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1

Survey of cryogenic semiconductor devices  

SciTech Connect

Improved reliability and electronic performance can be achieved in a system operated at cryogenic temperatures because of the reduction in mechanical insult and in disruptive effects of thermal energy on electronic devices. Continuing discoveries of new superconductors with ever increasing values of T{sub c} above that of liquid nitrogen temperature (LNT) have provided incentive for developing semiconductor electronic systems that may also operate in the superconductor`s liquid nitrogen bath. Because of the interest in high-temperature superconductor (HTS) devices, liquid nitrogen is the cryogen of choice and LNT is the temperature on which this review is focused. The purpose of this survey is to locate and assemble published information comparing the room temperature (298 K), performance of commercially available conventional and hybrid semiconductor device with their performance at LNT (77K), to help establish their candidacy as cryogenic electronic devices specifically for use at LNT. The approach to gathering information for this survey included the following activities. Periodicals and proceedings were searched for information on the behavior of semiconductor devices at LNT. Telephone calls were made to representatives of semiconductor industries, to semiconductor subcontractors, to university faculty members prominent for their research in the area of cryogenic semiconductors, and to representatives of the National Aeronautics and Space Administration (NASA) and NASA subcontractors. The sources and contacts are listed with their responses in the introduction, and a list of references appears at the end of the survey.

Talarico, L.J.; McKeever, J.W.

1996-04-01

2

Cryogenic vacuumm RF feedthrough device  

DOEpatents

A cryogenic vacuum rf feedthrough device comprising: 1) a probe for insertion into a particle beam; 2) a coaxial cable comprising an inner conductor and an outer conductor, a dielectric/insulating layer surrounding the inner conductor, the latter being connected to the probe for the transmission of higher mode rf energy from the probe; and 3) a high thermal conductivity stub attached to the coaxial dielectric about and in thermal contact with the inner conductor which high thermal conductivity stub transmits heat generated in the vicinity of the probe efficiently and radially from the area of the probe and inner conductor all while maintaining useful rf transmission line characteristics between the inner and outer coaxial conductors.

Wu, Genfa (Yorktown, VA); Phillips, Harry Lawrence (Hayes, VA)

2008-12-30

3

Versatile three-dimensional cryogenic micropositioning device  

NASA Astrophysics Data System (ADS)

A simple design for a mechanically driven three-dimensional cryogenic micropositioner is presented. The design is based on a parallelogram structure constructed from leaf springs and wires. Actuation is achieved by the elastic deformation of the parallelogram by screws. Positions within a volume of roughly (2 mm)3 are attainable. The precision and reproducibility of positioning are in the ?m-range. The deviations from linearity are smaller than 10% for the whole working range and the deviation from orthogonality is smaller than 3°. Calibration measurements performed on a Cu-mesh with a lattice constant of 60 ?m are presented. In an experiment investigating the ballistic transport of carriers in the semimetal Bi, two such devices are used. The first one is used as a scanning unit for an optical fiber and the second one is used as micropositioner for a Cu point contact.

Heil, J.; Böhm, A.; Primke, M.; Wyder, P.

1996-01-01

4

Cryogenic Propellant Management Device: Conceptual Design Study  

NASA Technical Reports Server (NTRS)

Concepts of Propellant Management Devices (PMDs) were designed for lunar descent stage reaction control system (RCS) and lunar ascent stage (main and RCS propulsion) missions using liquid oxygen (LO2) and liquid methane (LCH4). Study ground rules set a maximum of 19 days from launch to lunar touchdown, and an additional 210 days on the lunar surface before liftoff. Two PMDs were conceptually designed for each of the descent stage RCS propellant tanks, and two designs for each of the ascent stage main propellant tanks. One of the two PMD types is a traditional partial four-screen channel device. The other type is a novel, expanding volume device which uses a stretched, flexing screen. It was found that several unique design features simplified the PMD designs. These features are (1) high propellant tank operating pressures, (2) aluminum tanks for propellant storage, and (3) stringent insulation requirements. Consequently, it was possible to treat LO2 and LCH4 as if they were equivalent to Earth-storable propellants because they would remain substantially subcooled during the lunar mission. In fact, prelaunch procedures are simplified with cryogens, because any trapped vapor will condense once the propellant tanks are pressurized in space.

Wollen, Mark; Merino, Fred; Schuster, John; Newton, Christopher

2010-01-01

5

Development of cryotribological theories & application to cryogenic devices. Final report  

SciTech Connect

This is the final report of a research program on low-temperature friction and wear, primarily focused on development of cryotribological theories and application to cryogenic devices, particularly superconducting magnets.

Iwasa, Yukikazu

2001-03-12

6

Verilog-A Device Models for Cryogenic Temperature Operation of Bulk Silicon CMOS Devices  

NASA Technical Reports Server (NTRS)

Verilog-A based cryogenic bulk CMOS (complementary metal oxide semiconductor) compact models are built for state-of-the-art silicon CMOS processes. These models accurately predict device operation at cryogenic temperatures down to 4 K. The models are compatible with commercial circuit simulators. The models extend the standard BSIM4 [Berkeley Short-channel IGFET (insulated-gate field-effect transistor ) Model] type compact models by re-parameterizing existing equations, as well as adding new equations that capture the physics of device operation at cryogenic temperatures. These models will allow circuit designers to create optimized, reliable, and robust circuits operating at cryogenic temperatures.

Akturk, Akin; Potbhare, Siddharth; Goldsman, Neil; Holloway, Michael

2012-01-01

7

Method and apparatus of cryogenic cooling for high temperature superconductor devices  

DOEpatents

A method and apparatus for providing cryogenic cooling to HTS devices, in particular those that are used in high-voltage electric power applications. The method involves pressurizing liquid cryogen to above one atmospheric pressure to improve its dielectric strength, while sub-cooling the liquid cryogen to below its saturation temperature in order to improve the performance of the HTS components of the device. An apparatus utilizing such a cooling method consists of a vessel that contains a pressurized gaseous cryogen region and a sub-cooled liquid cryogen bath, a liquid cryogen heating coupled with a gaseous cryogen venting scheme to maintain the pressure of the cryogen to a value in a range that corresponds to optimum dielectric strength of the liquid cryogen, and a cooling system that maintains the liquid cryogen at a temperature below its boiling point to improve the performance of HTS materials used in the device.

Yuan, Xing; Mine, Susumu

2005-02-15

8

Charge dissipative dielectric for cryogenic devices  

NASA Technical Reports Server (NTRS)

A Superconducting Quantum Interference Device (SQUID) is disclosed comprising a pair of resistively shunted Josephson junctions connected in parallel within a superconducting loop and biased by an external direct current (dc) source. The SQUID comprises a semiconductor substrate and at least one superconducting layer. The metal layer(s) are separated by or covered with a semiconductor material layer having the properties of a conductor at room temperature and the properties of an insulator at operating temperatures (generally less than 100 Kelvins). The properties of the semiconductor material layer greatly reduces the risk of electrostatic discharge that can damage the device during normal handling of the device at room temperature, while still providing the insulating properties desired to allow normal functioning of the device at its operating temperature. A method of manufacturing the SQUID device is also disclosed.

Cantor, Robin Harold (Inventor); Hall, John Addison (Inventor)

2007-01-01

9

Screen Channel Liquid Acquisition Devices for Cryogenic Propellants  

NASA Technical Reports Server (NTRS)

This paper describes an on-going project to study the application screen channel liquid acquisition devices to cryogenic propellant systems. The literature of screen liquid acquisition devices is reviewed for prior cryogenic experience. Test programs and apparatus are presented to study these devices. Preliminary results are shown demonstrating bubble points for 200 x 1400 wires per inch and 325 x 2300 wires per inch Dutch twill screens. The 200 x 1400 screen has a bubble point of 15.8 inches of water in isopropyl alcohol and 6.6 inches of water in liquid nitrogen. The 325 x 2300 screen has a bubble point of 24.5 inches of water in isopropyl alcohol, 10.7 inches of water in liquid nitrogen, and 1.83 inches of water in liquid hydrogen. These values are found to be in good agreement with the results reported in the literature.

Chato, David J.; Kudlac, Maureen T.

2005-01-01

10

Inverted Outflow Ground Testing of Cryogenic Propellant Liquid Acquisition Devices  

NASA Technical Reports Server (NTRS)

NASA is currently developing propulsion system concepts for human exploration. These propulsion concepts will require the vapor free acquisition and delivery of the cryogenic propellants stored in the propulsion tanks during periods of microgravity to the exploration vehicles engines. Propellant management devices (PMDs), such as screen channel capillary liquid acquisition devices (LADs), vanes and sponges have been used for earth storable propellants in the Space Shuttle Orbiter and other spacecraft propulsion systems, but only very limited propellant management capability currently exists for cryogenic propellants. NASA is developing PMD technology as a part of their cryogenic fluid management (CFM) project. System concept studies have looked at the key factors that dictate the size and shape of PMD devices and established screen channel LADs as an important component of PMD design. Modeling validated by normal gravity experiments is examining the behavior of the flow in the LAD channel assemblies (as opposed to only prior testing of screen samples) at the flow rates representative of actual engine service (similar in size to current launch vehicle upper stage engines). Recently testing of rectangular LAD channels has included inverted outflow in liquid oxygen and liquid hydrogen. This paper will report the results of liquid oxygen testing compare and contrast them with the recently published hydrogen results; and identify the sensitivity these results to flow rate and tank internal pressure.

Chato, David J.; Hartwig, Jason W.; Rame, Enrique; McQuillen, John B.

2014-01-01

11

Inverted Outflow Ground Testing of Cryogenic Propellant Liquid Acquisition Devices  

NASA Technical Reports Server (NTRS)

NASA is currently developing propulsion system concepts for human exploration. These propulsion concepts will require the vapor free acquisition and delivery of the cryogenic propellants stored in the propulsion tanks during periods of microgravity to the exploration vehicles engines. Propellant management devices (PMD's), such as screen channel capillary liquid acquisition devices (LAD's), vanes and sponges have been used for earth storable propellants in the Space Shuttle Orbiter and other spacecraft propulsion systems, but only very limited propellant management capability currently exists for cryogenic propellants. NASA is developing PMD technology as a part of their cryogenic fluid management (CFM) project. System concept studies have looked at the key factors that dictate the size and shape of PMD devices and established screen channel LADs as an important component of PMD design. Modeling validated by normal gravity experiments is examining the behavior of the flow in the LAD channel assemblies (as opposed to only prior testing of screen samples) at the flow rates representative of actual engine service (similar in size to current launch vehicle upper stage engines). Recently testing of rectangular LAD channels has included inverted outflow in liquid oxygen and liquid hydrogen. This paper will report the results of liquid oxygen testing compare and contrast them with the recently published hydrogen results; and identify the sensitivity of these results to flow rate and tank internal pressure.

Chato, David J.; Hartwig, Jason W.; Rame, Enrique; McQuillen, John B.

2014-01-01

12

Improved cryogenic coring device for sampling wetland soils  

SciTech Connect

This paper is the third in a series on the design and construction (Knaus 1986) and improvements (Knaus and Cahoon 1990) of a cryogenic soil-coring device (cryocorer). Freezing wetland soils in place during sampling eliminates compaction, dewatering, and loss of flocculent material at the water-sediment interface. The cryocorer is suitable for sampling soils of emergent marsh and mangrove forests as well as shallow water bottoms, although it has been used primarily for the former. A small-diameter frozen soil core minimizes disruption of the surface, can be evaluated immediately for overall quality, and can be used to measure soil profiles and subsample for further analysis. The cryocorer continues to be used in studies of wetland accretion and soil bulk density throughout the US. Concomitant with the increased use of the device, improvements in cryocorer design and application have occurred. Reported here are improvements in design that have been made since 1992 with references to wetland research in which the cryocorer has been used extensively.

