Abstract: A closed channel rotary regenerative air preheater 110 employs differing heat transfer elements 186, 196, arranged in an alternating order to impart turbulence in fluid flowing in closed channels or passageways 164 between the heat transfer elements 186, 196, to maintain heat transfer properties with reduced pressure drop.

Abstract: A method of manufacturing a recuperator segment uses metal tubes deformed into air cells in a waved configuration. The air cells are stacked one to another to form a double skinned recuperator segment providing cold air passages through the respective air cells and hot gas passages through spaces between adjacent air cells.

Abstract: A manufacturing method and structure of a heat exchanger for a bathing shower involves two plates welded together to form a passage for cold water. Hot water from the shower drips onto the upper plate and transfer heat to cold water flowing through the passage between the plates. The upper plate may be spot welded to the lower plate at bottoms of frustoconical indentations in the lower plate, the plates may sandwich an adiabatic layer, and/or the passage between the plates may be formed by pipes situated between the plates.

Abstract: A recuperator disposed in the exhaust duct of a gas turbine engine includes a plurality of recuperator plates arranged in a spaced-apart relationship to define therebetween a plurality of interstices and fluid channels, the plurality of interstices adapted to direct therethrough at least one first stream received at a leading plate edge of the recuperator plates and the plurality of fluid channels adapted to direct therethrough at least one second stream to effect heat exchange between the at least one first stream and the at least one second stream. Each recuperator plate includes, formed at the leading plate edge thereof, a first concavity extending along the leading edge in a direction substantially parallel to a longitudinal axis of the plate. The first concavity extends transversely to a direction of the at least one first stream flowing over each recuperator plate.

Abstract: The effectiveness of heat transfer to and from a thermal energy storage medium, for example a phase change medium, is enhanced by the inclusion of thermally-conductive elements within the thermal energy storage medium. The thermally-conductive elements may be filler shapes placed in a self-supporting stacking arrangement, which may be a random stacking arrangement. The effective thermal conductivity of the matrix that includes the thermal energy storage medium and the thermally-conductive elements is higher than the thermal conductivity of the thermal energy storage medium itself. Other thermally-conductive elements may be used, for example thermally-conductive sheets.

Abstract: A forced oscillation radial seal is described for regenerative air preheaters which contain rotatable radial plates having upper and lower edges. The forced oscillation seal includes a base with a first portion attached to a lateral face of the plates adjacent the upper and lower edges, and a second free portion, with a pivot system having an axis attached to the second free portion, and a rigid sealing sheet with a first free portion, second portion, and central portion, the sealing sheet attached at its central portion to the pivot system. The forced oscillation seal includes a counterweight attached to the sealing sheet so the sealing sheet reassumes a vertical position after forming a seal with a sealing surface, and a plurality of springs in contact with the sealing sheet and base along the axis of the pivot system, which cooperate with the counterweights to force the seal to oscillate.

Abstract: A regenerator (100), for a thermal cycle engine with external combustion, according to the invention comprises a network of metal fibers wherein a majority of the fibers at least partially encircles the axis of the regenerator. The fibers were part of a fiber bundle which is coiled and sintered thereby obtaining the regenerator.

Abstract: An object of the present invention is to provide a readily produced and easily handled heat storage member. The heat storage member 1 has a rectangular plane surface of, for example, 15 (cm)×20 (cm), and has a thickness of, for example, 10 to 15 mm. The heat storage member 1 includes a gelatinous latent heat storage material 12, and a large number of highly heat conductive fillers 14 dispersed in the latent heat storage material 12. The highly heat conductive fillers 14 are mixed in the latent heat storage material 12 with a bias in dispersion density. In the rectangular plane surface of the heat storage member 1, a periodic pattern is formed in combination of cellular (cell-like) regions 10, which are demarcated by, for example, hexagonal contour lines 16 and which are periodically arrayed in the vertical and horizontal directions.

Abstract: Disclosed is a heat transfer assembly for a rotary regenerative preheater. The heat transfer assembly, includes, a plurality of heat transfer elements stacked in spaced relationship to each other in a manner such that each notch from a plurality of notches of one of the heat transfer element rests on respective flat sections from a plurality of flat sections of the adjacent heat transfer elements to configure a plurality of closed channels, each isolated from the other, wherein each of the channels has a configuration in a manner such that each of corrugation sections from a plurality of corrugation sections of one of the heat transfer elements faces respective undulation sections from a plurality of undulation sections of the adjacent heat transfer elements.

