Abstract: A heat exchange unit for a heat exchanger which includes a first tube with an outer surface and extended surface members located axially along the outer surface. Each member has a tube engagement surface and are axially Positioned. There is also taught a heat exchange fin block having a heat exchange unit with a second tube interconnected to the first tube by the extended surface members, wherein the extended surface members being tube fins at predetermined axial spacings. A tube finning machine is disclosed which includes a base with clamping means mounted thereon, carrier means movable relative to the base, and drive means for moving the carrier means. The clamping means clamps a portion of the first tube, and the carrier means transports at least one fin to an axially predetermined position adjacent the portion.

Abstract: A heat exchange tube useful as a reactor tube for producing ethylene and highly improved in heat transfer efficiency has fins formed on the inner surface of wall of the tube in one or a plurality of regions or all regions arranged from an inlet end of the tube to an outlet end thereof axially of the tube. The fins are positioned in a direction intersecting the axis of the tube and have a suitable pitch. The fins are formed by a projection helically extending on the tube wall inner surface around the axis or are each in the form of an annular projection circumferentially extending on the inner surface in a direction intersecting the axis at right angles therewith. The pitch of the fins, the angle of intersection of the fins with the axis and the height of the fins are suitably determined in conformity with the inside diameter of the tube.

Abstract: A heat exchanger fin having enhanced corrugations is provided. The corrugations define a generally sinusoidal wave pattern in a transverse direction across the fin. The fin is particularly well-suited for use in a heat exchanger, such as an evaporator or condenser, in a refrigeration system where the spacing between adjacent fins tends to be greater than in an air conditioning system. For example, when the spacing between adjacent fins is in a range from about 2 to 8 fins per inch, the height of the corrugations is greater than the fin spacing. The greater corrugation height bends the air passing between adjacent fins to a greater extent than prior art corrugated fins, thereby causing a greater volume of air to follow the contours of the corrugations and to come into contact with the surfaces of the fins to enhance heat transfer between the air and the fins. Further, the airflow upstream of the fin collars is defined by a larger vortices than in prior art corrugated fins, which further improves heat transfer.

Abstract: A coil assembly for use in a heat exchanger having air flowing in a predetermined direction. The coil assembly comprises a plurality of parallel linear tubes, a plurality of return tubes interconnecting the linear tubes, and a plurality of fins. Each linear tube has a central portion with an elliptical cross-section and two end portions with round female sockets having circular cross-sections. Each return tube has two end portions with circular cross-sections. Each end portion of a return tube fits into a round female socket of a linear tube regardless of the orientation of the major axes of the linear tubes. The major axis of the elliptical cross-section resides at an oblique angle with respect to the direction of air flow. Each fin comprises a planar sheet of a heat-conductive material with a plurality of holes. The central portion of a linear tube extends through each hole. Each fin securely contacts each linear tube extending therethrough such that heat transfer therebetween is enhanced.

Abstract: A heat exchanger having a plurality of tubes for circulating a refrigerant fluid and a plurality of fins in heat exchange contact with the plurality of tubes. Each of the fins includes a plurality of aligned collars defining at least one row of longitudinally spaced apertures, the plurality of tubes extending through the apertures and engaged by the collars. A pair of reinforcing ribs extend longitudinally of the fin, one of the pair on each side of the at least one row of apertures. A plurality of longitudinally spaced flat portions, lying in a common plane, and extend transversely between the ribs, one of the flat portions circumscribing each of the collars. A plurality of central corrugated portions transversely spaced from the ribs, extend longitudinally, one of the corrugated portions lying between each two of the flat portions. At least two sets of longitudinally extending louvers are located transversely between the central corrugated portion and the ribs and longitudinally between the flat portions.

Abstract: A buried armored power transmission line includes a metal jacket housing at least one conductive busbar. The line is equipped with a cooling device operating by transferring heat from the jacket to the surface of the soil, including a metallic structure fixed to the jacket and extending towards the surface of the soil. This structure has a plurality of vertical first plates connected to the jacket having a vertical dimension such that their top edge is at a permissible calculated depth.

