Abstract: A device is provided for modifying the temperature of a breathing or other as supplied through a conduit. A heat exchanger is mounted in-line with the conduit. A thermoelectric device has first and second thermally conductive plates separated by at least one thermoelectric couple. The first thermally conductive plate is in thermal contact with the heat exchanger. A phase change material is in thermal contact with the second thermally conductive plate. A voltage is applied to the thermoelectric couple(s) to maintain the first and second thermally conductive plates at different temperatures. The phase change material changes from a first phase to a second phase at a phase change temperature that is selected to be between the different temperatures of the first and second thermally conductive plates.

Abstract: An improved heat pipe comprising a duct having disposed at opposite ends thereof an evaporator with wick-lined hollow fins in the form of extended corrugations thereon, and operable to supply heat to the evaporator comprised of a gas combustor having an internal volume for containing the evaporator and combustion air for supply to a combustion chamber located therein; a wick capable of transporting liquid by capillary action lining substantially all internal surfaces of said heat pipe; an external heat sink operable to remove heat from the condenser; and a heat transport medium contained by said heat pipe. The evaporator is further comprised of a coarse porous material lining and completely filling the spaces within the hollow fins open to the evaporator for increased structural stiffness and ease of fabrication; and a porous mass completely filling the evaporator for increased compressive strength.

Abstract: A heat exchanger with at least one main tube, closed off at one end, into which compressed air, which is to be heated, is admitted and, after being heated, is removed. The main tube has at least two channel guideways which are separated from one another in the longitudinal direction. U-shaped or curved compressed air lines project from the main tube and contact the hot gases. Each compressed air line is connected at one end to the channel guideway of the main tube into which compressed air is admitted, and at its other end with the channel guideway through which the heated compressed air is removed. The compressed air lines are formed primarily from hollow bodies, which extend in the direction of flow of the hot gas and which preferably are tapered at the inflow and outflow ends in order to aid the flow.

Abstract: Tube bundle heat exchanger of graphite, in which a multiplicity of graphite tubes are set into the tube sheets and are joined to the sheets by screw or cement joints, characterized by the feature that each tube is surrounded by at least one group of graphite fiber bundles, the latter are connected to the tube in a force-locking manner, and the distance of adjacent fiber bundles is five to ten times the diameter of the graphite fiber bundle.

Abstract: The invention contemplates an improved sandwich-type core construction for a heat exchanger, featuring light weight without sacrifice of the strength needed for handling elevated pressures. Passages of one set are interleaved with those of another set, using spaced parallel heat-transfer plates. Elongate parallel spacers extending in one direction establish, with their adjacent plates, flow passages of one system, while elongate parallel spacers extending in a different direction establish flow passage of a second system, between paired plates of the first system. The perimeter of the core at ends of at least one of the system passages establishes solid continuous seating for such system headers. Substantial weight saving, without sacrifice of strength, is achieved by depressed excavation of spacer material in regions thereof not involved in header-seating accommodation.

Abstract: The drawings and description disclose a radiator having top and bottom tanks with their respective headers, and a core assembly therebetween. The latter includes a group of fins and tubes, wherein each tube has a flattened, oblong body section, cylindrical end sections for connection with the respective headers, and transition sections between the flattened body and the cylindrical ends. Reinforcement means is provided for preventing collapsing or pinching at the ends of the flattened body section due to stressing of the tube or flexing of the headers. The reinforcement means is in the form of various shaped pairs of outwardly extending reinforcement ribs formed on opposite sides of the transition section, or inwardly extending dimples formed on opposite sides of the flattened body section adjacent the transition section.

Abstract: In a radiator having flat tubes arranged in parallel and connected to header pipes for feed and return flow, each flat tube has two connection bores near the front end thereof. To enable the radiator to be manufactured by the use of pressure welding, a support part, angled into U-form with two bent ends arranged coaxially with the two connection bores, is inserted into each flat tube. These ends of the support part prevent the flat tube from being pressed inwardly during pressure welding. The portion of the support part extending parallel with the end edge of the flat tube is welded to the tube end edge, so that the support part simultaneously also forms the end closure wall of the flat tube.

Abstract: A heat exchanger comprises a stack of spaced plates such that elongate plane-parallel fluid-conduit systems are established between adjacent pairs of plates, the plane-parallel conduit systems being in two sets, with the conduit system of one set being interposed between two conduit systems of the other set. Between adjacent plates, a conduit system is closed along its two laterally opposite edges, by rail-like spacers between the involved adjacent plates. The conduit system of at least one set comprises corrugated structures taking the form of extruded sections and having ridges which are connected to the lateral-edge closures of the involved conduit system.

Abstract: A heat exchanger core assembly adaptable for allowing the passage of air therethrough comprising a plurality of fin elements extending in spaced apart parallel fashion across a plurality of fluid carrying tube members, each of the fin elements being positioned within the core assembly so as to have opposite side edges extending in a direction substantially parallel to the direction of air flow through the core assembly, each fin element including a folded over side portion extending along each of the opposite side edges thereof, the fin elements being stackable one upon the other such that the folded over side portions of one fin element mate with the folded over side portions of an adjacent fin element thereby forming a continuous, uninterrupted, substantially air tight core side on each opposite side of the plurality of mated together fin elements for substantially preventing the leakage of air therethrough.