Abstract: A method of manufacturing a cryogenic regenerator includes the steps of supplying helium gas to a helium gas sealing tube having a front end portion and a rear end portion that are open; sealing the rear end portion of the helium gas sealing tube; cooling the helium gas sealing tube and filling the helium gas into the cooled helium gas sealing tube from a helium gas supplying unit; and sealing the front end portion of the helium gas sealing tube after the helium gas sealing tube is filled with the helium gas.

Abstract: A refrigerator and a manufacturing method thereof including processes of separately manufacturing partitions dividing a storage space into a plurality of storage chambers from a main body including an inner casing and an outer casing, coupling the partitions to an inner surface of the inner casing, filling a space between the inner casing and the partitions with an insulator, and filling the partitions with the insulator by filling a space between the inner casing and the outer casing with the insulator. Since the insulator uniformly fills the partitions dividing the storage space into the plurality of storage chambers, the partitions may possess improved insulating qualities.

Abstract: An apparatus is disclosed to seal a sector-plate at a diaphragm for an air duct. The apparatus includes a flexible seal including a radial seal body. The radial seal body produces a travel path with a major axis when operatively coupled with the diaphragm. Mounting hardware includes a rail to maintain a defined beam position of the radial seal body relative to the diaphragm.

Abstract: A heat exchange module 12 is formed by stacking pipe groups obtained by fixing a plurality of pipes 1 with use of pipe array holding members 9a to 9d. Flow path forming members 50 are arranged on pipe groups in the uppermost and lowermost layers, and walls 51 and 52 are provided so as to protrude from the outer-side pipe array holding members and the inner-side pipe array holding members. Flow path members 63 are provided between the walls 51 and 52 adjacent to each other so as to allow through holes 53 and 54 to communicate with each other. The heat exchange module 12 is housed in the housing 2, and while rotating the housing 2, a resin material 24 is filled into a space enclosed by the two inner-side pipe array holding members of each pipe group in the housing 2, interstices around the pipes present between an opening 15a of the housing and the outer-side pipe array holding members, and interstices around the pipes present between an opening 15b of the housing and the outer-side pipe array holding members.

Abstract: A work vehicle comprises an internal combustion engine and a catalytic converter coupled to the exhaust of the engine. A reduction agent system provides for injection of a reduction agent, such as urea, upstream of the catalytic converter. Coolant heated by the engine is directed to the reduction agent system to defrost/heat the reduction agent, and is also directed to a vehicle cabin heating system. Flow of coolant may be preferentially directed to the cabin heating system rather than to the reduction agent system, such as following vehicle startup, particularly during cold-weather operation. Flow may be altered to favor the reduction agent system, such as based upon time and/or the temperature of the cabin.

Abstract: A semi-modular rotor module [52] for a modified modular air preheater [10] has a two-pin lug assembly for engaging an air preheater post [16]. The two-pin lug assembly includes an upper two-pin lug [54] and a lower two-pin lug and is configured to occupy a sector sealing plate angle ?. A plurality of diaphragms [56], [58], [60], [62] extend radially from the two-pin lug assembly, including two outer diaphragms [56], [62] positioned to define a sub-sector angle ? that is less than the sealing plate angle ?. Stay plates [42] are between the diaphragms to define basket modules where heat exchange elements [22a] are received. A modular rotor can be modified by removing pairs of adjacent unitary rotor modules [20] and replacing each pair with the semi-modular rotor module [52].

Abstract: The invention concerns a heat exchanger for transmitting heat from a heating medium, in particular from the exhaust gas stream of an internal combustion engine, to a working fluid, which evaporates in the heat exchanger, comprising an alternating stacking order made of guiding layers for the heating medium and guiding layers for the working fluid; wherein the heating medium and the working fluid are injected in the cross counterflow; whereas each guiding layer for the working fluid comprises a channel plate, which has at least one meandering passage opening, whereas cover plates are arranged on both sides of the channel plate, which cover plates seal laterally the passage opening by forming a working fluid channel, except for an inlet and an outlet, wherein the channel plate is materially connected to the cover plates; and whereas the working fluid channel includes a first section, outgoing from the inlet, with a first free cross-section and a second section emerging in the outlet, with a second free cross-se

Abstract: A regenerator (100), for a thermal cycle engine with external combustion, according to the invention comprises a network of metal fibers wherein a majority of the fibers at least partially encircles the axis of the regenerator. The fibers were part of a fiber bundle which is coiled and sintered thereby obtaining the regenerator.