Abstract: A heat exchanger includes a plurality of parallel spaced-apart fins and refrigerant-conducting tubes extending perpendicularly therethrough in a zigzagged arrangement. Slits are formed in each fin wherein there is a pair of slits directly in front of each pipe, a pair of slits at an upper front portion of the pipe, a pair of slits at a lower front portion of the pipe, a pair of slits at an upper central portion of the pipe, a pair of slits at a lower central portion of the pipe, a pair of slits at an upper rear portion of the pipe, a pair of slits at a lower rear portion of the pipe, and a pair of slits directly behind the pipe. The two slits of each pair extend from opposite sides, respectively, of the fin without any space formed between the slits, whereby the slits form contiguous air-conducting passages.

Abstract: A fin tube heat exchanger includes a plurality of fin plates disposed in parallel with one another, spaced at regular intervals and adapted to allow air to flow therebetween, and a plurality of refrigerant tubes disposed in at least two rows, inserted into the fin plates in a perpendicular direction and being adapted to allow a fluid medium to pass therein. Each of the fin plates has a plurality of raised strips which extend in a direction perpendicular to a direction of air flow. A plurality of normal raised strips are formed on both sides of the fin plates in at least one row on an air flow outlet side. A plurality of low raised strips or embossings are formed on at least one side of the fin plates in other rows. The height of the low raised strips or embossings in the other rows are lower than the height of the normal raised strips in the at least one row.

Abstract: A heat exchanger including a heat exchanger conduit and fins arranged on the conduit tubes to further heat transfer between the external fluid flowing over the fins and the fluid flowing within the conduit. The fins include a row of apertures through which tubes of the heat exchanger conduit extend. The leading and trailing edges of the fins are contoured to substantially conform to isotherms around the circulating fluid flowing within the tubes. To achieve this edge configuration while also allowing for a dense packing of fins and tubes in a multi-row heat exchanger, the leading and trailing edges are wave shaped such that adjacent fins can interfit together. Suitable wave shapes include a sinusoidal wave as well as a trapezoidal wave. The isothermally contoured leading and trailing edges result in a fin configuration which efficiently utilizes the materials of its construction as well as results in minimal wastage during construction with a minimal impact on heat transfer.

Abstract: A fin for a heat exchanger is disclosed including tubes through which thermal fluid flows; first and second rectangular slits disposed in the fin sequentially from a central line connecting the centers of the tubes, both ends of the slits being in parallel with an air incoming direction; and a third slit having a predetermined plane angle at its outer end adjacent to the tubes in order to reduce vortex flow produced at the rear of the tubes.

Abstract: The fin for a heat exchanger which consists essentially of a matrix of tubes and of fins disposed transversely to the latter, the fin having pass-through elements to receive tubes which are to be joined mechanically, while a first, preferably liquid medium flows through the tubes and the fin is acted on by a second, preferably gaseous medium. Multiple fins are positioned in their fin pitch by integral spacers, wherein the spacers are in the form of noses stamped out of the pass-through elements and distributed over the periphery of the latter.

Abstract: A reactor arrangement and process for indirectly contacting a reactant stream with a heat exchange stream uses multiple passes of the heat exchange stream in a transverse flow arrangement to control temperature conditions over the width and length of channels through which the reactant passes. The heat transfer coefficient may be varied by changing the number and/or the arrangement of the corrugations along the plates or adding a heat adjustment plate to a channel containing the heat exchange fluid. The reactor arrangement and process of this invention may be used to operate a reactor under isothermal or other controlled temperature conditions. The variation in corrugation arrangements within a single heat exchange section is highly useful in maintaining a desired temperature profile in an arrangement having a cross-flow of heat exchange medium relative to reactants. The corrugations arrangement eliminates or minimizes the typical step-wise approach to isothermal conditions.

Abstract: The present invention involves a flat fin heat exchanger configuration with a plurality of louvers and a rib raised above the plane of the fin connecting adjacent tube collars. The raised rib configuration enhances the heat transfer characteristics of the fin, and allows for the use of thinner materials to lower cost without diminishing performance. The exterior fin surface "scoops" and redirects air flow from the leading edge to the trailing edge of the fin. This "scooping" effect directs the air flow over and in between the interrupted surfaces, thus breaking up air boundary layer around the fin. The louvers of the fin are oriented relative to the air flow in such a manner that each louver in effect creates another leading edge contributing to a higher heat transfer coefficient. Also, the location of the raised rib also enhances the heat transfer between the fin and the circulated air.

