The invention relates to a heat exchanger for an EGR (Exhaust Gas Recirculation) system, comprising a tube bundle of flat tubes, configured by combining two plates incorporating specific protrusions distributed according to the direction of the tube. These protrusions in both plates are in contact with one another or attached such that they establish internal channels. The present invention is characterized by the presence of either transverse projections or of transverse deviations generating disturbances in the flow through side walls of the internal channels, increasing the turbulence of the flow through said channels and thereby increasing heat exchange by convection.

A passive thermal system for use in a satellite and other aerospace applications includes a container having a heat-pipe working fluid disposed in a first chamber and a Phase Change Material (PCM) disposed in a second chamber that substantially surrounds the first chamber. The first chamber contains a wick for transporting the heat-pipe working fluid. The exterior of the first chamber has fins, etc., that extend into the PCM for heat spreading and increased interface area.

A flow heater is described that has a housing in which a flow channel extends from a liquid inlet to a liquid outlet. The heater has a metal plate along which the flow channel runs, and the metal plate carries a heating resistor. Provision is made for the metal plate to carry a corrugated sheet that protrudes into the flow channel and has openings through which the liquid that is to be heated can pass.

A water purification system can include an enclosed chamber having an evaporation region and a condensation region. The evaporation region can include an evaporation tower with a series of shelves to receive and increase a surface area of impure water while cascading downward from an upper shelf to lower shelves therebeneath as water evaporates therefrom to form water vapor within the enclosed chamber, and a fluid directing assembly to cyclically transport the impure water from a reservoir source to the upper shelf. The condensation region can include a purified water-receiving vessel and a plurality of water collectors. Individual water collectors of the plurality of water collectors can include an exterior surface coolable to a temperature below a dew point of air carrying the water vapor and shaped to channel water formed thereon by condensation to the purified water-receiving vessel.

To increase a heat exchange capacity of an indoor heat exchanger without increasing a pressure loss inside tubes of an outdoor heat exchanger. A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger 10 constituted by a plurality of heat transfer tubes 12A, which have a spiral grooves 13A formed with a predetermined lead angle Ra on inner faces of the tubes and are made to pierce a plurality of fins 11, and an outdoor machine equipped with an outdoor heat exchanger 20 constituted by a plurality of heat transfer tubes 22A which have a lead angle Rb of spiral grooves 23A smaller than that of a heat transfer tubes 10A used for the indoor heat exchanger 10 and are made to pierce a plurality of fins 11.

A heat exchange device includes a first section and a second section. Each of the first and second sections include flow passages configured for heat exchange between hot fluid within the flow passages and cold fluid external of the flow passages. Each of the flow passages having cold fluid flow therebetween. A separator is positioned dividing the cold fluid flow between flow passages. The separator includes two separator sheets spaced apart with a pillar matrix structurally connecting the separator sheets configured to prevent cold fluid mixing.

To increase a heat exchange capacity of an indoor heat exchanger without increasing a pressure loss inside tubes of an outdoor heat exchanger. A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger 10 constituted by a plurality of heat transfer tubes 12A, which have a spiral grooves 13A formed with a predetermined lead angle Ra on inner faces of the tubes and are made to pierce a plurality of fins 11, and an outdoor machine equipped with an outdoor heat exchanger 20 constituted by a plurality of heat transfer tubes 22A which have a lead angle Rb of spiral grooves 23A smaller than that of a heat transfer tubes 10A used for the indoor heat exchanger 10 and are made to pierce a plurality of fins 11.

A condensation enhancement heat transfer pipe that includes an optical pipe section, a fin section, and a transition section connecting the optical pipe section and the fin section. The outer surface of the fin section includes a plurality of individual fins, each having an acute shape of zigzag and forms an angle relative to the axial direction, an axial fin channel forms between the two adjacent ones of said individual fins along the axial direction, a peripheral fin channel forms between the two adjacent ones of said individual fins along the peripheral direction, an end, which is distributed along said axial direction, of each of said individual fins includes platforms, the fin side walls are connected with the platform by an arc, and the platforms are parallel to each other along the peripheral direction.

Vapor flow-diverting devices that re-direct upwardly flowing vapor, for example, in a downward direction across condenser tubes disposed in the upper or top section of a vapor-liquid contacting apparatus, are described. These devices are particularly beneficial in tubular condensers within distillation columns and may be used in combination with other associated equipment (e.g., a deflector plate and divider plate) as well as in combination with the tube surface enhancements to improve the heat transfer coefficient.

A heat exchanger is constituted by an indoor machine equipped with an indoor heat exchanger constituted by a plurality of heat transfer tubes, which have spiral grooves formed with a predetermined lead angle on inner faces of the tubes and are made to pierce a plurality of fins, and an outdoor machine equipped with an outdoor heat exchanger constituted by a plurality of heat transfer tubes which have a lead angle of spiral grooves smaller than that of a heat transfer tubes used for the indoor heat exchanger and are made to pierce a plurality of fins.