Abstract: A storage cabinet (16) is provided for an ultra-low temperature freezer (10). The cabinet (16) includes a base platform (62a), a plurality of side structural insulated panels (45, 50, 55) each defining a side wall of the storage cabinet (16), and a plurality of generally vertically oriented posts (40) extending from the base platform (62a). Each of the plurality of vertically oriented posts (40) has a slot (40a) for receiving an edge portion (45a, 50a, 55a) of one of the insulated panels (45, 50, 55) therealong. The slot (40a) may have a generally U-shaped profile that surrounds the edge portion (45a, 50a, 55a) of one of the insulated panels (45, 50, 55). At least one of the generally vertically oriented posts (40) has a channel (40c) that extends along a longitudinal dimension thereof, the channel (40c) being configured to receive one of insulation, tubing, or wiring of the freezer therethrough.

Abstract: A thermal energy storage system comprises a pressure vessel configured to withstand a first pressure, wherein the pressure vessel has a wall comprising an outer surface and an inner surface surrounding an interior volume of the pressure vessel. The interior volume of the pressure vessel has a first end in fluid communication with one or more compressors and one or more turbines, and a second end in fluid communication with at least one compressed air storage component. A thermal storage medium is positioned in the interior volume, and at least one reinforcement structure is affixed to the outer surface of the wall, wherein the at least one reinforcement structure configured to reinforce the wall to withstand a second pressure greater than the first pressure.

Abstract: A regenerator having a plurality of involute foils disposed in an annular gap between an inner cylindrical tube and an outer cylindrical tube. The involute shape of the foils provides uniform spacing throughout the entire regenerator and substantial surface area for fluid contact.

Abstract: A heat-exchange medium for use in a regenerative thermal oxidizer has a coating of potassium aluminum silicate which prevents the build-up of silicon dioxide from processed gas on the surface of the ceramic heat-exchange media.

Abstract: A cylindrical stainless steel housing includes an exhaust inlet collar and exhaust outlet collar allowing exhaust gas to travel therethrough at a mean flow velocity in accordance with a velocity formula. A plurality of stainless steel tubes extend through the housing from a steam inlet manifold to a steam outlet manifold. A number and size of the tubes is determined by formulas and dependent on an Euler number, a Reynolds number, a number of transfer units, a Prandtl number, a porosity factor and a system efficiency. The tubes may comprise an S-shape or a U-shape. The tube walls have a thickness determined according to wall thickness formulas and the walls include a plurality of cavities on an interior surface of each tube wall. The cavities may comprise a conical or semi-spherical shape and have a diameter determined according to formulas.

Abstract: A regenerator core for use in a gas turbine regenerator has integral manifold openings formed in the tube plates used to make up the core and has special reinforcing elements which provide high pressure containment in critical portions of the plate-and-fin heat exchanger construction. The reinforcing elements include a series of hoops of U-shaped cross section which are used to bridge the juncture lines of the heat exchanger manifolds. An outer channel region of the hoops is provided with a reinforcing strip of gusset material. The hoops with their reinforcing strips provide structural reinforcement in the region between the manifolds and the conventional side bar reinforcing members in the central core section.

Abstract: A spring assembly for use with a direct oxidation fuel cell system is provided. The spring assembly includes a pair of spring elements, placed over each of the major dimensions of the fuel cell, such that the top and bottom spring elements provide at least a portion of the load to the fuel cell for the required compression. The springs are designed to be fully compressed under the design pressure and are held in the compressed state by two side clamps thus providing a uniform planar pressure distribution across the fuel cell system. The spring elements each include several grooves formed therein extending towards center of the element. The side clamps include fastening members which are fingerlike extensions that fit within the grooves of the spring elements to hold the springs in tight engagement over the fuel cell system, with out bolts, pins or other fasteners.