Abstract: A fin for use in a heat exchanger of the type comprising a plurality of fluid carrying tubes for transporting heat exchange fluid is disclosed. The fin includes a generally planar base 24 having a longitudinal axis generally perpendicular to the direction of air flowing entering the heat exchanger 10 and a transverse axis generally parallel to the direction of air flow. The axes define a main plane disposed at a predetermined angle (.theta.) relative to the direction of air flow entering the heat exchanger. The fin 22 further includes a plurality of apertures 30 for receiving tubes 20 therethrough and a plurality of louvres 32 disposed on the base 24 extending generally parallel to the longitudinal axis of the base. The angle .theta. can be between 140 and 175 degrees to the direction of air flow entering the heat exchanger.

Abstract: A low cost, extended surface, finned-tube of rectangular cross-section is disclosed for use in single-row bundles of the type used in power plant air-cooled steam condensers. The steel U-shaped fins are metallurgically bonded to the steel tubes by hot-dip galvanizing; aluminum fins would be brazed on. The bottom section of the tubes that flow the condensate have a built-in freeze protection feature.

Abstract: A coil assembly for use in a heat exchanger having air flowing in a predetermined direction. The coil assembly comprises a plurality of parallel linear tubes, a plurality of return tubes interconnecting the linear tubes, and a plurality of fins. Each linear tube has a central portion with an elliptical cross-section and two end portions with round female sockets having circular cross-sections. Each return tube has two end portions with circular cross-sections. Each end portion of a return tube fits into a round female socket of a linear tube regardless of the orientation of the major axes of the linear tubes. The major axis of the elliptical cross-section resides at an oblique angle with respect to the direction of air flow. Each fin comprises a planar sheet of a heat-conductive material with a plurality of holes. The central portion of a linear tube extends through each hole. Each fin securely contacts each linear tube extending therethrough such that heat transfer therebetween is enhanced.

Abstract: A fin type radiating system is presented having an exposed rear flange for ease in installing, while improving efficiency. The resulting system is environmentally sound and durable.

Abstract: Louver segments of a heat transfer fin each have a longitudinal central portion disposed at the center of the louver segment in a direction crossing the flow of a fluid and longitudinal end portions each disposed on either side of the longitudinal central portion and sectioned into parts. Each louver segment has a configuration such that an area of the longitudinal central portion projected in the direction of the flow of the fluid is larger than an area of each of the longitudinal end portions projected in the direction of the flow of the fluid, with respect to the same width of the passage of the fluid.

Abstract: Cooling device of a magnetron for a microwave oven, which includes a plurality of radiation fins disposed between an outer periphery of an anode cylinder and an inner surface of a yoke serving as a frame for radiating heat of a high temperature produced during osicillating operation of the magnetron for generating an electromagnetic wave. The temperature of the fins disposed centrally in substantially the same as the temperature of the fins disposed at both ends of the anode cylinder. This is accomplished by, the fins disposed centrally on the outer peripherey being arranged at a diffeent distance from the distance between the fins disposed on both ends of the anode cylinder or by the fins disposed centrally being made of different materials from the materials of the end.

Abstract: A device for indirectly heating fluids, particularly for high temperature processes, includes a heating space in which at least one tube coil is arranged. The tube coil is constructed in a planar manner and the fluid to be heated can be conducted through the tube coil. Heat radiators act from the outside on the tube coil. The heat radiators have a heat radiation surface shaped corresponding to the planar extension of the tube coil. The heat radiators are arranged on opposite sides of the tube coil. Longitudinal ribs are provided on two opposite sides of the tube of the tube coil with respect to the tube cross section.

Abstract: A finned heat exchanger for increased heat transfer from liquid to air, includes of a plurality of stacked thin plates of conductive metal sheeting which are provided with stamped and drawn, slightly conical collars of elliptical, oval or other oblong cross section. The plates are stacked and assembled with the collars of each sheet forcefully pushed into the collars of the adjoining plate, thus effecting tightly closed ducts for the passage of the liquid. The thus-created ducts are arranged in rows and columns, wherein the long axes of the oblong cross section are inclined towards the center line of each column at an angle of 12.degree.-16.degree. to the left and to the right in alternate columns, and wherein the ducts in the rows are staggered in the direction of air flow, every second duct being disposed in forward direction by about half the length of the long axis of its cross section.

Abstract: A heat exchanger apparatus for more effective use of a heat or hot water pipe as a radiant heat source. A pair of tubular members having a semi-circular lateral cross-section and outwardly extending fins attach to the outside surface of a pipe. The tubular members are held adjacent to the pipe by a spring clamp.