Cahoon, D.R.; Lynch, J.C. [National Biological Service, Lafayette, LA (United States); Knaus, R.M. [Louisiana State Univ., Baton Rouge, LA (United States)

1996-09-01

13

Cryotribology: Development of cryotribological theories and application to cryogenic devices  

SciTech Connect

High-performance superconducting solenoids are susceptible to premature quenches, or superconducting to normal state transitions, due to abrupt conductor movements within the winding. Abrupt motions involving 5{approximately}10{mu}m conductor displacements dissipate sufficient energy to trigger a quench. Sliding and mechanical behaviors of materials at cryogenic temperatures have been experimentally examined. After accounting for changes in the sliding materials' low-temperature strength properties, we have found that the adhesion theory of friction and wear remains applicable at cryogenic temperatures. The adhesion friction theory suggests two methods for controlling unsteady sliding motions. The first involves the selection of sliding materials whose friction coefficients increase with increasing sliding speed. A number of material pairs have been examined for positive friction-velocity characteristics. This materials-based approach to frictional stabilization does not seem a viable option at 4.2 K. The second altemative is to preprogram the force conditions within high-risk regions of the winding to regulate the occurrence of unsteady sliding motions. Structural models are proposed to account for unsteady conductor motions on a variety of dimensional scales. The models are used to design a small superconducting solenoid. Performance of this solenoid suggests that force-based motion control is a potentially viable design approach for achieving successful dry-wound magnets.

Iwasa, Y.; Michael, P. (Massachusetts Inst. of Tech., Cambridge, MA (United States)); Rabinowicz, E. (Massachusetts Inst. of Tech., Cambridge, MA (United States) Massachusetts Inst. of Tech., Cambridge, MA (United States). Francis Bitter National Magnet Lab.)

1992-09-15

14

Anti-contamination device for cryogenic soft X-ray diffraction microscopy  

DOE PAGESBeta

Cryogenic microscopy allows one to view frozen hydrated biological and soft matter specimens with good structural preservation and a high degree of stability against radiation damage. We describe a liquid nitrogen-cooled anti-contamination device for cryogenic X-ray diffraction microscopy. The anti-contaminator greatly reduces the buildup of ice layers on the specimen due to condensation of residual water vapor in the experimental vacuum chamber. We show by coherent X-ray diffraction measurements that this leads to fivefold reduction of background scattering, which is important for far-field X-ray diffraction microscopy of biological specimens.

Huang, Xiaojing; Miao, Huijie; Nelson, Johanna; Turner, Joshua; Steinbrener, Jan; Shapiro, David; Kirz, Janos; Jacobsen, Chris

2011-05-01

15

Ultra-Low Noise HEMT Device Models: Application of On-Wafer Cryogenic Noise Analysis and Improved Parameter Extraction Techniques  

NASA Technical Reports Server (NTRS)

Significant advances in the development of HEMT technology have resulted in high performance cryogenic low noise amplifiers whose noise temperatures are within an order of magnitude of the quantum noise limit. Key to the identification of optimum HEMT structures at cryogenic temperatures is the development of on-wafer noise and device parameter extraction techniques. Techniques and results are described.

Bautista, J. J.; Hamai, M.; Nishimoto, M.; Laskar, J.; Szydlik, P.; Lai, R.

1995-01-01

16

Spin-transfer switching of orthogonal spin-valve devices at cryogenic temperatures  

SciTech Connect

We present the quasi-static and dynamic switching characteristics of orthogonal spin-transfer devices incorporating an out-of-plane magnetized polarizing layer and an in-plane magnetized spin valve device at cryogenic temperatures. Switching at 12?K between parallel and anti-parallel spin-valve states is investigated for slowly varied current as well as for current pulses with durations as short as 200 ps. We demonstrate 100% switching probability with current pulses 0.6?ns in duration. We also present a switching probability diagram that summarizes device switching operation under a variety of pulse durations, amplitudes, and polarities.

Ye, L., E-mail: ly17@nyu.edu; Gopman, D. B.; Rehm, L.; Backes, D.; Wolf, G.; Kent, A. D. [Department of Physics, New York University, New York, New York 10003 (United States); Ohki, T. [Raytheon BBN Technologies, Cambridge, Massachusetts 02138 (United States); Kirichenko, A. F.; Vernik, I. V.; Mukhanov, O. A. [HYPRES, 175 Clearbrook Road, Elmsford, New York 10523 (United States)

2014-05-07

17

Proton irradiation of a swept charge device at cryogenic temperature and the subsequent annealing  

NASA Astrophysics Data System (ADS)

A number of studies have demonstrated that a room temperature proton irradiation may not be sufficient to provide an accurate estimation of the impact of the space radiation environment on detector performance. This is a result of the relationship between defect mobility and temperature, causing the performance to vary subject to the temperature history of the device from the point at which it was irradiated. Results measured using Charge Coupled Devices (CCD) irradiated at room temperature therefore tend to differ from those taken when the device was irradiated at a cryogenic temperature, more appropriate considering the operating conditions in space, impacting the prediction of in-flight performance. This paper describes the cryogenic irradiation, and subsequent annealing of an e2v technologies Swept Charge Device (SCD) CCD236 irradiated at ?35.4°C with a 10 MeV equivalent proton fluence of 5.0 × 108 protons · cm?2. The CCD236 is a large area (4.4 cm2) X-ray detector that will be flown on-board the Chandrayaan-2 and Hard X-ray Modulation Telescope spacecraft, in the Chandrayaan-2 Large Area Soft X-ray Spectrometer and the Soft X-ray Detector respectively. The SCD is readout continually in order to benefit from intrinsic dither mode clocking, leading to suppression of the surface component of the dark current and allowing the detector to be operated at warmer temperatures than a conventional CCD. The SCD is therefore an excellent choice to test and demonstrate the variation in the impact of irradiation at cryogenic temperatures in comparison to a more typical room temperature irradiation.

Gow, J. P. D.; Smith, P. H.; Pool, P.; Hall, D. J.; Holland, A. D.; Murray, N. J.

2015-01-01

18

Parametric analysis of the liquid hydrogen and nitrogen bubble point pressure for cryogenic liquid acquisition devices  

NASA Astrophysics Data System (ADS)

This paper presents the parametric investigation of the factors which govern screen channel liquid acquisition device bubble point pressure in a low pressure propellant tank. The five test parameters that were varied included the screen mesh, liquid cryogen, liquid temperature and pressure, and type of pressurant gas. Bubble point data was collected using three fine mesh 304 stainless steel screens in two different liquids (hydrogen and nitrogen), over a broad range of liquid temperatures and pressures in subcooled and saturated liquid states, using both a noncondensible (helium) and autogenous (hydrogen or nitrogen) gas pressurization scheme. Bubble point pressure scales linearly with surface tension, but does not scale inversely with the fineness of the mesh. Bubble point pressure increases proportional to the degree of subcooling. Higher bubble points are obtained using noncondensible pressurant gases over the condensable vapor. The bubble point model is refined using a temperature dependent pore diameter of the screen to account for screen shrinkage at reduced liquid temperatures and to account for relative differences in performance between the two pressurization schemes. The updated bubble point model can be used to accurately predict performance of LADs operating in future cryogenic propellant engines and cryogenic fuel depots.

Hartwig, Jason; Adin Mann, Jay; Darr, Samuel R.

2014-09-01

19

Cryogenic refrigeration requirements for superconducting insertion devices in a light source  

SciTech Connect

This report discusses cryogenic cooling superconducting insertion devices for modern light sources. The introductory part of the report discusses the difference between wiggler and undulators and how the bore temperature may affect the performance of the magnets. The steps one would take to reduce the gap between the cold magnet pole are discussed. One section of the report is devoted to showing how one would calculate the heat that enters the device. Source of heat include, heat entering through the vacuum chamber, heating due to stray electrons and synchrotron radiation, heating due to image current on the bore, heat flow by conduction and radiation, and heat transfer into the cryostat through the magnet leads. A section of the report is devoted to cooling options such as small cryo-cooler and larger conventional helium refrigerators. This section contains a discussion as to when it is appropriate to use small coolers that do not have J-T circuits. Candidate small cryo-coolers are discussed in this section of the report. Cooling circuits for cooling with a conventional refrigerator are also discussed. A section of the report is devoted to vibration isolation and how this may affect how the cooling is attached to the device. Vibration isolation using straps is compared to vibration isolation using helium heat pipes. The vibration isolation of a conventional refrigeration system is also discussed. Finally, the cool down of an insertion device is discussed. The device can either be cooled down using liquid cryogenic nitrogen and liquid helium or by using the cooler used to keep the devices cold over the long haul.

Green, Michael A.; Green, Michael A.; Green, Michael A.

2003-08-15

20

A Study on the Body Insulators for the Bushing for HTS Devices at Cryogenic Temperature  

NASA Astrophysics Data System (ADS)

A bushing for high temperature superconducting devices (HTS bushing) is important because of applying high voltage to the cable or the winding of the transformer. It is cooled with liquid nitrogen (LN2) and is insulated with various insulators. For the development of the HTS bushing, it is necessary to know the fundamental characteristics of various insulators at cryogenic temperature. The electrical characteristics of the breakdown were studied under AC and impulse voltages. Also, the mechanical characteristics such as tensile strength in air and LN2 were studied. It was confirmed that GFRP is excellent not only electrical characteristics but also mechanical characteristics in LN2.

Kim, W. J.; Shin, H. S.; Kim, S. H.

21

A low power cryogenic 512 × 512-pixel infrared readout integrated circuit with modified MOS device model  

NASA Astrophysics Data System (ADS)

A low power cryogenic readout integrated circuit (ROIC) for 512 × 512-pixel infrared focal plane array (IRFPA) image system, is presented. In order to improve the precision of the circuit simulation at cryogenic temperatures, a modified MOS device model is proposed. The model is based on BSIM3 model, and uses correction parameters to describe carrier freeze-out effect at low temperatures to improve the fitting accuracy for low temperature MOS device simulation. A capacitive trans-impedance amplifier (CTIA) with inherent correlated double sampling (CDS) configuration is employed to realize a high performance readout interfacing circuit in a pixel area of 30 × 30 ?m2. Optimized column readout timing and structure are applied to reduce the power consumption. The experimental chip fabricated by a standard 0.35 ?m 2P4M CMOS process shows more than 10 MHz readout rate with less than 70 mW power consumption under 3.3 V supply voltage at 77-150 K operated temperatures. And it occupies an area of 18 × 17 mm2.

Zhao, Hongliang; Liu, Xinghui; Xu, Chao

2013-11-01

22

A cryogen-free ultralow-field superconducting quantum interference device magnetic resonance imaging system.  

PubMed

Magnetic resonance imaging (MRI) at microtesla fields using superconducting quantum interference device (SQUID) detection has previously been demonstrated, and advantages have been noted. Although the ultralow-field SQUID MRI technique would not need the heavy superconducting magnet of conventional MRI systems, liquid helium required to cool the low-temperature detector still places a significant burden on its operation. We have built a prototype cryocooler-based SQUID MRI system that does not require a cryogen. The SQUID detector and the superconducting gradiometer were cooled down to 3.7 K and 4.3 K, respectively. We describe the prototype design, characterization, a phantom image, and areas of further improvements needed to bring the imaging performance to parity with conventional MRI systems. PMID:25273745

Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob

2014-09-01

23

A cryogen-free ultralow-field superconducting quantum interference device magnetic resonance imaging system  

SciTech Connect

Magnetic resonance imaging (MRI) at microtesla fields using superconducting quantum interference device (SQUID) detection has previously been demonstrated, and advantages have been noted. Although the ultralow-field SQUID MRI technique would not need the heavy superconducting magnet of conventional MRI systems, liquid helium required to cool the low-temperature detector still places a significant burden on its operation. We have built a prototype cryocooler-based SQUID MRI system that does not require a cryogen. The SQUID detector and the superconducting gradiometer were cooled down to 3.7 K and 4.3 K, respectively. We describe the prototype design, characterization, a phantom image, and areas of further improvements needed to bring the imaging performance to parity with conventional MRI systems.

Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob, E-mail: ihahn@caltech.edu [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

2014-09-15

24

Design and demonstrate the performance of cryogenic components representative of space vehicles: Start basket liquid acquisition device performance analysis  

NASA Technical Reports Server (NTRS)

The objective was to design, fabricate and test an integrated cryogenic test article incorporating both fluid and thermal propellant management subsystems. A 2.2 m (87 in) diameter aluminum test tank was outfitted with multilayer insulation, helium purge system, low-conductive tank supports, thermodynamic vent system, liquid acquisition device and immersed outflow pump. Tests and analysis performed on the start basket liquid acquisition device and studies of the liquid retention characteristics of fine mesh screens are discussed.

1987-01-01

25

NASA Flexible Screen Propellant Management Device (PMD) Demonstration With Cryogenic Liquid  

NASA Technical Reports Server (NTRS)

While evaluating various options for liquid methane and liquid oxygen propellant management for lunar missions, Innovative Engineering Solutions (IES) conceived the flexible screen device as a potential simple alternative to conventional propellant management devices (PMD). An apparatus was designed and fabricated to test flexible screen devices in liquid nitrogen. After resolution of a number of issues (discussed in detail in the paper), a fine mesh screen (325 by 2300 wires per inch) spring return assembly was successfully tested. No significant degradation in the screen bubble point was observed either due to the screen stretching process or due to cyclic fatigue during testing. An estimated 30 to 50 deflection cycles, and approximately 3 to 5 thermal cycles, were performed on the final screen specimen, prior to and between formally recorded testing. These cycles included some "abusive" pressure cycling, where gas or liquid was driven through the screen at rates that produced differential pressures across the screen of several times the bubble point pressure. No obvious performance degradation or other changes were observed over the duration of testing. In summary, it is felt by the author that these simple tests validated the feasibility of the flexible screen PMD concept for use with cryogenic propellants.

Wollen, Mark; Bakke, Victor; Baker, James

2012-01-01

26

Precision Control of Thermal Transport in Cryogenic Single-Crystal Silicon Devices  

NASA Technical Reports Server (NTRS)

We report on the diffusive-ballistic thermal conductance of multi-moded single-crystal silicon beams measured below 1 K. It is shown that the phonon mean-free-path is a strong function of the surface roughness characteristics of the beams. This effect is enhanced in diffuse beams with lengths much larger than, even when the surface is fairly smooth, 510 nm rms, and the peak thermal wavelength is 0.6 microns. Resonant phonon scattering has been observed in beams with a pitted surface morphology and characteristic pit depth of 30 nm. Hence, if the surface roughness is not adequately controlled, the thermal conductance can vary significantly for diffuse beams fabricated across a wafer. In contrast, when the beam length is of order, the conductance is dominated by ballistic transport and is effectively set by the beam cross-sectional area. We have demonstrated a uniformity of +/-8% in fractional deviation for ballistic beams, and this deviation is largely set by the thermal conductance of diffuse beams that support the micro-electro-mechanical device and electrical leads. In addition, we have found no evidence for excess specific heat in single-crystal silicon membranes. This allows for the precise control of the device heat capacity with normal metal films. We discuss the results in the context of the design and fabrication of large-format arrays of far-infrared and millimeter wavelength cryogenic detectors.

Rostem, K.; Chuss, D. T.; Colazo, F. A.; Crowe, E. J.; Denis, K. L.; Lourie, N. P.; Moseley, S. H.; Stevenson, T. R.; Wollack, E. J.

2014-01-01

27

Thermal Integration of a Liquid Acquisition Device into a Cryogenic Feed System  

NASA Technical Reports Server (NTRS)

Primary objectives of this effort were to define the following: (1) Approaches for quantification of the accumulation of thermal energy within a capillary screen liquid acquisition device (LAD) for a lunar lander upper stage during periods of up to 210 days on the lunar surface, (2) techniques for mitigating heat entrapment, and (3) perform initial testing, data evaluation. The technical effort was divided into the following categories: (1) Detailed thermal modeling of the LAD/feed system interactions using both COMSOL computational fluid device and standard codes, (2) FLOW-3D modeling of bulk liquid to provide interfacing conditions for the LAD thermal modeling, (3) condensation conditioning of capillary screens to stabilize surface tension retention capability, and (4) subscale testing of an integrated LAD/feed system. Substantial progress was achieved in the following technical areas: (1) Thermal modeling and experimental approaches for evaluating integrated cryogen LAD/feed systems, at both the system and component levels, (2) reduced gravity pressure control analyses, (3) analytical modeling and testing for capillary screen conditioning using condensation and wicking, and (4) development of rapid turnaround testing techniques for evaluating LAD/feed system thermal and fluid integration. A comprehensive effort, participants included a diverse cross section of representatives from academia, contractors, and multiple Marshall Space Flight Center organizations.

Hastings, L. J.; Bolshinskiy, L. G.; Schunk, R. G.; Martin, A. K.; Eskridge, R. H.; Frenkel, A.; Grayson, G.; Pendleton, M. L.

2011-01-01

28

Precision control of thermal transport in cryogenic single-crystal silicon devices  

NASA Astrophysics Data System (ADS)

We report on the diffusive-ballistic thermal conductance of multi-moded single-crystal silicon beams measured below 1 K. It is shown that the phonon mean-free-path ? is a strong function of the surface roughness characteristics of the beams. This effect is enhanced in diffuse beams with lengths much larger than ?, even when the surface is fairly smooth, 5-10 nm rms, and the peak thermal wavelength is 0.6 ?m. Resonant phonon scattering has been observed in beams with a pitted surface morphology and characteristic pit depth of 30 nm. Hence, if the surface roughness is not adequately controlled, the thermal conductance can vary significantly for diffuse beams fabricated across a wafer. In contrast, when the beam length is of order ?, the conductance is dominated by ballistic transport and is effectively set by the beam cross-sectional area. We have demonstrated a uniformity of ±8% in fractional deviation for ballistic beams, and this deviation is largely set by the thermal conductance of diffuse beams that support the micro-electro-mechanical device and electrical leads. In addition, we have found no evidence for excess specific heat in single-crystal silicon membranes. This allows for the precise control of the device heat capacity with normal metal films. We discuss the results in the context of the design and fabrication of large-format arrays of far-infrared and millimeter wavelength cryogenic detectors.

Rostem, K.; Chuss, D. T.; Colazo, F. A.; Crowe, E. J.; Denis, K. L.; Lourie, N. P.; Moseley, S. H.; Stevenson, T. R.; Wollack, E. J.

2014-03-01

29

Precision control of thermal transport in cryogenic single-crystal silicon devices  

SciTech Connect

We report on the diffusive-ballistic thermal conductance of multi-moded single-crystal silicon beams measured below 1?K. It is shown that the phonon mean-free-path ? is a strong function of the surface roughness characteristics of the beams. This effect is enhanced in diffuse beams with lengths much larger than ?, even when the surface is fairly smooth, 5–10?nm rms, and the peak thermal wavelength is 0.6??m. Resonant phonon scattering has been observed in beams with a pitted surface morphology and characteristic pit depth of 30?nm. Hence, if the surface roughness is not adequately controlled, the thermal conductance can vary significantly for diffuse beams fabricated across a wafer. In contrast, when the beam length is of order ?, the conductance is dominated by ballistic transport and is effectively set by the beam cross-sectional area. We have demonstrated a uniformity of ±8% in fractional deviation for ballistic beams, and this deviation is largely set by the thermal conductance of diffuse beams that support the micro-electro-mechanical device and electrical leads. In addition, we have found no evidence for excess specific heat in single-crystal silicon membranes. This allows for the precise control of the device heat capacity with normal metal films. We discuss the results in the context of the design and fabrication of large-format arrays of far-infrared and millimeter wavelength cryogenic detectors.

Rostem, K., E-mail: karwan.rostem@nasa.gov [Department of Physics and Astronomy, The Johns Hopkins University, 3400 N. Charles St., Baltimore, Maryland 21218 (United States); NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, Maryland 20771 (United States); Chuss, D. T.; Colazo, F. A.; Crowe, E. J.; Denis, K. L.; Lourie, N. P.; Moseley, S. H.; Stevenson, T. R.; Wollack, E. J. [NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, Maryland 20771 (United States)

2014-03-28

30

Exploring cryogenic focused ion beam milling as a Group III-V device fabrication tool  

NASA Astrophysics Data System (ADS)

In this paper, we compare the features observed on a Group III-V strained layer superlattice (SLS) materials system as a result of room temperature Ga+ focused ion beam (FIB) milling to the features observed as a result of cryogenic FIB (cryo-FIB) milling at -135 °C under the same beam conditions (30 kV:1 nA). The features on the cryo-FIB milled material were observed both when the material was still cold and after it returned to room temperature. Although cryo-FIB milling yielded patterned features that were initially cleaner than comparable features defined by FIB milling at room temperature, we found that both room temperature FIB milling and cryo-FIB milling with subsequent sample warm-up resulted in the formation of Group III enriched features. These findings suggest that the structural and chemical properties of features fabricated by cryo-FIB milling are temperature-dependent, which is an important consideration when it comes to device fabrication. These dependencies will need to be better understood and controlled if cryo-FIB milling is to have future applications in this area.

Dolph, Melissa Commisso; Santeufemio, Christopher

2014-06-01

31

Cryogenic on-chip multiplexer for the study of quantum transport in 256 split-gate devices  

SciTech Connect

We present a multiplexing scheme for the measurement of large numbers of mesoscopic devices in cryogenic systems. The multiplexer is used to contact an array of 256 split gates on a GaAs/AlGaAs heterostructure, in which each split gate can be measured individually. The low-temperature conductance of split-gate devices is governed by quantum mechanics, leading to the appearance of conductance plateaux at intervals of 2e{sup 2}/h. A fabrication-limited yield of 94% is achieved for the array, and a “quantum yield” is also defined, to account for disorder affecting the quantum behaviour of the devices. The quantum yield rose from 55% to 86% after illuminating the sample, explained by the corresponding increase in carrier density and mobility of the two-dimensional electron gas. The multiplexer is a scalable architecture, and can be extended to other forms of mesoscopic devices. It overcomes previous limits on the number of devices that can be fabricated on a single chip due to the number of electrical contacts available, without the need to alter existing experimental set ups.

Al-Taie, H., E-mail: ha322@cam.ac.uk; Kelly, M. J. [Centre for Advanced Photonics and Electronics, Electrical Engineering Division, Department of Engineering, 9 J. J. Thomson Avenue, University of Cambridge, Cambridge CB3 0FA (United Kingdom) [Centre for Advanced Photonics and Electronics, Electrical Engineering Division, Department of Engineering, 9 J. J. Thomson Avenue, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Cavendish Laboratory, Department of Physics, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Smith, L. W.; Xu, B.; Griffiths, J. P.; Beere, H. E.; Jones, G. A. C.; Ritchie, D. A.; Smith, C. G. [Cavendish Laboratory, Department of Physics, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom)] [Cavendish Laboratory, Department of Physics, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); See, P. [National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW (United Kingdom)] [National Physical Laboratory, Hampton Road, Teddington, Middlesex TW11 0LW (United Kingdom)

2013-06-17

32

MOSFET's for Cryogenic Amplifiers  

NASA Technical Reports Server (NTRS)

Study seeks ways to build transistors that function effectively at liquid-helium temperatures. Report discusses physics of metaloxide/semiconductor field-effect transistors (MOSFET's) and performances of these devices at cryogenic temperatures. MOSFET's useful in highly sensitive cryogenic preamplifiers for infrared astronomy.

