fumes flow; a tube forming a plurality of turns along which water flows arranged inside the casing so as to form gaps between adjacent turns; a disk for guiding said fumes trough the gaps; and teeth integrally made with the tube for spacing adjacent turns apart and forming said gaps.

Abstract: The invention relates to a metallic heat exchanger tube (1) with a tube wall (2) and with integrally formed ribs (3) which run around on the tube outside (21) and which have a rib foot (31), rib flanks (32) and a rib tip (33), the rib foot (31) projecting essentially radially from the tube wall (2), and the rib flanks (32) being provided with additional structural elements which are formed as material projections (4) arranged laterally on the rib flank (32), the material projections (4) having a plurality of boundary faces (41, 42), at least one of the boundary faces (42) of at least one material projection (4) being curved convexly.

Abstract: A heat exchanger is used which has heat transfer tubes acting as flow paths of a refrigerant and metal fins having pores opened inward from the surfaces thereof for adsorbing and desorbing moisture in air within the range of a relative pressure of 0.1 to 0.9 so as to transfer heat of the heat transfer tubes to air, wherein the pores have a diameter of 1 to 20 nm and a depth of 1 to 100 ?m.

Abstract: A heat dissipation device according to the present invention includes an inner tube to which heat from LED modules is to be transferred, first fins protruding from an outer surface of the inner tube in a direction crossing the outer surface, and an outer tube covering the inner tube. Moreover, heat is transferred from the surfaces of the inner tube, outer tube and first fins which form ventilation paths (medium paths) to the air flowing at an increased flow rate by a stack effect.

Abstract: Improvements in tubes, which increase the heat exchange capacity of tubular heat exchangers using the tubes, are described. These improvements involve the use of one or more external surface enhancements, optionally combined with an internal enhancement and/or differing tube geometries. These improvements apply, for example, to internal condensers, including those in which the tube bundles are oriented vertically, in vapor-liquid contacting apparatuses such as distillation columns.

Abstract: In a resin heat exchanger unit, a resin pipe having straight portions and curved portions and a plurality of resin fins are integrally molded and there can be realized high reliability, high heat exchange efficiency, and a simple manufacturing process. The resin heat exchanger unit includes a resin pipe (1), which has straight portions (2) and curved portions (3) provided alternatively and continuously, and a plurality of resin fins (4) connected to the pipe (1), the pipe (1) and the fins (4) being integrally injection-molded.

Abstract: The invention provides a method and apparatus for integrating the heat transfer zones of plate fin and tube and finned tube exchangers and a catalytic mass transfer zone. The invention also provides a method for in situ regeneration of existing coated surface and augmentation of existing coated surface, or catalyst performance.

Abstract: A heat exchanger having an active surface over which a fluid flows to affect an exchange of heat between the active surface and the fluid. In some embodiments, the active surface includes a logarithmic spiral wherein the radius of the logarithmic spiral measured at equiangular radii unfolds at a constant order of growth. Further embodiments exhibit an active surface conforming to the internal or external surface of particular classes or genera of shells.

Abstract: A thermal transfer means comprising, fluidly in series: a fluid supply conduit having a fluid inlet (41) adapted for connection to receive fluid from an outlet of a heat source; a heat exchanger (40) comprising a heat exchanger tube having at least one heat exchanger element disposed thereon; and a fluid delivery conduit (42) having a fluid outlet adapted for connection to deliver fluid to an inlet of a heat source. The fluid supply conduit, heat exchanger tube and fluid delivery conduit are integrally formed from a common tube formation fabricated from a single material. The thermal transfer means is suitable for inclusion into a thermal transfer system, for example on a vehicle, for example to serve as an integral cooling line and/or space heater.

Abstract: A heat transfer tube includes a container, a cavity within the container, a substantially homogeneous nanoparticle powder located within the cavity, and a gas. The cavity is in a partial vacuum state. The nanoparticle powder includes a material in a solid state capable of substantially freely emitted and reabsorbing a gas as a function of temperature, such as a hydrate, hydride, or other material.

Abstract: A heat exchanger is provided. The heat exchanger includes a plurality of aluminum tubes formed of aluminum, each of the aluminum tubes including a plurality of grooves that are formed on an inner circumferential surface of each of the aluminum tubes and that extend along a longitudinal direction of the aluminum tubes; and a plurality of heat transfer fins coupled to the aluminum tubes. The heat exchanger may contribute to the reduction of the manufacturing cost, may provide high heat transfer performance and may prevent a coolant leak.

Abstract: Heat transfer devices and methods of making such devices are disclosed. One such device is a fin having a primary texture and a secondary texture, wherein each texture has an average amplitude. The amplitude is an elevation change from a peak of the texture to an adjacent valley. The average amplitude of the secondary texture is between 1% and 90% of the average amplitude of the primary texture. Such a fin may have holes, some of which may be used to accommodate tubes passing through the fin.

Abstract: A case for a heating, ventilating and cooling system may include a shell and a plurality of fins. The shell may define an interior volume and may include an air inlet, a first air outlet and a second air outlet. The interior volume may define an airflow path between the air inlet and the first and second air outlets. The shell may be in fluid communication with a blower. The plurality of fins may be disposed in the airflow path between the air inlet and the first and second outlets. The plurality of fins may extend into the interior volume and distribute a first predetermined airflow amount to the first air outlet and a second predetermined airflow amount to the second air outlet. A temperature of the first predetermined airflow amount may be substantially equal, or different by a predetermined amount, to a temperature of the second predetermined airflow amount.