Abstract: A heat exchanger tube having fin elements angled in an acute manner from a lateral axis of the flow tube to promote the deflection of debris. The heat exchanger may have a deflector element positioned between the fin elements to prevent the collection of debris between the fin elements.

Abstract: A device including an integrally formed membrane oxygenator and heat exchange device positioned in a single housing. The device includes a thermally conductive body formed with a plurality of blood pathways on its surface, and a gas permeable membrane, or membranes positioned in the housing in substantial contact with the heat exchange body to cover or lie within a portion of each of the pathways. The membrane defines a gas pathway separate from the blood pathway through which a gas is directed. The blood is directed through the individual blood pathways. The device also includes various ports and passageways for delivering the blood to the individual channels, and for collecting and removing the blood from the device.

Abstract: A plate fin heat exchanger is made such that the distance between the trailing edge of its plate fins and the nearest row of tube openings is substantially greater than the distance between the leading edge and its tube openings, thereby reducing the occurrence of condensate carry-over into the airflow stream.

Abstract: The fin-tube heat exchanger includes a group of fins arranged parallel to one another at predetermined intervals; cylindrical fin collars formed on each fin at a predetermined column pitch and a predetermined row pitch; and heat transfer tubes extending through the respective fin collars and secured thereto in intimate contact therewith. Seat portions are formed on each fin around the fin collars. A curved protuberance of a generally angular cross-section is formed on the fin adjacent to an outer periphery of each of the seat portions, which has a ridge line of an arcuate or circular shape arranged in concentric relation to the associated fin collar. A plurality of straight protuberances of a generally angular cross-section are formed on each fin adjacent to outer peripheries of the respective seat portions between any two adjacent rows of the fin collars. With this structure, heat transfer performance is improved by a turbulence promoting effect of the straight protuberances.

Abstract: A plate fin heat exchanger has a group of fins arranged at predetermined intervals so that an air current flows between the respective fins and a group of tubes respectively inserted into and joined to the cylindrical fin collars which are formed in the fin group with a predetermined longitudinal pitch and lateral pitch. Elliptical seats each having a longitudinally extending short axis are respectively provided around the fin collars on the surface of each of the fins, and seat-side ridge portions are respectively formed along the outer peripheries of the seats. A plurality of fin-side ridge portions, each having a longitudinally linearly extending ridge and substantially the same height as that of each of the seat-side ridge portions, are formed in each line of the fin collars outside the seat-side ridge portions on each of the fins. The turbulence promoting effect of the fin-side ridge portions, each having a longitudinally linearly extending ridge, improves the heat transfer efficiency.

Abstract: A stack comprises plates (1,2,3,4) having a zig-zag profile and defining diverging-converging passages in the flow direction (L) of the first heat-exchange medium. Each plate (1,2,3,4) has in the direction (M) perpendicular to the flow direction (M) of the first medium several rows (10) of equally spaced openings (11) accommodating tubes (11a) for a flow of the second heat-exchange medium. Each plate (1,2,3,4) has an odd number of portions (12,13) whose zig-zag profile is offset with respect to the zig-zag profile of the adjoining portion by one half of the pitch (t) of the zig-zag pattern of the profile. The rotary die set for producing the plates of this stack comprises two die rolls (19,20). The length of the evolution of the shaping surface (21,22) of each roll (19,20) is divided into an even number of portions of the same length. The zig-zag profile of each portion is offset with respect to the zig-zag profiles of the adjoining portions through one half of the pitch of the zig-zag pattern of the profile.

Abstract: A fin-tube type heat exchanger includes a large number of plate fins arranged in parallel to each other at predetermined intervals for allowing an air stream to flow between them, and heat exchanging tubes having an outer diameter Do and extending through the plate fins in a direction at right angles thereto. The heat exchanging tubes are set in rows spaced apart by a pitch L.sub.1 in a direction parallel to an air stream as represented by1.2 Do .ltoreq.L.sub.1 .ltoreq.1.8 Do,and are spaced in each of the rows by a pitch L.sub.2 in a direction perpendicular to the air stream as represented by2.6 Do .ltoreq.L.sub.2 .ltoreq.3.3 Do.Each of the plate fins is formed, between the heat exchanging tubes, with a plurality of cut and raised portions open to the air stream and protruding alternately is opposite directions from a base plate of the plate fin.

