Abstract: A thermionic electric converter module integrated with heating and cooling heat pipes. Two heat pipes are arranged concentrically, with the annular emitter heat pipe on the outside of the module to isothermally distribute heat from a source located in any direction around the unit to the emitter located on the inside exterior wall of the heat pipe. The exterior wall surface of the collector heat pipe, located inside the annular emitter heat pipe, is separated from the emitter by the thermionic converter's interelectrode gap and serves as the collector of the thermionic converter. The collector heat pipe is of conventional cylindrical configuration and transports the waste heat of the thermionic converter along the unit's axis to a remote location for disposal.

Abstract: A heat pipe which maintains a controlled temperature gradient over its length. An annular heat pipe is constructed to have a core area which is a working furnace and to have the heat input at one end and a heat sink at the other end of the annular structure. The core is surrounded by an annular vapor space with a restricted cross section. The reduced vapor space creates a temperature gradient over the length of the furnace, and this gradient is variable and controllable depending upon the quantity of heat being transferred from the heat source to the heat sink.

Abstract: An alkali metal heat engine. A thermoelectric generator which circulates alkali metal through a cationic barrier to produce electricity. The device is capable of operating in a reduced gravity or gravity-free environment and without mechanical pumps because it collects and recirculates the liquid alkali metal with capillary wick structures. One capillary wick moves the alkali metal from the cooler side of the barrier to the hotter side, and another wick is used as a bypass structure to recirculate the undiffused alkali metal back to the heat source.

Abstract: A high efficiency evaporator is disclosed. The evaporator is made with a ous wick on the interior of the evaporator housing to facilitate movement of a refrigerant liquid within the housing. This aids in dispersing the refrigerant.

Abstract: An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

Abstract: A heat pipe with limited heat transfer capabilities in one direction. The heat pipe, which transfers heat in one direction in normal fashion, also transfers heat in the reverse direction, but only up to a prescribed point, beyond which the reverse heat flow cuts off. It operates because of the use of a limited liquid filling and at least one artery which is closed at the normal evaporator end and open ended at the normal condenser end.

Abstract: A heat pipe constructed to be bent to conform to a particular mechanical configuration after is is constructed. The wick in the evaporator region is constructed from sintered metal powder; while the wick in another region of the heat pipe is constructed with a screen wick to permit bending the pipe without destruction of the wick. Arteries wound from flexible screen material are continuous through both the sintered wick, into which they are inserted, and the screen wick, to which they are also attached.

Abstract: A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

Abstract: A mass produced, easily assembled heat exchanger for use in cooling a cabinet or other enclosure by convection over both ends of fins which penetrate the wall of the enclosure. The configuration of the preferred embodiment has offset fins alternating in and out of the enclosure with the overlap at the enclosure wall and each fin acting as a spacer for the adjacent ones. An alternate embodiment uses a "U" shaped spacer to wrap around the overlapping edge of each fin, thus increasing the air flow space between fins without increasing the thickness of fins.

Abstract: Method and apparatus for determining when the cast of a blast furnace is substantially completed in a blast furnace cast system wherein direct viewing of the taphole is obstructed during the cast. In a system wherein viewing of the taphole is obstructed by hood means covering the iron trough, substantial completion of the cast may be determined by sensing changes in ambient conditions, e.g., a change in temperature within the hood means, vibration of the hood, and/or a change in the color of the flame generated at the discharge end of a slag runner.

Abstract: A multiple section heat pipe with swivel junctions between the sections. The individual sections are independent individual heat pipes configured to interlock with each other at rotatable joints filled with high heat conductivity liquid. The clearance between the sections is maintained small to establish capillary forces that maintain the conductive liquid in place and also to minimize the temperature differential across the rotating joint. When used in conjunction with several right angle heat pipes, the combination furnishes multiple possibilities for end to end relationship of a heat pipe system.

Abstract: A self-pumping solar liquid heating system which includes two solar collectors, a high temperature collector for generating vapor which expands and pumps fluid through the system, and a separate collector for collection of heat of utilization. A heat pipe transfers the heat from the high temperature collector to a vapor generator pump which moves the liquid in series through the second collector, a heat load and a liquid reservoir. Mechanical temperature controls are used to regulate the temperature of the heat load so no electrical power is required for the system.

Abstract: A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.

Abstract: A closely coupled two phase heat exchanger. The heat is transferred between gas streams by multiple intermediate fluid paths. Each of the several intermediate fluid paths passes alternately between the hot and the cold gas stream many times during its travel from the pump. The heat exchanger is designed so that the intermediate fluid vaporizes in the hot and condenses in the cold section each time, thereby minimizing the quantity of liquid necessary to transfer the heat. The pumping action for the intermediate fluid exchanger is accomplished by either mechanical or vapor pumps. An added feature of the heat exchanger is automatic control of the minimum temperature to which the hot gas is cooled. This is accomplished by shutting off one of several intermediate fluid paths at the cool end of the gas being cooled. The shutoff is accomplished either on the basis of temperature of the cooled gas or on the formation of condensates at the cool end of the gas flow path.