Abstract: A hydrogen generator is formed of a strip of corrugated material that has been folded back and forth upon itself to define a monolith having multiple fluid flow regions. At least one of these regions is used for combustion, and at least one of these regions is used for steam reforming. Water is introduced into another fluid flow region, so as to receive heat from products of combustion, and to be converted into steam. The steam is directed into one or more regions used for steam reforming, so as to produce hydrogen for use in a fuel cell. In its more general form, the invention includes a compact heat exchanger, formed of a strip of corrugated material that has been folded back and forth upon itself, the heat exchanger being capable of transferring heat among three or more fluid streams.

Abstract: A low-cost, high-temperature heat exchanger is made from a notched piece of metal, the metal being folded back and forth upon itself to form a monolith. The notches in the metal piece create openings, communicating with distinct sides of the monolith. Ducts are attached to the openings. Cut pieces of corrugated metal, which may have a catalyst coating, are inserted between folds of the monolith. The heat exchanger may be used as part of a fuel cell system, or in other industrial applications, to recover waste heat, or to conduct various catalytic and non-catalytic reactions. The invention also includes an element, or building block, for a high-temperature heat exchanger, including a folded metal monolith with metal combs inserted, the monolith and the combs defining seams which are hermetically sealed.

Abstract: A low-cost, high-temperature heat exchanger is made from a notched piece of metal, the metal being folded back and forth upon itself to form a monolith. The notches in the metal piece create openings, communicating with distinct sides of the monolith. Ducts are attached to the openings. Cut pieces of corrugated metal, which may have a catalyst coating, are inserted between folds of the monolith. The heat exchanger may be used as part of a fuel cell system, or in other industrial applications, to recover waste heat, or to conduct various catalytic and non-catalytic reactions. The invention also includes an element, or building block, for a high-temperature heat exchanger, including a folded metal monolith with metal combs inserted, the monolith and the combs defining seams which are hermetically sealed.

Abstract: A compact steam reformer produces hydrogen to power a fuel cell, such as can be used in a vehicle. The steam reformer includes a first channel, at least partly coated with a steam reforming catalyst, and a second channel, at least partly coated with a combustion catalyst, the channels being in thermal contact with each other. Heat from the combustion is used in the steam reforming reaction. In another embodiment, the gas streams feeding the reforming and combustion channels pass through a valve which reverses the gas streams periodically. The combustion channel becomes the reforming channel, and vice versa, so that carbon deposits in the former reforming channel are burned off. This arrangement enables the reforming reaction to continue indefinitely at peak efficiency.

Abstract: A catalytic reactor or heat exchanger includes a monolith defining a plurality of leaves, the monolith having a generally annular cross-section. The monolith is disposed within a generally cylindrical outer tube, and around a corrugated inner tube. The reactor includes a device for urging the monolith radially outward, so as to maintain contact between the monolith and the outer tube. Such device may include a coned washer, or it may be defined by a folded flap that is integral with the inner tube. In either case, the reactor compensates for metal creep, and virtually insures continued contact between the monolith and the outer tube.

Abstract: A heat exchanger is formed of a strip of corrugated material that is folded back and forth upon itself to define a stack. Cut pieces of corrugated material are inserted within the folds of the strip, such that the corrugations of the cut pieces are generally perpendicular to the corrugations of the folded strip. A set of duct attachments holds the assembly together, and provides paths for fluid flowing into and out of the exchanger. The ends of the stack, and those parts of the sides that are not spanned by the duct attachments, are sealed with a high-temperature sealant. The sealant is preferably a moldable material that is applied and allowed to harden, and which has a coefficient of thermal expansion that approximates that of the stack. The heat exchanger is easy and inexpensive to manufacture, but is suitable for use in high-temperature applications.

Abstract: A reactor includes a plurality of metal leaves which extend from an interior of the reactor to its exterior. The leaves occupy a space between an internal mandrel and an external tube. In one embodiment, the leaves are generally flat pieces of foil, stacked together so that they do not touch except at spacers formed in the pieces. In another embodiment, the leaves are formed of a pleated and crimped foil, each leaf being defined by a piece of foil that has been folded over upon itself. In both embodiments, the leaves extend from the internal mandrel, radially outward to an inner surface of the tube. The reactor facilitates the transfer of heat between the outside of the reactor and its inside region.