Abstract: Microtubule encapsulated microcapsules of a phase-change material and preparation thereof are provided. The microcapsules of a phase-change material consist of a phase-change material, truncated microtubules, and a polymer. The truncated microtubules are formed by truncating hollow tubular natural fibers into fiber segments with a length of 0.1 mm-5 cm. The diameter of the hollow tubular natural fiber is 0.1-1000 ?m. The phase-change material is encapsulated in the truncated microtubules and the truncated microtubules are covered with the polymer. The microtubules have high energy storage density due to high hollowness, and can transfer energy stably due to the closed structure, transfer heat rapidly due to the very fine micro-tubular structures, and may be used for a long term in view of the heat and chemical stability.

Abstract: A thermal energy storage material (TESM) system (and associated methods) that reproducibly stores and recovers latent heat comprising i) at least one first metal containing material including at least one first metal compound that includes a nitrate ion, a nitrite ion, or both; ii) at least one second metal containing material including at least one second metal compound; and iii) optionally including water, wherein the water concentration if any is present is less than about 10 wt. %; wherein the TESM has a liquidus temperature, TL, from about 100° C. to about 250° C.; and wherein the TESM exhibits a heat storage density from 300° C. to 80° C. of at least about 1 MJ/l; so that upon being used in a system that generates heat, at least a portion of the heat is captured and stored by the TESM and subsequently released for use, and the system is generally resistant to corrosion at temperatures of about 300° C.

Abstract: Disclosed is an improved sealing element for a regenerative heat exchanging apparatus, such as a Ljungstrom™-type or other suitable regenerative heat exchangers. The sealing element can be mounted to a wall of the rotor of the heat exchanger to provide a secure seal between the wall and a housing of the heat exchanger, thereby inhibiting the leakage of gas between the hot gas conduit and cool air conduit of the regenerative heat exchanger. In one embodiment, the sealing element includes a base plate that is used to mount the sealing element to the wall. The sealing element also includes a contact shoe that maintains a sealing contact between the wall and housing. A flexible portion is coupled between the base plate and contact shoe to provide the sealing element with flexibility and resiliency so that the sealing element maintains contact with the sealing surface even when the heat exchanging apparatus experiences warping and/or distortion from thermal stress.

Abstract: A method for manufacturing a heat exchanger, including forming at least one flexible heat exchanging assembly with first and second adjacent conduits defined therein, shaping the flexible heat exchanging assembly, and heating the heat exchanging assembly to transform at least a portion of the flexible heat conducting material into a rigid heat conducting material.

Abstract: A reduced shedding regenerator and method are disclosed with regenerator surfaces to minimize shedding of particles from the regenerator thereby alleviating a source of potential damage and malfunction of a thermal regenerative machine using the regenerator.

Abstract: Appropriate amount of brazing material is put on each of inner and outer recessed portions of a first heat storing element. Then, the first heat storing element is placed close to and substantially parallel to a second heat storing element, and an inner projected portion of the second heat storing element is fitted into the inner recessed portion of the first heat storing element, and simultaneously an outer projected portion of the second heat storing element is fitted into the outer recessed portion of the first heat storing element.

Abstract: A cold and/or heat accumulator with a plurality of carrier elements (10) which are charged with a cold or heat storage medium, and with a heat exchanger (12) which is designed to have a heat transfer medium flow through it in order to cause heat exchange between the cold or heat storage medium and the heat transfer medium. The heat exchanger (12) has at least one serpentine hollow section (14), and at least at least one carrier element (10) is provided between the legs of at least some of the loops of the serpentine hollow section. In a process for producing the cold and/or heat accumulator, the height of the carrier elements is coordinated to a distance between the legs of the at least one loop such that, after a force-fit connection is formed between the serpentine hollow section and the carrier elements.

Abstract: An apparatus and method for cooling hot fluids, especially exhaust gases, with a multi-pass cooler core. The cooler core is particularly useful for cooling exhaust gases flowing in an exhaust gas recirculation (EGR) system or regime in operative association with an internal combustion engine, such as a diesel engine. Cooled gases are recirculated to the engine input to help reduce noxious exhaust emissions. The invention utilizes unequal areas-in-flow between the first exhaust pass through the core and the second and subsequent passes through the core. The first pass through the core features an area-in-flow comparatively larger than the area-in-flow of the second pass. The difference in areas-in-flow between passes influences gas velocities to reduce fouling, despite changes in exhaust gas temperature between passes through the core.

