Abstract: A heat pipe comprising an elongated sealed metallic envelope having at least a pair of longitudinal channels extending along the length thereof. One of the channels is for the circulation of the vapor phase of the working medium in operation and the other for the liquid phase and capillary means are provided to furnish fluid communication therebetween. Dedicated vapor and liquid channels result in low viscous pressure drops, the capillary communication means and circumferential grooving in the vapor channel provide high capillary pressure differences, and circumferential grooving is provided to furnish the high evaporation and condensation film coefficients required. To support higher heat fluxes, wicking can be used to augment the capillary flow from the liquid channel. To support higher evaporator heat flux without the need for wicking means, the heat pipe can be provided with more than one liquid channel, each communicating with the vapor channel by capillary means.

Abstract: A unit for recovering thermal energy which utilizes a plurality of unique heat pipes, and the method and apparatus for fabricating the heat pipes is disclosed. The heat pipes are disposed horizontally and are filled with a volume of working fluid sufficient to cause the liquid phase to travel in either direction by gravity. Circumferential capillary grooves in the side walls of the heat pipes transport the liquid phase vertically above the liquid level to increase the area of the liquid-vapor interface. Additionally, the solid metal strips which form the grooves provide a low impedance thermal path from the walls of the heat pipe to the liquid-vapor interface where evaporation and condensation occur. These two factors significantly increase the efficiency of the system. A divider plate having an X-shaped cross section separates the liquid phase from the high velocity vapor phase to prevent slugging under high energy transfer conditions.

Abstract: A heat pipe capillary wick constructed from a sintered metal cylinder formed in close contact with the inner diameter of the heat pipe casing, and containing longitudinal grooves on the wick's inner surface, adjacent to the vapor space. The grooves provide longitudinal capillary pumping while the high capillary pressure of the sintered wick provides liquid to fill the grooves and assure effective circumferential distribution of liquid in the heat pipe.

Abstract: Apparatus for heat transfer is disclosed. This apparatus is a closed container which is possessed of an input portion and an output portion for heat energy and is provided on the inside thereof with a wick extending throughout from the input portion to the output portion and disposed so that the resistance offered thereby to the flow of liquid gradually decreases from the input side to the output side. The heat medium which is vaporized on the input side is moved in the direction of the output side by virtue of the difference of pressure created inside the container. The heat medium which is deprived of heat and consequently liquefied on the output side is moved within the wick in the direction of the input side by virtue of capillary action coupled with the suction resulting from the vaporization of the heat medium in the input portion.

Abstract: Radial projections are formed at opposed ends of a double walled hollow cylinder which form a vapor condensation chamber such that the radially outer wall is heated by means of vapors condensing thereon. Heating elements are mounted at the annular compartments and a steel wool packing is carried within each compartment and extends in a continuous annular manner throughout each compartment to distribute vaporizable liquid by the steel wool packing for effective vaporization as a result of energization of the heating elements.

Abstract: A thermal transfer system comprising a closed, generally horizontally disposed tubular envelope having heat transfer fins mounted at axially spaced points along its outer surface is disclosed. The interior surface of the tubular envelope has a large number of small circumferentially extending capillary grooves characterized by a restricted opening relative to the base of the grooves. A liquid phase/vapor phase working fluid is contained within the envelope with the liquid phase normally comprising about 50 to about 75 percent of the volume of the envelope at normal operating temperatures. A liquid phase return tube rests on the bottom of the envelope and is open at both ends. The liquid phase return tube has an inside diameter of about 30 to about 40 percent of the inside diameter of the tubular envelope and has a length of between about 65 percent and about 85 percent of the length of the envelope.

Abstract: A wick system is disclosed comprising a casing, a wall capillary and a mesh screen wick having at least one artery structure used in conjunction with a closed or open system while in contact with the wall capillary. The wick system may be used in a vertical or inclined position with a condenser at the top.

Abstract: The present invention comprises (1) a heat source, (2) a heat pipe, and (3) a thermal transformer in thermal contact with said heat pipe and proximately disposed to said heat source, whereby a uniform heat transfer from said heat source to a heating system is obtained. The thermal transformer includes (1) a container, (2) a working fluid and its vapor which are essentially in equillibrium, (3) evaporating surfaces depending from the internal surfaces of the transformer that are wetted with the working fluid and that are proximate to the heat source, and (4) condensing surfaces depending from the exterior of those areas of said heat pipe that are in thermal contact with said transformer.

Abstract: Apparatus for evaporating liquids, including means to form the liquid into a thin film on a heatable wall, the means comprising a porous layer having a first portion which covers the wall concerned and at the top of the wall passes via a bend into a second portion which is spaced from the first portion and is surrounded by a liquid-receptacle.

Abstract: The invention contemplates a heat-transfer device or heat pipe characterized by integral screen-wick structure providing relatively great contact area between the internal working fluid or condensable medium and the heat input.

Abstract: An electric heater is disposed horizontally along the free level of heat medium liquid within a vapor chamber, said electric heater being surrounded by a layer of porous material with void therebetween so that the heat medium liquid arises by capillary action and a thin film of the heat medium liquid formed in the void in the state of face contact to the electric heater is heated and vaporized. The lower portion of the porous material layer being immersed in the heat medium liquid and the other portion of it being exposed above the free level of the heat medium liquid thus the vapored heat medium fills the vapor chamber immediately.

Abstract: A heat pipe is provided with an internally positioned heat source.

Abstract: A heat pipe comprising a hermetically sealed hollow body which is filled with a saturated vapor of and a small amount of the condensate of a heat carrying fluid. The heat pipe communicates with the inside of an auxiliary body which also may contain a small amount of the condensate and vapor and which has associated therewith heat sink and heat source means by which the amount of vapor in the auxiliary body and in the hollow body may be regulated to control heat flow in the heat pipe.