Abstract: A unit to enhance heat transferring through a tube in a condenser-type heat exchanger comprises a series of elements. The elements engage a surface of the tube in contact with a high temperature condensable medium flowing through the exchanger. The elements are spaced apart, positioned parallel and have ring-like configurations. The elements are positioned on an angle so that when the unit is secured to a vertical tube, each element has a low point. These low points align and connect with a vertical riser. In use the tube is one of a set forming a tube bundle fitted into a vessel of the heat exchanger. As heat transfers from the high temperature medium, for example steam flowing through the vessel to a lower temperature medium, for example cooling water flowing through the tubes, the steam condenses on the tube. The condensed steam builds into a thickening film that then flows down the tube. This downward condensate flow is diverted by the elements of the unit and runs to the low point of each element.

Abstract: A device including an integrally formed membrane oxygenator and heat exchange device positioned in a single housing. The device includes a thermally conductive body formed with a plurality of blood pathways on its surface, and a gas permeable membrane, or membranes positioned in the housing in substantial contact with the heat exchange body to cover or lie within a portion of each of the pathways. The membrane defines a gas pathway separate from the blood pathway through which a gas is directed. The blood is directed through the individual blood pathways. The device also includes various ports and passageways for delivering the blood to the individual channels, and for collecting and removing the blood from the device.

Abstract: In order to be able to use materials of higher strength without the danger of cracks arising during deformation, it is proposed, with reference to a heat exchanger having lamella fins, which are held at a distance from and parallel to each other by shaped collars on the lamella fins and which are penetrated by pipes running parallel to each other in passages through the collars, the internal diameter of the passage in each case matching the external diameter of the pipe and at least partially contacting the external periphery of the pipe, while at the same time exactly preserving the distances between the lamella fins, that tongues are distributed on the periphery of the punched rim of the passage, the free ends of the tongues are bent at an angle to the pipe projecting through the passage, and that these bent tongues provide space locating surfaces for the adjacent parallel lamella fin. Also disclosed is a heat exchanger assembly.

Abstract: A fin-and-tube heat exchanger comprises a fin plate, a heat exchanger tube having portions extending through the fin plate, a plurality of fin collars formed in the plate, wherein louvers are provided so as to surround the tube portions except areas nearest to the collars, the louvers are in parallel with one another and project from alternately both surfaces of the plate, the louver which is located at the trailing edge side and at a position near to a central line of the tube bank is longitudinally extended so as to be along the collars and has opposite rising ends extending from the plate slanted toward the corresponding tube portions at an angle of 35 deg or below to the flow direction of the fluid, and the louver which is located at a position nearer to the trailing edge is also longitudinally extended and has opposite rising ends extending from the plate slanted toward the corresponding tube portions at an angle of 35 deg or above to the flow direction of the fluid so that the angle between the rising e

Abstract: A heat conducting fin for a heat exchanger is provided with an array of deep drawn collars defining passages with flattened, oval cross-sections for receiving heat exchanging pipes of a corresponding cross-section. In order to prevent the formation of cracks in the collars particularly when a large ratio of the maximum diameter to the minimum diameter of the oval collar involves very small radii of curvatures, the height of the collar in the region of its small radius of curvature is less than in the region of its large radius of curvature. The invention also relates to a heat exchanger including a stack of such fins and a series of heat exchanging pipes passing through the passages in the collars and being attached to the inner walls of the collars by expanding corresponding pipe portions.

Abstract: A finned tube heat exchanger having an improved flat louver fin configuration for increased heat transfer efficiency and low air pressure drop. The fins comprise generally planar sheet metal plates having a pattern of spaced apertures for receiving a group of heat exchanger tubes perpendicularly to the fin plate. Groups of louvers are formed as elongate strips extending generally in an area between adjacent tubes. The strips are selectively offset, i.e. raised or lowered from the nominal plane of the fin, so as to establish a louver pattern having flat louvers in a number of different planes each parallel to the direction of flow of air across the fin. Stiffness is provided for the fin plate by providing a slope and offset of the leading and trailing edges of the fin plate such that they are displaced in a direction parallel to the axes of the tube.