Dehaye, R.; Ventrice, C. A.

1987-01-01

33

Control mechanism for attenuation of thermal energy pulses using cold circulators in the cryogenic distribution system of fusion devices in tokamak configuration  

NASA Astrophysics Data System (ADS)

Operation and control of superconducting (SC) magnets in the fusion devices having tokamak configuration opens up the domain of varying peak thermal energy environment as a function of time, commensurate with the plasma pulses. The varied thermal energy environment, thus propagated to upstream of the cooling system, is responsible for the system level instability of the overall cryogenic system. The cryogenic distribution system, the regime of first impact point, therefore, has to be tuned so as to stay at the nearly stable zone of operation. The configuration of the cryogenic distribution system, considered in the present study, involves a liquid helium (LHe) bath as a thermal buffer, LHe submerged heat exchangers and cold circulator apart from the valves for implementations of the precise controls. The cold circulator supplies the forced flow supercritical helium, used for the cooling of SC magnets. The transients of the thermal energy pulses can be attenuated in the cryogenic distribution system by various methodologies. One of the adopted methodologies in the present study is with the precise speed control of the cold circulators. The adopted methodology is applied to various configurations of arrangements of internal components in the distribution system for obtaining system responses with superior attenuation of energy pulses. The process simulation approach, assumptions, considered inputs and constraints, process modeling with different configuration as well as results to accomplish the control scheme for the attenuation of the thermal energy pulses are described.

Bhattacharya, R.; Sarkar, B.; Vaghela, H.; Shah, N.

2014-01-01

34

An RF Sensor for Gauging Screen-Channel Liquid Acquisition Devices for Cryogenic Propellants  

NASA Technical Reports Server (NTRS)

A key requirement of a low-gravity screen-channel liquid acquisition device (LAD) is the need to retain 100% liquid in the channel in response to propellant outflow and spacecraft maneuvers. The point at which a screen-channel LAD ingests vapor is known as breakdown, and can be measured several different ways such as: visual observation of bubbles in the LAD channel outflow; a sudden change in pressure drop between the propellant tank and LAD sump outlet; or, an indication by wet-dry sensors placed in the LAD channel or outflow stream. Here we describe a new type of sensor for gauging a screen-channel LAD, the Radio Frequency Mass Gauge (RFMG). The RFMG measures the natural electromagnetic modes of the screen-channel LAD, which is very similar to an RF waveguide, to determine the amount of propellant in the channel. By monitoring several of the RF modes, we show that the RFMG acts as a global sensor of the LAD channel propellant fill level, and enables detection of LAD breakdown even in the absence of outflow. This paper presents the theory behind the RFMG-LAD sensor, measurements and simulations of the RF modes of a LAD channel, and RFMG detection of LAD breakdown in a channel using a simulant fluid during inverted outflow and long-term stability tests.

Zimmerli, Gregory A.; Metzger, Scott; Asipauskas, Marius

2014-01-01

35

Capillary acquisition devices for high-performance vehicles: Executive summary. [evaluation of cryogenic propellant management techniques using the centaur launch vehicle  

NASA Technical Reports Server (NTRS)

Technology areas critical to the development of cryogenic capillary devices were studied. Passive cooling of capillary devices was investigated with an analytical and experimental study of wicking flow. Capillary device refilling with settled fluid was studied using an analytical and experimental program that resulted in successful correlation of a versatile computer program with test data. The program was used to predict Centaur D-1S LO2 and LH2 start basket refilling. Comparisons were made between the baseline Centaur D-1S propellant feed system and feed system alternatives including systems using capillary devices. The preferred concepts from the Centaur D-1S study were examined for APOTV and POTV vehicles for delivery and round trip transfer of payloads between LEO and GEO. Mission profiles were determined to provide propellant usage timelines and the payload partials were defined.

Blatt, M. H.; Bradshaw, R. D.; Risberg, J. A.

1980-01-01

36

Cooling of superconducting devices by liquid storage and refrigeration unit  

DOEpatents

A system is disclosed for cooling superconducting devices. The system includes a cryogen cooling system configured to be coupled to the superconducting device and to supply cryogen to the device. The system also includes a cryogen storage system configured to supply cryogen to the device. The system further includes flow control valving configured to selectively isolate the cryogen cooling system from the device, thereby directing a flow of cryogen to the device from the cryogen storage system.

Laskaris, Evangelos Trifon; Urbahn, John Arthur; Steinbach, Albert Eugene

2013-08-20

37

Optical Detection Of Cryogenic Leaks  

NASA Technical Reports Server (NTRS)

Conceptual system identifies leakage without requiring shutdown for testing. Proposed device detects and indicates leaks of cryogenic liquids automatically. Detector makes it unnecessary to shut equipment down so it can be checked for leakage by soap-bubble or helium-detection methods. Not necessary to mix special gases or other materials with cryogenic liquid flowing through equipment.

Wyett, Lynn M.

1988-01-01

38

Cryogenic exciter  

DOEpatents

The disclosed technology is a cryogenic static exciter. The cryogenic static exciter is connected to a synchronous electric machine that has a field winding. The synchronous electric machine is cooled via a refrigerator or cryogen like liquid nitrogen. The static exciter is in communication with the field winding and is operating at ambient temperature. The static exciter receives cooling from a refrigerator or cryogen source, which may also service the synchronous machine, to selected areas of the static exciter and the cooling selectively reduces the operating temperature of the selected areas of the static exciter.

Bray, James William (Niskayuna, NY); Garces, Luis Jose (Niskayuna, NY)

2012-03-13

39

Cryotribology: Development of cryotribological theories and application to cryogenic devices. Interim report, June 15, 1985--August 31, 1992  

SciTech Connect

High-performance superconducting solenoids are susceptible to premature quenches, or superconducting to normal state transitions, due to abrupt conductor movements within the winding. Abrupt motions involving 5{approximately}10{mu}m conductor displacements dissipate sufficient energy to trigger a quench. Sliding and mechanical behaviors of materials at cryogenic temperatures have been experimentally examined. After accounting for changes in the sliding materials` low-temperature strength properties, we have found that the adhesion theory of friction and wear remains applicable at cryogenic temperatures. The adhesion friction theory suggests two methods for controlling unsteady sliding motions. The first involves the selection of sliding materials whose friction coefficients increase with increasing sliding speed. A number of material pairs have been examined for positive friction-velocity characteristics. This materials-based approach to frictional stabilization does not seem a viable option at 4.2 K. The second altemative is to preprogram the force conditions within high-risk regions of the winding to regulate the occurrence of unsteady sliding motions. Structural models are proposed to account for unsteady conductor motions on a variety of dimensional scales. The models are used to design a small superconducting solenoid. Performance of this solenoid suggests that force-based motion control is a potentially viable design approach for achieving successful dry-wound magnets.

Iwasa, Y.; Michael, P. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Rabinowicz, E. [Massachusetts Inst. of Tech., Cambridge, MA (United States); [Massachusetts Inst. of Tech., Cambridge, MA (United States). Francis Bitter National Magnet Lab.

1992-09-15

40

CRYOGENICS ISSUES  

Microsoft Academic Search

was the first year the cryogenic system has been used during a complete physics run at the four interaction points. Cryogenics worked quite smoothly and we can concentrate our review mainly on two subjects : the treatment of the mechanical oscillations which have perturbed the RF operation, and a new topic which is the influence of the beam on the

Philippe Gayet; Serge Claudet; Dieter Kaiser; Gunter Winkler

41

Design and construction of a cryogenic distillation device for removal of krypton for liquid xenon dark matter detectors.  

PubMed

Liquid xenon (Xe) is one of the commendable detecting media for the dark matter detections. However, the small content of radioactive krypton-85 ((85)Kr) always exists in the commercial xenon products. An efficient cryogenic distillation system to remove this krypton (Kr) from commercial xenon products has been specifically designed, developed, and constructed in order to meet the requirements of the dark matter experiments with high- sensitivity and low-background. The content of krypton in regular commercial xenon products can be reduced from 10(-9) to 10(-12), with 99% xenon collection efficiency at maximum flow rate of 5 kg/h (15SLPM). The purified xenon gases produced by this distillation system can be used as the detecting media in the project of Panda X, which is the first dark matter detector developed in China. PMID:24517821

Wang, Zhou; Bao, Lei; Hao, Xihuan; Ju, Yonglin

2014-01-01

42

Cryogenic Production Testing  

NASA Astrophysics Data System (ADS)

Rockwell has realized rapid testing of Infrared Focal Plane Arrays (IRFPAs) using a totally automated cryogenic test station with the latest technology in device handling, data acquisition, illumination and throughput capabilities. This station provides testing of HgCdTe Focal Plane Arrays fabricated in a fully certified production facility. All aspects of this facility are under Quality Control surveillance including the hardware and software used by the automated test station.

Buchness, R. K.; Banks, E.; Doidge, J.; Gable, A.; Nelson, L.; Olsen, D.

1985-10-01

43

Cryogenic cooler for photoconductive cells  

SciTech Connect

Resolution and sensitivity of photoconducting light sensitive devices vary inversely with temperature. Hence it is desirable to provide cooling means for photoconductive radiation detectors. One type of low temperature photoconductor is fabricated by placing the photomultiplier tube in a double-walled vacuum Dewar flask. In another type, the detector is mounted near a cryogenic projection, or cold finger, emenating from a refrigerator. In this case fabrication is critical, and great care must be exercised when the cryogenic cold finger is inserted in the Dewar well in order to avoid breakage. A different solution herein to the problem provides detector not as prior devices to breakage of the Dewar detector wall.

Gaskin, V. R.; Horvath, E. P.; Jansson, R. M.

1985-02-26

44

Cryogenic refrigerator  

Microsoft Academic Search

This patent describes a modified Stirling cycle cryogenic refrigerator. It has a first piston for compressing a working gas in a first cylinder, a second piston for expanding such working gas in a second cylinder, channel means connecting the first and second cylinders, and a cold head in thermal contact with the working gas in the second cylinder. It comprises:

Malaker

1989-01-01

45

Acquisition and correlation of cryogenic nitrogen mass flow data through a multiple orifice Joule-Thomson device  

NASA Technical Reports Server (NTRS)

Liquid nitrogen mass flow rate, pressure drop, and temperature drop data were obtained for a series of multiple orifice Joule-Thomson devices, known as Visco Jets, over a wide range of flow resistance. The test rig used to acquire the data was designed to minimize heat transfer so that fluid expansion through the Visco Jets would be isenthalpic. The data include a range of fluid inlet pressures from 30 to 60 psia, fluid inlet temperatures from 118 to 164 R, outlet pressures from 2.8 to 55.8 psia, outlet temperatures from 117 to 162 R and flow rate from 0.04 to 4.0 lbm/hr of nitrogen. A flow rate equation supplied by the manufacturer was found to accurately predict single-phase (noncavitating) liquid nitrogen flow through the Visco Jets. For cavitating flow, the manufacturer's equation was found to be inaccurate. Greatly improved results were achieved with a modified version of the single-phase equation. The modification consists of a multiplication factor to the manufacturer's equation equal to one minus the downstream quality on an isenthalpic expansion of the fluid across the Visco Jet. For a range of flow resistances represented by Visco Jet Lohm ratings between 17,600 and 80,000, 100 percent of the single-phase data and 85 percent of the two-phase data fall within + or - 10 percent of predicted values.

Papell, S. Stephen; Saiyed, Naseem H.; Nyland, Ted W.