Abstract: A method of attaching an air duct to a recuperator core may include welding a pair of butterpasses along a length of each of a plurality of core portions, connecting the plurality of core portions to one another to form the recuperator core and a pair of butterpasses extending along a length of the recuperator core, and attaching the air duct to the recuperator core along at least a portion of the pair of butterpasses. The method may also include controllably moving a welding torch into the air duct and along substantially the length of the recuperator core and controllably welding each butterpass to the air duct along substantially the length of the recuperator core without adding metal to the weld.

Abstract: A joint connecting consecutive sheets of etched regenerator foil for a spiral-wrapped regenerator of a regenerative gas cycle machine such as a Stirling cycle engine or Stirling, pulse tube, or Gifford-McMahon cryocooler. The joint comprises a multiplicity of tabs on the end of one sheet of regenerator foil interlocked with a multiplicity of tabs on the end of another piece of regenerator foil. The joint is no thicker than the original thickness of the sheets of etched regenerator foil that it connects together, and the tabs substantially fill the holes into which they are locked, minimizing undesirable leakage through the joint after it has been incorporated in a regenerator.

Abstract: An apparatus for manufacturing a cell of a recuperator wherein the cell includes a plurality of primary surface sheets, a plurality of spacer bars and a pair of guide vanes. A fixture has a top portion and a bottom portion. The top portion is pivotably movable between an open or loading position and a closed or welding position. A plurality of the spacer bars, plurality of primary surface sheets and a pair of guide vanes are positioned in the fixture in a preestablished relationship and are fixedly attached one to another by a tack welding machine. A controller operative controls the tack welding machine.

Abstract: An inspection fixture and line is used to accurately determine the geometry and dimensional accuracy of a circular recuperator core. With the fixture and line inspection of a length, an inner diameter and an outer diameter of the circular recuperator core are completed. The method of using the fixture and the line further insures the concentricity of a donor inlet duct and a donor outlet duct.

Abstract: A system is disclosed to manufacture a recuperator core. The core is made up of a plurality of cells and an inner sealing member. A manufacturing system has an input end, an assembly station having a lower or inner chucking portion and an upper portion, and a welding station. The lower or inner chucking portion is movable between a lower position and an upper position and has a retracted position and an expanded position. The upper portion is movable between a loading position and a clamping position and is rotatable between a first position and a second position. The welding station performs a tack welding operation and a lineal welding operation.

Abstract: A method for aligning a circular core. The method has a work station which defines an inner chucking portion being movable between a lower position and an upper position and a retracted position and an expanded position. The work station defines an upper portion being movable between a first position and a second position and a loading position and a clamping position. The clamping position has a plurality of positions. The circular core being aligned during at least a portion of the plurality of positions. And, the work station having a welding station.

Abstract: An assembly line for economically and efficiently assembling a core into a recuperator. The assembly line has an inlet end, an assembly station, a welding station, a control station and an outlet end. The inlet end has a plurality of the cores to be used for assembly thereat. The core is positioned within the assembly station and an assembly fixture locates a ducting structure in a preestablished relationship to the core. The control station using a plurality of sensors sends an input to a controller and the welding station performs a weld fixedly securing the ducting structure to the core.

Abstract: A heating element is described for a regenerative heat exchanger that is constructed as a profiled steel sheet. The aim of the invention is to produce a heating element that is resistant to acids, has anti-soiling properties and, however, has a good thermal output. To these ends, the heating element is provided with an enameling, and a fluoroplastic coating is applied to the enameled surface.

Abstract: A regenerator for a thermal cycle engine and methods for its manufacture. The regenerator has a random network of fibers formed to fill a specified volume and a material for cross-linking the fibers at points of close contact between fibers of the network. A method for manufacturing a regenerator has steps of providing a length of knitted metal tape and wrapping a plurality of layers of the tape in an annular spiral.

Abstract: A system is disclosed to manufacture a recuperator core. The core is made up of a plurality of cells and an inner sealing member. A manufacturing system has an input end, an assembly station having a lower or inner chucking portion and an upper portion, and a welding station. The lower or inner chucking portion is movable between a lower position and an upper position and has a retracted position and an expanded position. The upper portion is movable between a loading position and a clamping position and is rotatable between a first position and a second position. The welding station performs a tack welding operation and a lineal welding operation.