Abstract: A reactor cartridge includes a plurality of spaced-apart monoliths, formed along a tube or other mandrel. Each monolith is formed of a pair of flat and corrugated metal strips, spirally wound around the tube. These strips could be made of solid or screen material. The corrugations are skewed, such that the monolith imparts a swirl to gases flowing through it. The corrugations of the strips in adjacent monoliths are oriented differently, so that successive monoliths impart different swirls to the gases, so as to promote mixing of gases and better heat transfer from the exterior to the interior of the cartridge. An insertion and removal tool simplifies the procedure for stacking such cartridges in a long pipe, or for removing cartridges from the pipe. The all-metal construction facilitates heat transfer through the entire reactor, and avoids the problems associated with packed ceramic beds.

Abstract: A reactor cartridge includes a plurality of spaced-apart monoliths, formed along a tube or other mandrel. Each monolith is formed of a pair of flat and corrugated metal strips, spirally wound around the tube. These strips could be made of solid or screen material. The corrugations are skewed, such that the monolith imparts a swirl to gases flowing through it. The corrugations of the strips in adjacent monoliths are oriented differently, so that successive monoliths impart different swirls to the gases, so as to promote mixing of gases and better heat transfer from the exterior to the interior of the cartridge. An insertion and removal tool simplifies the procedure for stacking such cartridges in a long pipe, or for removing cartridges from the pipe. The all-metal construction facilitates heat transfer through the entire reactor, and avoids the problems associated with packed ceramic beds.

Abstract: A reactor cartridge includes a plurality of spaced-apart monoliths, formed along a tube or other mandrel. Each monolith is formed of a pair of flat and corrugated metal strips, spirally wound around the tube. These strips could be made of solid or screen material. The corrugations are skewed, such that the monolith imparts a swirl to gases flowing through it. The corrugations of the strips in adjacent monoliths are oriented differently, so that successive monoliths impart different swirls to the gases, so as to promote mixing of gases and better heat transfer from the exterior to the interior of the cartridge. An insertion and removal tool simplifies the procedure for stacking such cartridges in a long pipe, or for removing cartridges from the pipe. The all-metal construction facilitates heat transfer through the entire reactor, and avoids the problems associated with packed ceramic beds.

Abstract: A fuel cell system includes a fuel cell stack, a reformer which is thermally integrated with the fuel cell stack. The system may also include a combustor which is thermally integrated with the reformer. The reformer is a reformation catalyst containing channel bounded by at least one corrugated foil wall. The reformer is adapted to reform a hydrocarbon fuel to a hydrogen containing reaction product and to provide the reaction product to the fuel cell stack.

Abstract: A catalytic combustor is formed from a stack of flat and corrugated metal strips. The stack may or may not be wound into a spiral or formed into some other curved structure. Some of the strips are displaced, or offset, relative to other strips, such that some strips do not extend as far as the end faces of the stack. The latter feature increases the effective height of the corrugations, at the end faces, and makes it feasible to weld the strips together. In one embodiment, there are high-amplitude corrugated strips and low-amplitude corrugated strips. The low-amplitude corrugated strips increase the effective cell density, but are displaced from the end faces of the stack so as to permit convenient welding. The resulting combustors therefore have very high cell density, yet can be manufactured economically.

Abstract: A monolith for imparting swirl to a gas stream includes a stack of alternating flat and corrugated strips defining channels for gas flow. The strips are attached, at an angle, to a carrier. Also, the corrugations of the corrugated strips may be skewed. The carrier defines a cylindrical shell for the strips, and the strips extend from the carrier to a central region. The strips are curved, typically having substantially the shape of involutes, and substantially fill the space between the central region and the shell. Due to the angle of attachment between the strips and the carrier, the gas flow channels are oriented in different directions, at different locations on the outlet face of the monolith. This structure therefore imparts swirl to gas flowing through the monolith.

Abstract: A catalyst support is formed of a monolith having corrugated metal leaves. The corrugations of each leaf are oblique relative to the edges of the leaf. Each leaf extends from an interior region to an exterior region, and has corrugations that are non-parallel to the corrugations in an adjacent leaf. Each leaf also includes slits, and is coated with a suitable catalyst. A set of monoliths, made as described above, are stacked within a cylindrical pipe. The corrugations define gas flow channels, which enable heat applied to the exterior of the pipe to travel to the center of the monolith, and back to the outside. The support of the present invention thus facilitates heat transfer to essentially all regions of the monolith. The invention also inherently overcomes the problem associated with thermal mismatch between the metal pipe and a ceramic catalyst material.