1990-01-01

46

Cryogenic Technology Development for Exploration Missions  

NASA Technical Reports Server (NTRS)

This paper reports the status and findings of different cryogenic technology research projects in support of the President s Vision for Space Exploration. The exploration systems architecture study is reviewed for cryogenic fluid management needs. It is shown that the exploration architecture is reliant on the cryogenic propellants of liquid hydrogen, liquid oxygen and liquid methane. Needs identified include: the key technologies of liquid acquisition devices, passive thermal and pressure control, low gravity mass gauging, prototype pressure vessel demonstration, active thermal control; as well as feed system testing, and Cryogenic Fluid Management integrated system demonstration. Then five NASA technology projects are reviewed to show how these needs are being addressed by technology research. Projects reviewed include: In-Space Cryogenic Propellant Depot; Experimentation for the Maturation of Deep Space Cryogenic Refueling Technology; Cryogenic Propellant Operations Demonstrator; Zero Boil-Off Technology Experiment; and Propulsion and Cryogenic Advanced Development. Advances are found in the areas of liquid acquisition of liquid oxygen, mass gauging of liquid oxygen via radio frequency techniques, computational modeling of thermal and pressure control, broad area cooling thermal control strategies, flight experiments for resolving low gravity issues of cryogenic fluid management. Promising results are also seen for Joule-Thomson pressure control devices in liquid oxygen and liquid methane and liquid acquisition of methane, although these findings are still preliminary.

Chato, David J.

2007-01-01

47

Cryogenic applications of MMTD technology  

NASA Astrophysics Data System (ADS)

The authors propose a concept of a two-phase heat transfer system for a cryogenic application that is potentially very simple and reliable, does not require complicated start-up procedures and will not suffer from instability problems during operation. The main problem of extending the range of capillary two-phase system to cryogenic temperatures is the start-up from the supercritical conditions of the working fluid. Different designs are addressing this problem differently. The Multi-Modular Thermal Device (MMTD) employs a capillary pump that is located in the coldest zone of the two-phase heat transfer system. The pump circulates the fluid through a cold plate where the heat from the payload is absorbed. The authors recently published the principles of operation; the device can help resolve the start-up problem and support the operation at cryogenic temperatures in a simple and reliable way. .

Nikitkin, Michael N.; Bienert, Walter B.

2002-01-01

48

Cryogenic Technology for Superconducting Accelerators  

NASA Astrophysics Data System (ADS)

Superconducting devices such as magnets and cavities are key components in the accelerator field for increasing the beam energy and intensity, and at the same time making the system compact and saving on power consumption in operation. An effective cryogenic system is required to cool and keep the superconducting devices in the superconducting state stably and economically. The helium refrigeration system for application to accelerators will be discussed in this review article. The concept of two cooling modes -- the liquefier and refrigerator modes -- will be discussed in detail because of its importance for realizing efficient cooling and stable operation of the system. As an example of the practical cryogenic system, the TRISTAN cryogenic system of KEK Laboratory will be treated in detail and the main components of the cryogenic system, including the high-performance multichannel transfer line and liquid nitrogen circulation system at 80K, will also be discussed. In addition, we will discuss the operation of the cryogenic system, including the quench control and safety of the system. The satellite refrigeration system will be discussed because of its potential for wide application in medium-size accelerators and in industry.

Hosoyama, Kenji

2012-01-01

49

MEGARA Cryogenic System  

NASA Astrophysics Data System (ADS)

MEGARA (Multi Espectrógrafo en GTC de Alta Resolución para Astronomía) is the new integral field unit (IFU) and multi-object spectrograph (MOS) instrument for the Gran Telescopio Canarias (GTC). The selected cryogenic device to harbor the CCD detector for the MEGARA spectrograph is a liquid nitrogen open-cycle cryostat. The LN2 open-cycle cryostat is a custom made product which has been designed by the INAOE astronomical instrumentation group. The proposed cryostat offers modular stages for easy assembly and testing whilst also allowing future modifications to accommodate the required CCDs, electronics and optics.

Ferrusca, D.; Castillo, E.; Velázquez de la Rosa, M.; García-Vargas, M. L.; Zamorano, J.; Gil de Paz, A.; Gallego, J.; Carrasco, E.; Vílchez, J. M.; Sánchez-Moreno, F. M.

2013-05-01

50

Cryogenic Flow Sensor  

NASA Technical Reports Server (NTRS)

An acousto-optic cryogenic flow sensor (CFS) determines mass flow of cryogens for spacecraft propellant management. The CFS operates unobtrusively in a high-pressure, high-flowrate cryogenic environment to provide measurements for fluid quality as well as mass flow rate. Experimental hardware uses an optical plane-of-light (POL) to detect the onset of two-phase flow, and the presence of particles in the flow of water. Acousto-optic devices are used in laser equipment for electronic control of the intensity and position of the laser beam. Acousto-optic interaction occurs in all optical media when an acoustic wave and a laser beam are present. When an acoustic wave is launched into the optical medium, it generates a refractive index wave that behaves like a sinusoidal grating. An incident laser beam passing through this grating will diffract the laser beam into several orders. Its angular position is linearly proportional to the acoustic frequency, so that the higher the frequency, the larger the diffracted angle. If the acoustic wave is traveling in a moving fluid, the fluid velocity will affect the frequency of the traveling wave, relative to a stationary sensor. This frequency shift changes the angle of diffraction, hence, fluid velocity can be determined from the diffraction angle. The CFS acoustic Bragg grating data test indicates that it is capable of accurately determining flow from 0 to 10 meters per second. The same sensor can be used in flow velocities exceeding 100 m/s. The POL module has successfully determined the onset of two-phase flow, and can distinguish vapor bubbles from debris.

Justak, John

2010-01-01

51

Cryogenic High-Sensitivity Magnetometer  

NASA Technical Reports Server (NTRS)

A proposed magnetometer for use in a cryogenic environment would be sensitive enough to measure a magnetic-flux density as small as a picogauss (10(exp -16) Tesla). In contrast, a typical conventional flux-gate magnetometer cannot measure a magnetic-flux density smaller that about 1 microgauss (10(exp -10) Tesla). One version of this device, for operation near the low end of the cryogenic temperature range, would include a piece of a paramagnetic material on a platform, the temperature of which would be controlled with a periodic variation. The variation in temperature would be measured by use of a conventional germanium resistance thermometer. A superconducting coil would be wound around the paramagnetic material and coupled to a superconducting quantum interference device (SQUID) magnetometer.

Day, Peter; Chui, Talso; Goodstein, David

2005-01-01

52

Cryogenic fluid management experiment  

NASA Technical Reports Server (NTRS)

The cryogenic fluid management experiment (CFME), designed to characterize subcritical liquid hydrogen storage and expulsion in the low-q space environment, is discussed. The experiment utilizes a fine mesh screen fluid management device to accomplish gas-free liquid expulsion and a thermodynamic vent system to intercept heat leak and control tank pressure. The experiment design evolved from a single flight prototype to provision for a multimission (up to 7) capability. A detailed design of the CFME, a dynamic test article, and dedicated ground support equipment were generated. All materials and parts were identified, and components were selected and specifications prepared. Long lead titanium pressurant spheres and the flight tape recorder and ground reproduce unit were procured. Experiment integration with the shuttle orbiter, Spacelab, and KSC ground operations was coordinated with the appropriate NASA centers, and experiment interfaces were defined. Phase 1 ground and flight safety reviews were conducted. Costs were estimated for fabrication and assembly of the CFME, which will become the storage and supply tank for a cryogenic fluid management facility to investigate fluid management in space.

Eberhardt, R. N.; Bailey, W. J.; Fester, D. A.

1981-01-01

53

Refrigeration for Cryogenic Sensors  

NASA Technical Reports Server (NTRS)

Research in cryogenically cooled refrigerators is discussed. Low-power Stirling cryocoolers; spacecraft-borne long-life units; heat exchangers; performance tests; split-stirling, linear-resonant, cryogenic refrigerators; and computer models are among the topics discussed.

Gasser, M. G. (editor)

1983-01-01

54

Cryogenic immersion microscope  

DOEpatents

A cryogenic immersion microscope whose objective lens is at least partially in contact with a liquid reservoir of a cryogenic liquid, in which reservoir a sample of interest is immersed is disclosed. When the cryogenic liquid has an index of refraction that reduces refraction at interfaces between the lens and the sample, overall resolution and image quality are improved. A combination of an immersion microscope and x-ray microscope, suitable for imaging at cryogenic temperatures is also disclosed.

Le Gros, Mark (Berkeley, CA); Larabell, Carolyn A. (Berkeley, CA)

2010-12-14

55

Cryogenic Fluid Management Facility  

Microsoft Academic Search

The Cryogenic Fluid Management Facility is a reusable test bed which is designed to be carried within the Shuttle cargo bay to investigate the systems and technologies associated with the efficient management of cryogens in space. Cryogenic fluid management consists of the systems and technologies for: (1) liquid storage and supply, including capillary acquisition\\/expulsion systems which provide single-phase liquid to

R. N. Eberhardt; W. J. Bailey

1985-01-01

56

Recent Developments and Qualification of Cryogenic Helium Flow Meters  

Microsoft Academic Search

Flow measurement of cryogenic fluids is a useful diagnostic tool not only to assess thermal performance of superconducting devices and related components but also for early diagnosis of faulty components\\/systems and to assure the correct sharing of cryogenic power. It is mainly performed on the recovery at room temperature of vapor from liquid boil-off due to lack of commercially available

Alain-Arthur Bézaguet; A Rivetti; L Serio

2002-01-01

57

Gamma Radiation Induced Calibration Shift for Four Cryogenic Thermometer Types  

Microsoft Academic Search

Cryogenic temperature sensors utilized in space environments are exposed to ionizing radiation with the total dose dependent upon the length of the mission. Based upon their minimal size and robust packaging, four models of cryogenic Resistance Thermometer Devices (RTDs) manufactured by Lake Shore Cryotronics, Inc. were tested to determine their reliability for space applications with regard to radiation. Samples of

S. Scott Courts; C. J. Yeager

2004-01-01

58

AFRL cryogenic technology development programs  

Microsoft Academic Search

This is an overview of the cryogenic refrigerator and cryogenic integration programs in development and characterization under the Cryogenic Technologies Group, Space Vehicles Directorate of the Air Force Research Laboratory (AFRL). The vision statement for the Air Force Research Laboratory Cryogenic Technologies Group is to support the space community as the center of excellence for developing and transitioning space cryogenic

T. M. Davis; B. J. Tomlinson

2008-01-01

59

Germanium JFET for Cryogenic Readout Electronics  

NASA Technical Reports Server (NTRS)

The n-channel Germanium junction field effect transistor (Ge-JFET) was designed and fabricated for cryogenic applications. The Ge-JFET exhibits superior noise performance at liquid nitrogen temperature (77 K). From the device current voltage characteristics of n-channel JFETs, it is seen that transconductance increases monotonically with the lowering of temperature to 4.2 K (liquid helium temperature).

Das, N. C.; Monroy, C.; Jhabvala, M.; Shu, P.

1999-01-01

60

NASA's Cryogenic Fluid Management Technology Project  

NASA Technical Reports Server (NTRS)

The Cryogenic Fluid Management (CFM) Project's primary objective is to develop storage, transfer, and handling technologies for cryogens that will support the enabling of high performance cryogenic propulsion systems, lunar surface systems and economical ground operations. Such technologies can significantly reduce propellant launch mass and required on-orbit margins, reduce or even eliminate propellant tank fluid boil-off losses for long term missions, and simplify vehicle operations. This paper will present the status of the specific technologies that the CFM Project is developing. The two main areas of concentration are analysis models development and CFM hardware development. The project develops analysis tools and models based on thermodynamics, hydrodynamics, and existing flight/test data. These tools assist in the development of pressure/thermal control devices (such as the Thermodynamic Vent System (TVS), and Multi-layer insulation); with the ultimate goal being to develop a mature set of tools and models that can characterize the performance of the pressure/thermal control devices incorporated in the design of an entire CFM system with minimal cryogen loss. The project does hardware development and testing to verify our understanding of the physical principles involved, and to validate the performance of CFM components, subsystems and systems. This database provides information to anchor our analytical models. This paper describes some of the current activities of the NASA's Cryogenic Fluid Management Project.

