Abstract: An evaporator comprises a plurality of thermal elements disposed in a shell interior of an evaporator shell. A primary supply line configured to carry a working fluid is disposed in the shell interior. A plurality of tube sets is fluidically coupled to the primary supply line, and each tube set is spaced apart from an adjacent tube set along the first primary supply line. Each tube set comprises a plurality of individual tubes, with each tube proximate a different subset of thermal elements within the shell interior. Each tube comprises a plurality of first fluid distribution points configured to distribute the working fluid proximate the external surface of at least one of the plurality of thermal elements, thereby increasing the amount of surface area of the thermal elements in contact with the working fluid, and increasing the overall efficiency of the evaporator.

Abstract: An evaporator comprises a plurality of thermal elements disposed in a shell interior of an evaporator shell. A primary supply line configured to carry a working fluid is disposed in the shell interior. A plurality of tube sets is fluidically coupled to the primary supply line, and each tube set is spaced apart from an adjacent tube set along the first primary supply line. Each tube set comprises a plurality of individual tubes, with each tube proximate a different subset of thermal elements within the shell interior. Each tube comprises a plurality of first fluid distribution points configured to distribute the working fluid proximate the external surface of at least one of the plurality of thermal elements, thereby increasing the amount of surface area of the thermal elements in contact with the working fluid, and increasing the overall efficiency of the evaporator.

Abstract: A process of producing shell and tube heat exchangers where the ends of the tubes are secured to a tube sheet while reacting applied FSW forces without introducing a crevice or local deformation near the ends of the tubes. In particular, an interference fit is used to lock the ends of the tubes into the tube sheet without flaring or expanding the tube ends. A FSW process is then used to weld the ends of the tubes to the tube sheet.

Abstract: A heat exchanger is disclosed. The heat exchanger includes a heat exchange member that includes a first extruded member having a first end and a second end. The first extruded member forms a plurality of fluid passages that are in fluid communication with the first end of the first extruded member and the second end of the first extruded member. At least one of the fluid passages is an inlet fluid passage and at least one of the fluid passages is an outlet fluid passage. A plug is fixedly coupled to the second end of the first extruded member. The plug forms a plug fluid passage that fluidically interconnects the inlet fluid passage at the second end of the first extruded member with the outlet fluid passage at the second end of the first extruded member.

Abstract: A process of producing shell and tube heat exchangers where the ends of the tubes are secured to a tube sheet while reacting applied FSW forces without introducing a crevice or local deformation near the ends of the tubes. In particular, an interference fit is used to lock the ends of the tubes into the tube sheet without flaring or expanding the tube ends. A FSW process is then used to weld the ends of the tubes to the tube sheet.

Abstract: A hybrid plate-fin heat exchanger for exchanging heat between a first fluid and a second fluid is disclosed. The hybrid plate-fin heat exchanger comprises a plurality of plates, each of which comprises channels for conveying the first fluid. Fins are brazed onto each plate, wherein the fins define a plurality of flow channels for the second fluid. The plates are joined to one another via friction-stir welding in such a way that the brazed regions are fluidically isolated from the first fluid during operation. As a result, the heat exchanger is suitable for use in applications that use a first fluid, such as seawater or geothermal fluid, which is corrosive for the brazed regions.

Abstract: A heat exchanger comprising a plurality of plates that are demountably attached to a frame is disclosed. Each plate comprises a plurality of channels for conveying a primary fluid through the heat exchanger. The frames are arranged in the frame so that spaces between adjacent frame pairs define conduits for conveying a secondary fluid through the heat exchanger. The plates are mounted in the frame so that they can be individually removed from the frame. Further, each of the channels is fluidically connected to input and output ports for the primary fluid by detachable couplings. As a result, heat exchangers in accordance with the present invention are more easily repaired or refurbished than prior-art heat exchangers.

Abstract: A process of producing shell and tube heat exchangers where the ends of the tubes are secured to a tube sheet while reacting applied FSW forces without introducing a crevice or local deformation near the ends of the tubes. In particular, an interference fit is used to lock the ends of the tubes into the tube sheet without flaring or expanding the tube ends. A FSW process is then used to weld the ends of the tubes to the tube sheet.

Abstract: A process of producing shell and tube heat exchangers where the ends of the tubes are secured to a tube sheet while reacting applied FSW forces without introducing a crevice or local deformation near the ends of the tubes. In particular, an interference fit is used to lock the ends of the tubes into the tube sheet without flaring or expanding the tube ends. A FSW process is then used to weld the ends of the tubes to the tube sheet.

Abstract: A heat-exchanger module that conveys a fluid through one or more heat exchangers with little or no pressure drop is presented. The heat-exchanger module comprises a first manifold that smoothly channels the fluid from a fluid source to each of the heat exchangers. The heat-exchanger module further comprises a second manifold that smoothly channels the fluid from the heat exchangers to a fluid sink. The manifolds are dimensioned and arranged to mitigate development of pressure drops in the fluid flow.