Abstract: Essentially triangular turbulators 3 extending at an angle .alpha. to the tube longitudinal plane RLE running through the tube axis RA as well as parallel to the fluid flow direction FSR are arranged on the flat lateral ribs 2 of a heat exchanger tube 1. The turbulators 3 are stamped out of the rib plane and are then bent off at an angle of approximately 90.degree.. They have flash or parting lines 4 rising in the fluid flow direction FSR as well as in the direction of the heat exchanger tube 1. This allows generation of longitudinal vortices 5 downstream of the turbulators 3 which roll over the boundary layers in this location and improve the heat transfer.

Abstract: In a finned tube product of the type having a flat thin fin wound helically on a heat exchange tube, wherein the fin is made from a material having a relatively higher coefficient of thermal expansion than the material of the tube, the improvement which comprises winding a wire helically on the surface of the tube in side by side relation with the fin and simultaneously with the winding of the fin on the surface of the tube such that each winding of wire is snuggly received between adjacent windings of fin, the wire being made of a material having essentially the same or smaller coefficient of thermal expansion as compared to the material of the tube and the longitudinal dimension of thickness of wire representing the desired spacing between adjacent windings of fin on the tube.

Abstract: A compressible heat-dissipating fin, a compressed heat-dissipating fin assembly, and a method for making a fin assembly for cooling an electromechanical device such as a transverse-flow forced air-cooled ion gas laser are disclosed. Each fin preferably has a slit running through its center except for a small hinge. The slit provides the fin with compressibility and increased contact pressure when the fin is fitted directly to and compressed against the tube, preferably by clamping, during the brazing cycle.

Abstract: A rib or fin for the joint ribbing of a plurality of heat exchanger tubes in a ribbed-tube heat exchanger for motor vehicles in which the ambient air flows as a first heat exchange fluid along the surface of the rib or fin and a second heat exchange fluid is conducted in the heat exchanger tubes. The rib is corrugated in the direction of flow of the first fluid. The rib is provided with shaped-on connecting sleeves which serve as a connection to the heat exchanger tubes. At least one wave crest of the corrugation extends between two connecting sleeves that are adjacent one another transversely to the flow direction of the first fluid, and local air guidance profiles are shaped in the corrugated surface of the rib in the spaces between the connecting sleeves. The air guidance profiles are constituted by at least predominantly closed bulges which have a lower height than the distance between the ribs when assembled in the heat exchanger and the bulges are each disposed on a slope of the corrugation.

Abstract: A sine-wave like plate fin for a finned tube heat exchanger coil is provided having an improved enhanced heat transfer area between adjacent pairs of holes in the plate fin. The enhanced heat transfer area includes a plurality of raised lance elements disposed thereon generally at the peaks and troughs of the sine-wave wherein the raised elements at the peaks are concave and the raise elements at the troughs are convex.

Abstract: A fin tube heat exchanger is internally provided with a plurality of plate-shaped and regularly spaced fin members, a plurality of heat exchanger tubes inserted into through-holes defined in each fin member and a plurality of raised pieces formed in each fin member in a plurality of rows. The raised pieces in the same row are raised from a fin base in a direction opposite to the direction in which the raised pieces in adjacent rows are raised. The number of the raised pieces in each row is gradually increased as their row is located farther from a common center line of the through-holes. The raised pieces are integrally formed with and raised from the fin base between adjacent heat exchanger tubes so that two slits defined between the fin base and each raised piece may be open against the air flow.

Abstract: A heat exchanger having a plurality of parallel pipes arranged in lines and strips of fin plates fixed to the pipes perpendicularly to the lengths thereof. Turbulence-forming structures are cut out of the fin plates and are bent up at 90.degree. with respect to the planes of the plates, such structures functioning as fin plate spacers and as baffles to direct a fluid medium of inferior heat transfer coefficient which flows in a direction parallel to the planes of the finned plates and perpendicularly to the pipes. The pipes are adapted to conduct a fluid medium of superior heat transfer coefficient. The turbulence-forming structures are disposed in lines on each side of the lines of pipes and in rows which are substantially tangential to the opposite sides of the pipes. The heat exchanger may have a plurality of lines of pipes spaced equally transversely from each other and transvetsely of the direction of flow of the fluid medium of inferior heat transfer coefficient.