Tramel, Terri L.; Motil, Susan M.

2008-01-01

61

Fundamentals of Cryogenics  

NASA Technical Reports Server (NTRS)

Analysis of the extreme conditions that are encountered in cryogenic systems requires the most effort out of analysts and engineers. Due to the costs and complexity associated with the extremely cold temperatures involved, testing is sometimes minimized and extra analysis is often relied upon. This short course is designed as an introduction to cryogenic engineering and analysis, and it is intended to introduce the basic concepts related to cryogenic analysis and testing as well as help the analyst understand the impacts of various requests on a test facility. Discussion will revolve around operational functions often found in cryogenic systems, hardware for both tests and facilities, and what design or modelling tools are available for performing the analysis. Emphasis will be placed on what scenarios to use what hardware or the analysis tools to get the desired results. The class will provide a review of first principles, engineering practices, and those relations directly applicable to this subject including such topics as cryogenic fluids, thermodynamics and heat transfer, material properties at low temperature, insulation, cryogenic equipment, instrumentation, refrigeration, testing of cryogenic systems, cryogenics safety and typical thermal and fluid analysis used by the engineer. The class will provide references for further learning on various topics in cryogenics for those who want to dive deeper into the subject or have encountered specific problems.

Johnson, Wesley; Tomsik, Thomas; Moder, Jeff

2014-01-01

62

Cryogenic Material Properties Database Cryogenic Material Properties Database Cryogenic Material Properties Database Cryogenic Material Properties Database  

Microsoft Academic Search

NIST has published at least two references compiling cryogenic material properties. These include the Handbook on Materials for Superconducting Machinery and the LNG Materials & Fluids. Neither has been updated since 1977 and are currently out of print. While there is a great deal of published data on cryogenic material properties, it is often difficult to find and not in

E. D. Marquardt; Ray Radebaugh

63

ITER cryogenic system  

Microsoft Academic Search

The main ITER cryogenic users are the superconducting magnets together with the 80K thermal shields. The key requirements that drive the design of the ITER cryogenic system are the intrinsically pulsed heat deposition in the magnets due to electromagnetic field and nuclear heating cyclic variations, and the usage of large flow capacity helium circulating pumps for forced-flow cooling of the

V. Kalinin; E. Tada; F. Millet; N. Shatil

2006-01-01

64

Passive Cryogenic Sampler  

NASA Astrophysics Data System (ADS)

Sampling is the key step in any analysis regime. Gaseous systems only magnify the critical nature of the sampling step. The Passive Cryogenic Gas Sampler provides a proven, cost-effective way to obtain high-quality samples. This report specifies some advantages and design specifications of the Passive Cryogenic Gas Sampler.

65

Cryogenic Quenching Process for Electronic Part Screening  

NASA Technical Reports Server (NTRS)

The use of electronic parts at cryogenic temperatures (less than 100 C) for extreme environments is not well controlled or developed from a product quality and reliability point of view. This is in contrast to the very rigorous and well-documented procedures to qualify electronic parts for mission use in the 55 to 125 C temperature range. A similarly rigorous methodology for screening and evaluating electronic parts needs to be developed so that mission planners can expect the same level of high reliability performance for parts operated at cryogenic temperatures. A formal methodology for screening and qualifying electronic parts at cryogenic temperatures has been proposed. The methodology focuses on the base physics of failure of the devices at cryogenic temperatures. All electronic part reliability is based on the bathtub curve, high amounts of initial failures (infant mortals), a long period of normal use (random failures), and then an increasing number of failures (end of life). Unique to this is the development of custom screening procedures to eliminate early failures at cold temperatures. The ability to screen out defects will specifically impact reliability at cold temperatures. Cryogenic reliability is limited by electron trap creation in the oxide and defect sites at conductor interfaces. Non-uniform conduction processes due to process marginalities will be magnified at cryogenic temperatures. Carrier mobilities change by orders of magnitude at cryogenic temperatures, significantly enhancing the effects of electric field. Marginal contacts, impurities in oxides, and defects in conductor/conductor interfaces can all be magnified at low temperatures. The novelty is the use of an ultra-low temperature, short-duration quenching process for defect screening. The quenching process is designed to identify those defects that will precisely (and negatively) affect long-term, cryogenic part operation. This quenching process occurs at a temperature that is at least 25 C colder than the coldest expected operating temperature. This quenching process is the opposite of the standard burn-in procedure. Normal burn-in raises the temperature (and voltage) to activate quickly any possible manufacturing defects remaining in the device that were not already rejected at a functional test step. The proposed inverse burn-in or quenching process is custom-tailored to the electronic device being used. The doping profiles, materials, minimum dimensions, interfaces, and thermal expansion coefficients are all taken into account in determining the ramp rate, dwell time, and temperature.

Sheldon, Douglas J.; Cressler, John

2011-01-01

66

Cryogenic cooling for spacecraft sensors, instruments, and experiments  

NASA Technical Reports Server (NTRS)

Several disciplines requiring in-space cryogenic cooling are identified including high-energy, gamma-ray, and IR astronomy, relativity missions, and superconducting devices. Radiant coolers are limited in terms of temperature ranges and cooling loads. Other spacecraft cryogenic systems include stored solid cryogenic coolers using materials such as hydrogen, neon, argon, and methane. Two such cooler designs are described including one for the Nimbus F limb radiance inversion radiometer and one for the Nimbus G limb infrared monitoring of the atmosphere. Suggestions for increasing the performance of solid cryogenic coolers are made, such as a multimission cooler, a mechanical refrigerator, Stirling-cycle refrigerators, and Vuilleumier mechanized coolers. Techniques for obtaining cryogenic cooling in the milli-K range are identified as dilution refrigeration and adiabatic demagnetization.

Sherman, A.

1978-01-01

67

Development and testing of an advanced cryogenic thermal switch and cryogenic thermal switch test bed  

NASA Astrophysics Data System (ADS)

This paper describes development details and performance results of a high performance, highly reliable cryogenic thermal switch (CTSW), US Patent Number 6,276,144 B1, and cryogenic thermal switch test bed. The principle application for this device is to couple redundant cryocoolers to a cryogenic component with minimal parasitic heat leak from the non-operating cryocooler. Additional applications for the CTSW are also considered. Constructed of only three parts and weighing less than 80 g, the device operates based on differential thermal expansion. The design is readily scalable and operates with a variety of material selections. The device has demonstrated an "On" conductance greater than 3.5 W/K, an "Off" resistance of greater than 2300 K/W and a switching ratio of more than 5000, with no performance degradation due to thermal cycling. A cryogenic thermal switch test bed has been designed to demonstrate the system benefits of the device for systems utilizing redundant cryocoolers. This test bed utilizes two CTSWs in conjunction with two tactical cryocoolers to quantitatively measure the power savings and/or the operating temperature benefits of the CTSW. Additionally, the test bed may be used to life test and thermally cycle the CTSW.

Marland, B.; Bugby, D.; Stouffer, C.

2004-06-01

68

SNS Cryogenic Systems Commissioning  

SciTech Connect

The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.

Hatfield, D.; Casagrande, F.; Campisi, I.; Gurd, P.; Howell, M.; Stout, D.; Strong, H. [SNS Project, Oak Ridge National Laboratory, Tennessee, 37831 (United States); Arenius, D.; Creel, J.; Dixon, K.; Ganni, V.; Knudsen, P. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, Virginia, 23606 (United States)

2006-04-27

69

SNS Cryogenic Systems Commissioning  

NASA Astrophysics Data System (ADS)

The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K cold box (consisting of 4 stages of cold compressors), gaseous helium storage, helium purification and gas impurity monitoring system, liquid nitrogen storage and the cryogenic distribution transfer line system. The overall system commissioning and future plans will be presented.

Hatfield, D.; Casagrande, F.; Campisi, I.; Gurd, P.; Howell, M.; Stout, D.; Strong, H.; Arenius, D.; Creel, J.; Dixon, K.; Ganni, V.; Knudsen, P.

2006-04-01

70

Cryogenic test technology, 1984  

NASA Astrophysics Data System (ADS)

This report reviews the new information available on cryogenic test technology since the report of the Converters' Group on Cryogenic Test Technology was written in 1981. The present position is summarized. The major events since the Converters' report have been the completion and commissioning of the National Transonic Facility (NTF), the suspension of further work on the Douglas 4-WT blowdown tunnel, the conversion of ONERA T2 for cryogenic operation, the steady progress with the DF-LP KKK, and the slow but positive progress with the ETW project, including installation of the pilot tunnel PETW.

North, R. J.; Schimanski, D.; Hartzuiker, J. P.

1985-04-01

71

Cryogenics on a Chip  

NASA Astrophysics Data System (ADS)

Low-temperature techniques often bring to mind cryogenic liquids, gas compressors, and massive installations. But researchers are now building refrigerators and sensors that work by controlling electrons on a silicon chip.

Pekola, Jukka; Schoelkopf, Robert; Ullom, Joel

2004-05-01

72

Liquid cryogenic lubricant  

NASA Technical Reports Server (NTRS)

Fluorinated polyethers are suitable lubricants for rolling-element bearings in cryogenic systems. Lubrication effectiveness is comparable to that of super-refined mineral oil lubricants operating at room temperature.

Dietrich, M. W.; Townsend, D. P.; Zaretsky, E. V.

1970-01-01

73

Cryogenic gel flow viscometer  

NASA Technical Reports Server (NTRS)

Coiled section of tubing measures viscous properties of gelled cryogenic propellants under conditions closely resembling flow in rocket engine systems. Characteristic flow curve provides data necessary for the design of prototype hardware systems using the liquid or gel of interest.

Globus, R. H.; Vanderwall, E. M.

1972-01-01

74

Cryogenically Cooled Field Effect Transistors for Low-Noise Systems  

NASA Technical Reports Server (NTRS)

Recent tends in the design, fabrication and use of High-Electron-Mobility-Transistors (HEMT) in low noise amplifiers are reviewed. Systems employing these devices have achieved the lowest system noise for wavelengths greater than three millimeters with relatively modest cryogenic cooling requirements in a variety of ground and space based applications. System requirements which arise in employing such devices in imaging applications are contrasted with other leading coherent detector candidates at microwave wavelengths. Fundamental and practical limitations which arise in the context of microwave application of field effect devices at cryogenic temperatures will be discussed from a component and systems point of view.

Wollack, Edward J.

2002-01-01

75

CRYOGENIC FACITLITY DESIGN IN BEPC II SUPERCONDUCTING UPGRADE.  

SciTech Connect

Three kinds of superconducting device are to be constructed at interaction regions in the upgrade of Beijing Electron-Positron Collider (BEPCII). Two sets of refrigerators with each capacity of 500W at 4.5K are adopted to provide the refrigeration for them. The cryogenic systems to support the operation of the superconducting facilities are under design by Harbin Institute of Technology in China. This paper presents the current design of main cryogenic facilities.

JIA,L.X.; WANG,L.; YANG,G.D.; ET AL.