Abstract: A system for aligning a circular core. The system has a work station which defines an inner chucking portion being movable between a lower position and an upper position and a retracted position and an expanded position. The work station defines has upper portion being movable between a first position and a second position and a loading position and a clamping position. The clamping position having a plurality of positions. The circular core being aligned during at least a portion of the plurality of positions. And, the work station having a welding station.

Abstract: An assembly line is disclosed for economically and efficiently assembling a core into a recuperator. The assembly line has an inlet end, an assembly station, a welding station, a control station and an outlet end. The inlet end has a plurality of the cores to be used for assembly thereat. The core is positioned within the assembly station and an assembly fixture locates a ducting structure in a preestablished relationship to the core. The control station using a plurality of sensors sends an input to a controller and the welding station performs a weld fixedly securing the ducting structure to the core.

Abstract: Recuperators include a core which is commonly constructed of a plurality of relatively thin flat sheets having an angled or corrugated spacer fixedly attached therebetween. The sheets are joined into cells, sealed and form passages between the sheets. These cells are stacked or rolled and form alternate air (recipient) cells and hot exhaust (donor) cells. Compressed discharged air from a compressor of the engine passes through the air cell while hot exhaust gas flows through alternate cells. The exhaust gas heats the sheets and the spacers, and the compressor discharged air is heated by conduction from the sheets and spacers. The need for repeatability of construction of each cell assures that the final recuperator is economically and easily assembled. Examples, of such repeatability required includes length, height, thickness, weld size, weld position, weld splatter and others.

Abstract: A method of manufacturing a recuperator for a gas turbine engine comprises the steps of stamping a plurality of spaced integral ribs on a metal plate so as to define a plurality of high pressure channels, stamping a plurality of spaced integral ribs on a second metal plate so as to define a plurality of low pressure channels, joining said first and second metal plates to form a cell, and joining a plurality of said cells to one another.

Abstract: A method of assembling a regenerator comprising multiple concentric layers of foil, each with an unbonded joint inside a generally cylindrical space, by inserting each successive layer of foil into the remaining space inside said generally cylindrical space and pressing it outward against the wall of the generally cylindrical space until its edges do not overlap.

Abstract: A method for adding additional axial seals and radial seals within existing air preheaters. The installed heat transfer baskets, radial seals, axial seals, and gratings are all removed from the air preheater. The existing stay plates are modified, if they are to be reused, or replaced with new stay plates. An intermediate diaphragm plate is positioned in each original compartment and mounted to the stay plates. Additional hot and cold end axial seal support bars are mounted to the rotor shell and intermediate diaphragm plate. Axial seals are installed on the original and additional axial seal support bars and radial seals are installed on the axial edges of the original and intermediate diaphragm plates. Finally, new heat transfer baskets are inserted into each of the compartments formed by the original diaphragm plates, the intermediate diaphragm plates, and the rotor shell.

Abstract: Recuperators include a core which is commonly constructed of a plurality of relatively thin flat sheets having an angled or corrugated spacer fixedly attached therebetween. The sheets are joined into cells, sealed and form passages between the sheets. These cells are stacked or rolled and form alternate air (recipient) cells and hot exhaust (donor) cells. Compressed discharged air from a compressor of the engine passes through the air cell while hot exhaust gas flows through alternate cells. The exhaust gas heats the sheets and the spacers, and the compressor discharged air is heated by conduction from the sheets and spacers. The need for repeatability of construction of each cell assures that the final recuperator is economically and easily assembled. Examples, of such repeatability required includes length, height, thickness, weld size, weld position, weld splatter and others.

Abstract: The invention related to a method in the manufacture of a plate heat exchanger (1), preferably a so-called recuperator. This has flow channels arranged between the plates, every other channel being designed to accommodate the flow of a heat-emitting medium and every second channel the flow of a heat-absorbing medium. The flow channels for one of the media, preferably the heat-absorbing medium, are connected in parallel to manifolds for the said medium. The plates also have a raised pattern designed to produce a counter-flow section and two cross-flow sections in the recuperator, one on either side of the counter-flow section, the cross-flow sections having a lower raised pattern height than the counter-flow section. By means of a punching and pressing operation openings (4′, 6′) are made in each plate, with side walls formed around the edges of the openings. Following a joining process, in which the side walls undergo pressure resistant jointing, the side walls from walls of the manifolds (4, 6).