This project investigates a concept for a continuous refrigerator for operation in zero-gravity while cooling sensors to a temperature down to 0.3 kelvin. no capability such as this currently exists. the concept assumes a superfluid helium dewar (1.5 kelvin) as the high-temperatureheat sink. a… More

This proposal is for the development of coated metal seal systems for use in superfluid helium. emphasis will be of seals having a low sealing force with long lifetime. valves and transfer line couplings using the seals will also be designed.

The design of a mechanical, automatic heat switch for use with a refrigerator is proposed. emphasis is placed on obtaining a high switch ratio for the system. the main effort will consist of a careful thermal design for limiting the thermal radiative transfer which would reduce the off state thermal… More

This project covers the development of an adiabatic demagnetization refrigerator for use in zero gravity and employs an innovative precooler and thermal switch. in addition, the project involves the design of a superconducting magnet system energized by a superconducting flux pump. the system… More

This project concerns the development of a cryocooler to operate at 0.1 k in zero gravity. the cryocooler will use the principle of dilution of helium-3 solution by pure superfluid helium-4 for the cooling effect. a conventional dilution refrigerator requires gravity for operation, so an innovative… More

This proposal covers the development of a multistage cryocooler using the mikulin pulse tube cycle. the effort is directed toward the design of a high reliability, long lifetime 20 k unit with a refrigeration power of 1 watt.

This proposal covers the development of a fast cooldown lindehampson cryocooler. both single stage units, reaching 80 kelvin, and multi-stage units, reaching approximately 4 kelvin are possible. the unit can be used with gas bottles for short term use. for long lifetime either a mechanical or… More

This proposal covers the development of a cryocooler with a refrigeration capacity of 0.75 watt at 20 kelvin. the cryogenic unit will have a volume of less than 16 cm3, and can provide cooling for 5 minutes after a cooldown period of less than 20 seconds. the cryocooler uses a new fabrication… More

A cryocooler capable of operating under extremely high acceleration levels is proposed. the cryocooler uses the linde-hampson cycle, and can reach approximately 80 kelvin. multi-stage units, to reach lower temperatures, are also possible.

This proposal covers the development of a 0.25 watt, 80 k mechanical cryocooler for use in sensor cooling in space. the cryocooler will use the mikulin pulse tube cycle that has no moving parts in the cold section of the cryocooler. the elimination of cold moving parts removes the main sources of… More

The development of a liquid helium temperature cryocooler isplanned. a regenerative cryocooler will provide a 20 k temperature sink of a joule-thomson (j-t) stage using helium. an innovative design for the j-t stage heat exchangers will allow the use of simple, hermetic compressors, which will make… More

The new high tc superconducting materials can be used to construct current leads for conventional superconducting magnets. this is a relatively simple system, that will not place large demands on the material or on the fabrication process. however, the use of superconducting leads can result in… More

There is an acute need for very high efficiency heat exchangers in cryogenic applications. the goal of phase i is a heat exchanger design with an effectiveness 0.99. the heat exchanger geometry is a perforated, parallelplate type. the design methodology entails explicit calculation of heat transfer… More

Continuous, full power operation of high output semiconductor devices is generally limited by the heat dissipation capability of the device package. existing cooling schemes require cooling pumps and secondary radiators, which limits the application of these devices to large vehicles. this proposal… More

Many materials, such as doped si and ge, require low operating temperatures for operation. elemental superconductors, such as nb, must be operated below their transition temperatures, which do not exceed 9 kelvin. the existing cryocooler cycles, even if they can reach these temperatures, are very… More

The basic theory of regenerative cryocoolers indicates that operation at helium temperatures is possible. however,poor regenerator performance has been a barrier to operation below roughly 10-12 kelvin. this proposal covers the development of high performance, helium temperature regenerators that… More

A new catalyst configuration is proposed for para-ortho conversion of hydrogen. this endothermic reaction can have a significant refrigeration effect and is very important for long term cryogenic storage of liquid hydrogenon-orbit. the proposed effort entails investigation of; suitable catalytic… More

This project is concerned with the development of a helium temperature (4 kelvin) cryocooler. this cryocooler can be used for continuous cooling of superconducting devices that require these temperatures. these include magnetic resonance imaging (mri) superconducting magnet systems and… More