2004-05-11

76

SNS Cryogenic Systems Commissioning  

Microsoft Academic Search

The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K

D. Hatfield; F. Casagrande; I. Campisi; P. Gurd; M. Howell; D. Stout; H. Strong; D. Arenius; J. Creel; K. Dixon; V. Ganni; P. Knudsen

2006-01-01

77

SNS Cryogenic Systems Commissioning  

Microsoft Academic Search

The Spallation Neutron Source (SNS) is under construction at Oak Ridge National Laboratory. The cold section of the Linac consists of 81 superconducting radio frequency cavities cooled to 2.1K by a 2400 watt cryogenic refrigeration system. The major cryogenic system components include warm helium compressors with associated oil removal and gas management, 4.5K cold box, 7000L liquid helium dewar, 2.1K

D. Hatfield; F. Casagrande; I. Campisi; P. Gurd; M. Howell; D. Stout; H. Strong; D. Arenius; J. Creel; K. Dixon; V. Ganni; P. Knudsen

2005-01-01

78

Highly resolved online organic-chemical speciation of evolved gases from thermal analysis devices by cryogenically modulated fast gas chromatography coupled to single photon ionization mass spectrometry.  

PubMed

Multi-dimensional analysis (MDA) in analytical chemistry is often applied to improve the selectivity of an analytical device and, therefore, to achieve a better overview of a sample composition. Recently, the hyphenation of thermogravimetry with single photo ionization mass spectrometry (TG-SPIMS) using an electron beam pumped excimer lamp (EBEL) for VUV radiation was applied. The concept of MDA has been realized by upgrading the TG-SPIMS system with a quasi comprehensive chromatographic separation step before the soft ionization (TG-GCxSPIMS). The system was characterized by the thermal analysis of diesel fuel, which has often been investigated by the GCxGC-community and is therefore a well-known sample material in MDA. Data from this measurement are used to explain the three-dimensional data structure and the advantages of the online TG-GCxSPIMS as compared to TG-SPIMS. Subsequently, the thermal decomposition behavior of a polymer, acrylonitrile-butadiene-styrene (ABS), is investigated. TG-GCxSPIMS provides a two-dimensional analysis of the evolved gaseous products. TG relevant data are obtained as well as an improved resolution power to separate isobaric molecular structures without losing any fraction of the samples, as is often the case in heart cutting approaches. Additionally, this solution is not associated with any extension of the measurement time. The assignment of the substance pattern to distinct species is improved as compared to solely using mass spectrometry without a preceding separation step. Furthermore, hitherto undetected compounds have been found in the evolved gases from the thermal degradation of ABS. Finally, a first estimation of the limit of detection has been carried out. This results in a significant decrease of the LOD in case of TG-GCxSPIMS (500 ppt for toluene) as compared to 30 ppb, which could be reached with TG-SPIMS. PMID:21043436

Saraji-Bozorgzad, Mohammad R; Eschner, Markus; Groeger, Thomas M; Streibel, Thorsten; Geissler, Robert; Kaisersberger, Erwin; Denner, Thomas; Zimmermann, Ralf

2010-12-01

79

Composite, vacuum-jacketed tubing replaces bellows in cryogenic systems  

NASA Technical Reports Server (NTRS)

For reliability control of high pressure cryogenic systems, one or more 90 degree elbow expansion devices are substituted for the metal bellows normally used. The device consists of a conducting tube inside a support tube, with the space between the tubes evacuated for insulation.

Calvert, H. F.

1964-01-01

80

Spacecraft cryogenic gas storage systems  

NASA Technical Reports Server (NTRS)

Cryogenic gas storage systems were developed for the liquid storage of oxygen, hydrogen, nitrogen, and helium. Cryogenic storage is attractive because of the high liquid density and low storage pressure of cryogens. This situation results in smaller container sizes, reduced container-strength levels, and lower tankage weights. The Gemini and Apollo spacecraft used cryogenic gas storage systems as standard spacecraft equipment. In addition to the Gemini and Apollo cryogenic gas storage systems, other systems were developed and tested in the course of advancing the state of the art. All of the cryogenic storage systems used, developed, and tested to date for manned-spacecraft applications are described.

Rysavy, G.

1971-01-01

81

Cryogenic Capillary Screen Heat Entrapment  

NASA Technical Reports Server (NTRS)

Cryogenic liquid acquisition devices (LADs) for space-based propulsion interface directly with the feed system, which can be a significant heat leak source. Further, the accumulation of thermal energy within LAD channels can lead to the loss of sub-cooled propellant conditions and result in feed system cavitation during propellant outflow. Therefore, the fundamental question addressed by this program was: "To what degree is natural convection in a cryogenic liquid constrained by the capillary screen meshes envisioned for LADs.?"Testing was first conducted with water as the test fluid, followed by LN2 tests. In either case, the basic experimental approach was to heat the bottom of a cylindrical column of test fluid to establish stratification patterns measured by temperature sensors located above and below a horizontal screen barrier position. Experimentation was performed without barriers, with screens, and with a solid barrier. The two screen meshes tested were those typically used by LAD designers, "200x1400" and "325x2300", both with Twill Dutch Weave. Upon consideration of both the water and LN2 data it was concluded that heat transfer across the screen meshes was dependent upon barrier thermal conductivity and that the capillary screen meshes were impervious to natural convection currents.

Bolshinskiy, L.G.; Hastings, L.J.; Stathman, G.

2007-01-01

82

Surface-confined molecular coolers for cryogenics.  

PubMed

An excellent molecule-based cryogenic magnetic refrigerant, gadolinium acetate tetrahydrate, is here used to decorate selected portions of silicon substrate. By quantitative magnetic force microscopy for a variable applied magnetic field near liquid-helium temperature, the molecules are demonstrated to hold their magnetic properties intact, and therefore their cooling functionality, after their deposition. These results represent a step forward towards the realization of a molecule-based micro-refrigerating device at very low temperatures. PMID:23401287

Lorusso, Giulia; Jenkins, Mark; González-Monje, Pablo; Arauzo, Ana; Sesé, Javier; Ruiz-Molina, Daniel; Roubeau, Olivier; Evangelisti, Marco

2013-06-01

83

Cryogenic Fluid Management Facility  

NASA Technical Reports Server (NTRS)

The Cryogenic Fluid Management Facility is a reusable test bed which is designed to be carried within the Shuttle cargo bay to investigate the systems and technologies associated with the efficient management of cryogens in space. Cryogenic fluid management consists of the systems and technologies for: (1) liquid storage and supply, including capillary acquisition/expulsion systems which provide single-phase liquid to the user system, (2) both passive and active thermal control systems, and (3) fluid transfer/resupply systems, including transfer lines and receiver tanks. The facility contains a storage and supply tank, a transfer line and a receiver tank, configured to provide low-g verification of fluid and thermal models of cryogenic storage and transfer processes. The facility will provide design data and criteria for future subcritical cryogenic storage and transfer system applications, such as Space Station life support, attitude control, power and fuel depot supply, resupply tankers, external tank (ET) propellant scavenging, and ground-based and space-based orbit transfer vehicles (OTV).

Eberhardt, R. N.; Bailey, W. J.

1985-01-01

84

Long hold time cryogens dewar  

SciTech Connect

This patent describes a dewar for maintaining superconducting temperatures for an extended period of time comprising an outer case, comprising cryogen containing chambers. The improved structure describes how the dewar is constructed so that each of the cryogen chambers completely surrounds the next innermost one of the cryogen chambers, and, except for the innermost of the cryogen chambers. The cryogens contained in each of the chambers are maintained in states such that each cryogen has a progressively higher phase change temperature proceeding from the innermost one of the cryogen chambers to the outermost one of the cryogen chambers and isothermal suspension means for suspending all of the cryogen chambers within the dewar wherein the outermost one of the cryogen chambers is suspended in the dewar solely by isothermal suspension means comprising rods having a low thermal conductivity and all of the cryogen chambers, except the outermost cryogen chamber, are suspended in the dewar solely by isothermal suspension means comprising cords having a low thermal conductivity.

Fixsen, D.J.; Hastings, R.N.; Imsdahl, J.A.

1989-01-10

85

OGMS of cryogenically enhanced magnetics  

Microsoft Academic Search

The magnetic susceptibility of paramagnetic particles is enhanced by cryogenic treatment. The subsequent increased response to a magnetic force density is exploited to enhance particle deflection in open gradient magnetic separation (OGMS). Both grade and recovery values are considerably increased by the cryogenic treatment of the feed material. The cryogenic method is most useful if the response of the magnetic

P. Krist; J. Boehm; R. Gerber; D. R. Kelland

1992-01-01

86

Cryogenic foil bearing turbopumps  

NASA Technical Reports Server (NTRS)

Cryogenic foil bearing turbopumps offer high reliability and low cost. The fundamental cryogenic foil bearing technology has been validated in both liquid hydrogen and liquid oxygen. High load capacity, excellent rotor dynamics, and negligible bearing wear after over 100 starts and stops, and over many hours of testing, were observed in both fluids. An experimental liquid hydrogen foil bearing turbopump was also successfully demonstrated. The results indicate excellent stability, high reliability, wide throttle-ability, low bearing cooling flow, and two-phase bearing operability. A liquid oxygen foil bearing turbopump has been built and is being tested at NASA MSFC.

Gu, Alston L.

1993-01-01

87

Cryogenic Propellant Densification Study  

NASA Technical Reports Server (NTRS)

Ground and vehicle system requirements are evaluated for the use of densified cryogenic propellants in advanced space transportation systems. Propellants studied were slush and triple point liquid hydrogen, triple point liquid oxygen, and slush and triple point liquid methane. Areas of study included propellant production, storage, transfer, vehicle loading and system requirements definition. A savings of approximately 8.2 x 100,000 Kg can be achieved in single stage to orbit gross liftoff weight for a payload of 29,484 Kg by utilizing densified cryogens in place of normal boiling point propellants.

Ewart, R. O.; Dergance, R. H.

1978-01-01

88

Cryogenic Transfer Line Chilldown  

NASA Technical Reports Server (NTRS)

The transient behavior of a small scale cryogenic transfer line was investigated during chilldown to cryogenic temperatures. The vacuum-jacketed apparatus consisted of a vertical tube followed by a near horizontal tube. The apparatus was equipped with view ports in the near horizontal section to allow visual observation of the flow patterns. Wall temperatures were measured at various locations along the length of the transfer line. Each test was conducted at a constant liquid volumetric flowrate at the transfer line inlet until saturation temperatures were obtained throughout the system.

VanDresar, Neil T.; Siegwarth, James D.

2003-01-01

89

Cryogenic Hybrid Magnetic Bearing  

NASA Technical Reports Server (NTRS)

Cryogenic hybrid magnetic bearing is example of class of magnetic bearings in which permanent magnets and electromagnets used to suspend shafts. Electromagnets provide active control of position of shaft. Bearing operates at temperatures from -320 degrees F (-196 degrees C) to 650 degrees F (343 degrees C); designed for possible use in rocket-engine turbopumps, where effects of cryogenic environment and fluid severely limit lubrication of conventional ball bearings. This and similar bearings also suitable for terrestrial rotating machinery; for example, gas-turbine engines, high-vacuum pumps, canned pumps, precise gimbals that suspend sensors, and pumps that handle corrosive or gritty fluids.

Meeks, Crawford R.; Dirusso, Eliseo; Brown, Gerald V.

1994-01-01

90

Cryogenic Model Materials  

NASA Technical Reports Server (NTRS)

An overview and status of current activities seeking alternatives to 200 grade 18Ni Steel CVM alloy for cryogenic wind tunnel models is presented. Specific improvements in material selection have been researched including availability, strength, fracture toughness and potential for use in transonic wind tunnel testing. Potential benefits from utilizing damage tolerant life-prediction methods, recently developed fatigue crack growth codes and upgraded NDE methods are also investigated. Two candidate alloys are identified and accepted for cryogenic/transonic wind tunnel models and hardware.

Kimmel, W. M.; Kuhn, N. S.; Berry, R. F.; Newman, J. A.