Abstract: A process of producing shell and tube heat exchangers where the ends of the tubes are secured to a tube sheet while reacting applied FSW forces without introducing a crevice or local deformation near the ends of the tubes. In particular, an interference fit is used to lock the ends of the tubes into the tube sheet without flaring or expanding the tube ends. A FSW process is then used to weld the ends of the tubes to the tube sheet.

Abstract: A heat exchanger comprising helically wound tube bundles is disclosed. The helically wound tube bundles are joined with tube sheets to define a primary working fluid system that is fluidically isolated from a secondary working fluid system. The tube sheets and tubes are formed of the same material, which facilitates their joining by means of joints that are substantially galvanic corrosion-resistant joints.

Abstract: An evaporator comprises a plurality of thermal elements disposed in a shell interior of an evaporator shell. A primary supply line configured to carry a working fluid is disposed in the shell interior. A plurality of tube sets is fluidically coupled to the primary supply line, and each tube set is spaced apart from an adjacent tube set along the first primary supply line. Each tube set comprises a plurality of individual tubes, with each tube proximate a different subset of thermal elements within the shell interior. Each tube comprises a plurality of first fluid distribution points configured to distribute the working fluid proximate the external surface of at least one of the plurality of thermal elements, thereby increasing the amount of surface area of the thermal elements in contact with the working fluid, and increasing the overall efficiency of the evaporator.

Abstract: A heat exchanger comprising helically wound tube bundles is disclosed. The helically wound tube bundles are joined with tube sheets to define a primary working fluid system that is fluidically isolated from a secondary working fluid system. The tube sheets and tubes are formed of the same material, which facilitates their joining by means of joints that are substantially galvanic corrosion-resistant joints.

Abstract: A heat exchanger comprising helically wound tube bundles is disclosed. The helically wound tube bundles are joined with tube sheets to define a primary working fluid system that is fluidically isolated from a secondary working fluid system. The tube sheets and tubes are formed of the same material, which facilitates their joining by means of joints that are substantially galvanic corrosion-resistant joints.

Abstract: Shell-and-tube heat exchangers that utilize one or more foam heat transfer units engaged with the tubes to enhance the heat transfer between first and second fluids. The foam of the heat transfer units can be any thermally conductive foam material that enhances heat transfer, for example graphite foam. These shell-and-tube heat exchangers are highly efficient, inexpensive to build, and corrosion resistant. The described heat exchangers can be used in a variety of applications, including but not limited to, low thermal driving force applications, power generation applications, and non-power generation applications such as refrigeration and cryogenics. The foam heat transfer units can be made from any thermally conductive foam material including, but not limited to, graphite foam or metal foam. In an embodiment, the heat exchanger utilizes tubes that are twisted around a central foam heat transfer unit.

Abstract: A spar platform comprises one or more continuous-fiber composite tubes fabricated at or near the intended site use of the platform. In some embodiments, the spar platform includes a relatively longer central tube and relatively shorter peripheral tubes. In some other embodiments, the spar platform is a single long tube. In some embodiments, the spar platform supports a wind turbine assembly. The continuous-fiber composite tubes are formed, in either a vertical or horizontal orientation, using a modified vacuum assisted resin transfer molding process.

Abstract: A heat exchanger module for thermally coupling a first fluid and second fluid is disclosed. The heat exchanger module comprises a plurality of heat exchangers, each of which is fluidically coupled to a common seawater inlet and a common seawater outlet. The heat exchanger module is dimensioned and arranged for integrating with an OTEC system located on an offshore platform that is deployed in a body of water. The heat exchanger module physically and fluidically couples with ports included in pontoons attached to the offshore platform. The ports are individually controllable so that the module can be added or removed from the OTEC system without interrupting operation of other heat exchanger modules integrated with the OTEC system.

Abstract: Heat exchangers are described that employ fins made of a heat conducting foam material to enhance heat transfer. The foam fins can be used in any type of heat exchanger including, but not limited to, a plate-fin heat exchanger, a plate-frame heat exchanger or a shell-and-tube heat exchanger. The heat exchangers employing foam fins described herein are highly efficient, inexpensive to build, and corrosion resistant. The described heat exchangers can be used in a variety of applications, including but not limited to, low thermal driving force applications, power generation applications, and non-power generation applications such as refrigeration and cryogenics. The fins can be made from any thermally conductive foam material including, but not limited to, graphite foam or metal foam.

Abstract: A process of producing shell and tube heat exchangers where the ends of the tubes are secured to a tube sheet while reacting applied FSW forces without introducing a crevice or local deformation near the ends of the tubes. In particular, an interference fit is used to lock the ends of the tubes into the tube sheet without flaring or expanding the tube ends. A FSW process is then used to weld the ends of the tubes to the tube sheet.