A concept for passive removal of water from compressed air supply lines is proposed. relying on surface tension effects to remove the water, this concept is feasible from a practical standpoint because of an inventive manufacturing approach developed by alabama cryogenic engineering. the phase i… More

The ability to lift heat from a selected portion of the spacecraft is required in a number of thermal management tasks for spaced based sensor and weapon systems. the proposed effort will develop the theoretical and analytical framework to assess the utility and feasibility of a hot piston pulse… More

The regenerator is a key component of a regenerative cryocooler, and the performance of the refrigerator is almost entirely set by the performance of the regenerator. This proposal presents an innovative approach to the fabrication of regenerator structures using fine wires of a metal having high… More

The performance of pulse tube cryocoolers has developed rapidly since the introduction of the orifice by Mikullin in 1984. The proposed effort covers an additional innovation that has been shown to result in increased cryocooler performance. The replacement of the orifice by a room temperature… More

Advanced methods for the conversion of natural gas to liquid fuels are needed so that natural gas energy resources can be better utilized. in recent research breakthroughs, ceramic monoliths have been used in partial oxidation to catalyze very fas, high selectivity synthesis of higher hydrocarbons… More

Partial oxidation reactions are very important routes to chemical synthesis. a significant fraction of all catalytic processes are oxidation reactions and there is a pressing demand to improve yield and reduce waste byproducts in the synthesis of a wide variety of specialty chemicals. in recent… More

Hybrid rocket propulsion systems are attractive because they use a single fluid (LOX), and avoid the high injector part count of dual fluid propulsion systems. However, the hole drilling costs associated with fabricating the injectors can be large, and the small holes that are desirable to achieve… More

The proposed effort covers the engineering aspects of a magnetic field source to be used in a table-top demonstrator of magnetic refrigeration. A prototype magnetic field source, based on the Halbach or "magic-ring" concept, will be designed, constructed and tested in the Phase I effort. The… More

50437-98-I An Artifical Pinning Center Approach to the Manufacture of High Field NbTaTi Superconducting Wire--Alabama Cryogenic Engineering, Inc., P.O. Box 2470, Huntsville, AL 35804-2470; (205) 536-8629 Dr. John B. Hendricks, Principal Investigator Ms. Mary T. Hendricks, Business Official DOE… More

51087-98-I A 10 Kelvin Pulse Tube Cryocooler Concept--Alabama Cryogenic Engineering, Inc., P.O. Box 2470, Huntsville, AL 35804-2470; (205) 536-8629 Dr. John B. Hendricks, Principal Investigator Ms. Mary T. Hendricks, Business Official DOE Grant No. DE-FG02-98ER82522 Amount: $75,000 Sensitive… More

Precursor materials for superconductors such as Nb3Sn and Nb3Al include low melting point components. Therefore, conventional extrusion processes with large area reductions are not possible because adiabatic heating raises the temperature above the melting point. In certain circumstances,… More

60275 Preliminary designs for the next generation of high energy physics colliders will require much higher magnetic field levels for successful operation. Currently available superconducting materials are either unable to reach these levels (NbTi) or they are much too expensive (Nb3Sn, Nb3Al… More

60275 Preliminary designs for the next generation of high energy physics colliders will require much higher magnetic field levels for successful operation. Currently available superconducting materials are either unable to reach these levels (NbTi) or they are much too expensive (Nb3Sn, Nb3Al… More

65415 Currently available niobium-tin superconductors do not meet the requirements that have been identified for the Next Generation Hadron Collider. The cost is too high, and the properties must be improved. This project will develop new production technology for niobium-tin… More

72984S03-I Currently available methods impose limits on the processing of multi-filamentary, superconducting wires used in high energy physics experiments. These limits can be severe when one of the wire components has a mechanical strength substantially smaller than the other component(s), and… More

72984-Currently available methods impose limits on the processing of multi-filamentary, superconducting wires used in high energy physics experiments. These limits can be severe when one of the wire components has a mechanical strength substantially smaller than the other component(s), and can… More

72984-Currently available methods impose limits on the processing of multi-filamentary, superconducting wires used in high energy physics experiments. These limits can be severe when one of the wire components has a mechanical strength substantially smaller than the other component(s), and can… More

Niobium tin superconductors have had large improvements in current density over the past few years. However, the effective filament diameters of these conductors are too large, which can limit their application in areas such as High Energy Physics Colliders, Fusion Devices, and laboratory… More