Abstract: A multi-pipe once-through boiler having at least one row of a plurality of circumferentially arranged pipes on which a plurality of fins are arranged in such a manner that the fins are in contact with the flow of the combustion gas in a substantially parallel maner. Elements are provided for increasing the heat transfer effect, such as slits in the fins, or an inclined arrangement of the fins, or pipes without fins at the region near to the inlet of the combustion gas passageway, are provided. Furthermore, a heat insulating member for decreasing operational noise as well as a cleaner device for blow-cleaning the combustion gas passageway are provided.

Abstract: A sine-wave like plate fin for a finned tube heat exchanger coil is provided having an improved enhanced heat transfer area between adjacent pairs of holes in the plate fin. The enhanced heat transfer area includes a plurality of rows of triangular ramp wings which generate counter rotating vortices to promote restarting or thinning of the hydrodynamic boundary layer.

Abstract: The heat exchanger is formed of parallel rows of tubes and transverse ribs. The ribs have flat uncorrugated parts extending in zones about and along the rows of tubes as well as corrugated parts extending between the rows of tubes. The flat parts may be separated from the corrugated parts by stepped parts or fillers may be provided in the gaps between the uncorrugated parts. The gaps are to conduct a flow of medium in heat exchange relation to a flow of medium through the tubes. The crests and troughs of each corrugated part extend from the same plane adjacent a flat part and terminate in a similar plane at an adjacent flat part. Streamline-shaped inflow and outflow members aligned with the stepped part of the fin direct the flow of air.

Abstract: A heat exchanger comprises a plurality of regularly corrugated fins placed one over another in layers at regular pitches in a back-to-back arrangement so as to form alternate wide and narrow fluid passage between the adjacent corrugated fins, and each having a plurality of small through holes, a plurality of collars formed in a staggered arrangement, and an annular area not having any small through hole and formed so as to surround the root of each collar; and pipes for passing a secondary fluid therethrough, each inserted through the collars of the layers of the corrugated fins. The height of the collar from the lower surface of the annular area corresponds to the pitch between the adjacent corrugated fins, and thereby the corrugated fins can be assembled at regular pitches simply by placing one over another. The pipes are expanded after being inserted through the collars so that the pipes are firmly and closely joined to the collars for satisfactory heat transmission between the fins and the pipes.

Abstract: A tubular article with circumferential projections having radial or chordal corrugations. The chords have tooth-like formations or are parallel and directed vertically in underground installation. In the last case, the sides of the tube can be devoid of the corrugations, or have them radially or tooth-like. Furthermore, the projections can be skewed and alternating in the opposite directions. Also, the projections can have offset planes. Finally, in case of two corrugations, they are diametrically opposed in a single chordal direction and are represented by rings bent parallel to the applicable load which is adverse with thus prestressed projections.

Abstract: A plurality of rows of circular openings for supporting water tube sections and turbulence fin arrays comprising plural vertically arrayed fin slots for guiding combustion gas to flow upwards at an angle therethrough are provided on each of a plurality of fin plates which are arrayed in parallel and disposed at the upper end of a water heater. The circular openings and the turbulence fin arrays of each row are alternately positioned. Therefore, each circular opening of a lower row is located below either of the turbulence fin arrays of a next higher row and each turbulence fin array of a lower row is located below either of said circular openings of a next higher row.

Abstract: A gas-fired boiler plant comprises a burner bed (10) extending over a flat surface and heat exchanger pipes (61, 62) arranged above the burner bed (10), parallel to the said surface. The heat exchanger tubes (61, 62) comprise pipes (63, 64) equipped with a plurality of flat ribs (65, 65a . . . , 66, 66a . . . ) which extend substantially radially from the said pipes and which are provided in spaced arrangement over the length of the said heat exchanger pipes (61, 62). The ribs are provided with bent-off portions (70, 71, 72, 73, 74, 75). The hot flue gases (82) rising from the burner bed (10) flow through the gaps (84, 84a) formed between the said ribs (65, 65a . . . , 66, 66a . . . ) and pipes (63, 65).

Abstract: A fin-and-tube heat exchanger designed for one-way airflow, in which louvers, formed from the fin stock, progressively increase in length from the fin leading edge to its trailing edge. Their end walls channel air into stagnant air spaces behind the tubes. The tube collars may be offset somewhat toward the fin trailing edge, further reducing the stagnant air zones. In those bent heat exchangers in which air flows in from outside the curve, offsetting the collars also lessens the angular convergence of fin trailing edges inside the curve and presents less resistance to airflow.