Abstract: A hydrogen generator is formed of a strip of corrugated material that has been folded back and forth upon itself to define a monolith having multiple fluid flow regions. At least one of these regions is used for combustion, and at least one of these regions is used for steam reforming. Water is introduced into another fluid flow region, so as to receive heat from products of combustion, and to be converted into steam. The steam is directed into one or more regions used for steam reforming, so as to produce hydrogen for use in a fuel cell. In its more general form, the invention includes a compact heat exchanger, formed of a strip of corrugated material that has been folded back and forth upon itself, the heat exchanger being capable of transferring heat among three or more fluid streams.

Abstract: A heat exchanger is formed of a strip of corrugated material that is folded back and forth upon itself to define a stack. Cut pieces of corrugated material are inserted within the folds of the strip, such that the corrugations of the cut pieces are generally perpendicular to the corrugations of the folded strip. A set of duct attachments holds the assembly together, and provides paths for fluid flowing into and out of the exchanger. The ends of the stack, and those parts of the sides that are not spanned by the duct attachments, are sealed with a high-temperature sealant. The sealant is preferably a moldable material that is applied and allowed to harden, and which has a coefficient of thermal expansion that approximates that of the stack. The heat exchanger is easy and inexpensive to manufacture, but is suitable for use in high-temperature applications.

Abstract: A catalytic combustor for a gas turbine includes a stack of metal strips, each strip having an inlet end and an outlet end. The inlet ends of both sides of the strip are uncoated, to limit the temperature and maintain rigidity of the strip at the inlet end. In one embodiment, both sides of the strip have a light-off band, coated with catalyst, and adjacent to the uncoated inlet band. One side of the strip (Side A) also includes at least one combustion band, while the other side (Side B) has no corresponding coated band. The strips are arranged such that Side A of a given strip inside the stack faces Side A of an adjacent strip, and Side B of a strip inside the stack faces Side B of an adjacent strip. The resulting structure prevents overheating of the combustor, maintains its rigidity, and reduces the pressure drop through the combustor.

Abstract: A heat exchanger is made from a single piece of metal foil. The foil is coated with catalyst, corrugated with herringbone or skew corrugations, except along narrow flat areas near its edges, and folded back and forth upon itself. The folded metal structure is blocked off, except at regions near the flat areas, and enclosed in a container. A first gas stream flows into one set of folds, in a path which includes the flat areas and the channels formed by the corrugations. A second gas stream similarly flows into the other set of folds. The two streams are in thermal contact, but do not mix. The heat exchanger is especially useful in operating a catalytic fuel reformer, or in other applications involving catalytic processes. Alternative embodiments use straight corrugations to create straight channels that minimize the pressure drop through the heat exchanger.

Abstract: A catalytic combustor includes a plurality of channels formed by corrugated and flat strips, some of the channels being coated with a catalyst and others being uncoated. In the vicinity of the inlet end of the combustor, the boundary of each coated channel has a thermal barrier, to inhibit the flow of heat from the coated channel to an adjacent uncoated channel. Also in the vicinity of the inlet end, the coated channels may include one or more additional coated members, to enhance catalytic combustion in the light-off zone. The combustor of the present invention lights off at a relatively low temperature, and quickly reaches a stabilized and controlled operating temperature.

Abstract: A heat exchanger is made from a single piece of metal foil. The foil is coated with catalyst, corrugated with herringbone or skew corrugations, except along narrow flat areas near its edges, and folded back and forth upon itself. The folded metal structure is blocked off, except at regions near the flat areas, and enclosed in a container. A first gas stream flows into one set of folds, in a path which includes the flat areas and the channels formed by the corrugations. A second gas stream similarly flows into the other set of folds. The two streams are in thermal contact, but do not mix. The heat exchanger is especially useful in operating a catalytic fuel reformer, or in other applications involving catalytic processes. Alternative embodiments use straight corrugations to create straight channels that minimize the pressure drop through the heat exchanger.