2001-01-01

91

QUANTUM ELECTRONIC DEVICES: Cryogenic Faraday isolator  

NASA Astrophysics Data System (ADS)

A Faraday isolator is described in which thermal effects are suppressed by cooling down to liquid nitrogen temperatures. The principal scheme, main characteristics and modifications of the isolator are presented. The isolation degree is studied experimentally for the subkilowatt average laser radiation power. It is shown that the isolator can be used at radiation powers up to tens of kilowatts.

Zheleznov, D. S.; Zelenogorskii, V. V.; Katin, E. V.; Mukhin, I. B.; Palashov, O. V.; Khazanov, Efim A.

2010-05-01

92

Temperature-sensed cryogenic bleed maintains liquid state in transfer line  

NASA Technical Reports Server (NTRS)

Inverted tee, installed at a high point in a cryogenic transfer line, is equipped with an insulated bleed line that passes a fixed amount of cryogenic fluid at atmospheric pressure. A sensing device activates a vent valve in the tee stack whenever gaseous nitrogen is present.

Lindgren, A. R.

1967-01-01

93

Cryogenics Research and Engineering Experience  

NASA Technical Reports Server (NTRS)

Energy efficient storage, transfer and use of cryogens and cryogenic propellants on Earth and in space have a direct impact on NASA, government and commercial programs. Research and development on thermal insulation, propellant servicing, cryogenic components, material properties and sensing technologies provides industry, government and research institutions with the cross-cutting technologies to manage low-temperature applications. Under the direction of the Cryogenic Testing Lab at Kennedy Space Center, the work experience acquired allowed me to perform research, testing, design and analysis of current and future cryogenic technologies to be applied in several projects.

Toro Medina, Jaime A.

2013-01-01

94

High Power Cryogenic Targets  

SciTech Connect

The development of high power cryogenic targets for use in parity violating electron scattering has been a crucial ingredient in the success of those experiments. As we chase the precision frontier, the demands and requirements for these targets have grown accordingly. We discuss the state of the art, and describe recent developments and strategies in the design of the next generation of these targets.

Gregory Smith

2011-08-01

95

Guidance Document Cryogenic Liquids  

E-print Network

have boiling points below -73°C (-100°F). The most common cryogenic liquids currently on campus conditions of temperature and pressure. But all have two very important properties in common. First, the liquids and their vapors are extremely cold. The risk of destructive freezing of tissues is always present

96

Cryogenic structural support  

DOEpatents

A tensile support member is provided for use in a cryogenic environment. The member is in the form of a link formed of an epoxy glass laminate with at least one ply of the laminate having its fibers aligned circumferentially about the link.

Niemann, Ralph C. (Downers Grove, IL); Mataya, Karl F. (Lemont, IL); Gonczy, John D. (Oak Lawn, IL)

1982-01-01

97

Cryogenic expander recovery process  

Microsoft Academic Search

A process is described for treating a gaseous hydrocarbon-containing feed stream such as natural gas or refinery gas to leave the ethane in the hydrocarbon gaseous stream and to separate and recover the Câ and heavier hydrocarbon components. Increased recovery is achieved with the expenditure of less power by expanding the hydrocarbon gaseous feed stream in a cryogenic expansion step

J. D. Hammond; E. H. Deng

1981-01-01

98

Design of the NIF Cryogenic Target System  

SciTech Connect

The United States Department of Energy has embarked on a campaign to conduct credible fusion ignition experiments on the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory in 2010. The target assembly specified for this campaign requires the formation of a deuterium/tritium (DT) fuel ice layer in a 2 mm diameter capsule at the center of a 9 mm long by 5 mm diameter cylinder, called a hohlraum. The ice layer must be formed and maintained at temperatures below 20 K. At laser shot time, the target is positioned at the center of the NIF target chamber, aligned to the laser beams and held stable to less than 7 {micro}m rms. We have completed the final design of the Cryogenic Target System and are integrating the devices necessary to create, characterize and position the cryogenic target for ignition experiments. These designs, with supporting analysis and prototype test results, will be presented.

Gibson, C; Baltz, J; Malsbury, T; Atkinson, D; Brugmann, V; Coffield, F; Edwards, O; Haid, B; Locke, S; Shiromizu, S; Skulina, K

2008-06-10

99

Flexible cryogenic conduit  

SciTech Connect

A flexible and relatively low cost cryogenic conduit is described. The flexible cryogenic conduit of the present invention comprises a first inner corrugated tube with single braided serving, a second outer corrugated tube with single braided serving concentric with the inner corrugated tube, and arranged outwardly about the periphery of the inner corrugated tube and between the inner and outer corrugated tubes: a superinsulation layer; a one half lap layer of polyester ribbon; a one half lap layer of copper ribbon; a spirally wound refrigeration tube; a second one half lap layer of copper ribbon; a second one half lap layer of polyester ribbon; a second superinsulation layer; a third one half lap layer of polyester ribbon; and a spirally wound stretchable and compressible filament.

Brindza, P.D.; Wines, R.R.; Takacs, J.J.

1999-12-21

100

Cryogenic Control System  

SciTech Connect

The control system (CS) for the cryogenic arrangement of the DO Liquid Argon Calorimeter consists of a Texas instruments 560/565 Programmable Logical Controller (PLC), two remote bases with Remote Base Controllers and a corresponding set of input/output (I/O) modules, and a PC AST Premium 286 (IBM AT Compatible). The PLC scans a set of inputs and provides a set of outputs based on a ladder logic program and PID control loops. The inputs are logic or analog (current, voltage) signals from equipment status switches or transducers. The outputs are logic or analog (current or voltage) signals for switching solenoids and positioning pneumatic actuators. Programming of the PLC is preformed by using the TISOFT2/560/565 package, which is installed in the PC. The PC communicates to the PLC through a serial RS232 port and provides operator interface to the cryogenic process using Xpresslink software.

Goloborod'ko, S.; /Fermilab

1989-02-27

101

Cryogenic support system  

DOEpatents

A support system is disclosed for restraining large masses at very low or cryogenic temperatures. The support system employs a tie bar that is pivotally connected at opposite ends to an anchoring support member and a sliding support member. The tie bar extends substantially parallel to the longitudinal axis of the cold mass assembly, and comprises a rod that lengthens when cooled and a pair of end attachments that contract when cooled. The rod and end attachments are sized so that when the tie bar is cooled to cryogenic temperature, the net change in tie bar length is approximately zero. Longitudinal force directed against the cold mass assembly is distributed by the tie bar between the anchoring support member and the sliding support member.

Nicol, Thomas H. (Aurora, IL); Niemann, Ralph C. (Downers Grove, IL); Gonczy, John D. (Oak Lawn, IL)

1988-01-01

102

Stirling cycle cryogenic cooler  

NASA Astrophysics Data System (ADS)

A long lifetime Stirling cycle cryogenic cooler particularly adapted for space applications is described. It consists of a compressor section centrally aligned end to end with an expansion section, and respectively includes a reciprocating compressor piston and displacer radially suspended in interconnecting cylindrical housings by active magnetic bearings and has adjacent reduced clearance regions so as to be in noncontacting relationship therewith and wherein one or more of these regions operate as clearance seals. The piston and displacer are reciprocated in their housings by linear drive motors to vary the volume of respectively adjacent compression and expansion spaces which contain a gaseous working fluid and a thermal regenerator to effect Stirling cycle cryogenic cooling.

Gasser, M. G.; Sherman, A.; Studer, P. A.; Daniels, A.; Goldowsky, M. P.

1983-06-01

103

Cryogenic support system  

DOEpatents

A support system is disclosed for restraining large masses at very low or cryogenic temperatures. The support system employs a tie bar that is pivotally connected at opposite ends to an anchoring support member and a sliding support member. The tie bar extends substantially parallel to the longitudinal axis of the cold mass assembly, and comprises a rod that lengthens when cooled and a pair of end attachments that contract when cooled. The rod and end attachments are sized so that when the tie bar is cooled to cryogenic temperature, the net change in tie bar length is approximately zero. Longitudinal force directed against the cold mass assembly is distributed by the tie bar between the anchoring support member and the sliding support member. 7 figs.

Nicol, T.H.; Niemann, R.C.; Gonczy, J.D.

1988-11-01

104

Cryogenic treatment of gas  

DOEpatents

Systems and methods of treating a gas stream are described. A method of treating a gas stream includes cryogenically separating a first gas stream to form a second gas stream and a third stream. The third stream is cryogenically contacted with a carbon dioxide stream to form a fourth and fifth stream. A majority of the second gas stream includes methane and/or molecular hydrogen. A majority of the third stream includes one or more carbon oxides, hydrocarbons having a carbon number of at least 2, one or more sulfur compounds, or mixtures thereof. A majority of the fourth stream includes one or more of the carbon oxides and hydrocarbons having a carbon number of at least 2. A majority of the fifth stream includes hydrocarbons having a carbon number of at least 3 and one or more of the sulfur compounds.

Bravo, Jose Luis (Houston, TX); Harvey, III, Albert Destrehan (Kingwood, TX); Vinegar, Harold J. (Bellaire, TX)

2012-04-03

105

Stirling cycle cryogenic cooler  

NASA Technical Reports Server (NTRS)

A long lifetime Stirling cycle cryogenic cooler particularly adapted for space applications is described. It consists of a compressor section centrally aligned end to end with an expansion section, and respectively includes a reciprocating compressor piston and displacer radially suspended in interconnecting cylindrical housings by active magnetic bearings and has adjacent reduced clearance regions so as to be in noncontacting relationship therewith and wherein one or more of these regions operate as clearance seals. The piston and displacer are reciprocated in their housings by linear drive motors to vary the volume of respectively adjacent compression and expansion spaces which contain a gaseous working fluid and a thermal regenerator to effect Stirling cycle cryogenic cooling.

Gasser, M. G.; Sherman, A.; Studer, P. A.; Daniels, A.; Goldowsky, M. P. (inventors)

1983-01-01

106

Cryogenic turbopump bearing materials  

NASA Technical Reports Server (NTRS)

Materials used for modern cryogenic turbopump bearings must withstand extreme conditions of loads and speeds under marginal lubrication. Naturally, these extreme conditions tend to limit the bearing life. It is possible to significantly improve the life of these bearings, however, by improving the fatigue and wear resistance of bearing alloys, and improving the strength, liquid oxygen compatibility and lubricating ability of the bearing cage materials. Improved cooling will also help to keep the bearing temperatures low and hence prolong the bearing life.

Bhat, Biliyar N.

1989-01-01

107

Cryogenic insulation system  

Microsoft Academic Search

McDonnell Douglas Corp.'s LNG-containment system uses an inexpensive support structure to protect the primary nickel steel membrane against rupture or failure due to thermal and mechanical strains caused by loading and unloading the cryogenic liquid. The system also incorporates a novel corner support system t o react against the tension and bending of the primary liner caused by thermal stresses.

McCown

1979-01-01

108

Improved cryogenic aluminum mirrors  

Microsoft Academic Search

Optical surface deformation of metal mirrors used at cryogenic temperatures is reduced through the use of a new process of plating amorphous aluminum on aluminum. The AlumiPlateTM process (produced by AlumiPlate, Inc. in Minneapolis, MN) plates a layer of 99.9+% high purity aluminum about 125 micrometers thick atop the substrate. Very good surface finishes are produced by direct diamond turning

Daniel Vukobratovich; Ken Don; Richard E. Sumner

1998-01-01

109

Thermoelectric Generators used as Cryogenic Heat Engines  

NASA Astrophysics Data System (ADS)

A future experiment is being planned at the University of North Texas to design, build, and test a cryogenic heat engine(C. A. Ordonez, Am. J. Phys. 64), 479 (1996). suitable as an electric-vehicle power system. The power system shall then be installed in a demonstration vehicle. This will be a next-generation vehicle following the current project described in the accompanying poster, ``Experimental Car Which Uses Liquid Nitrogen as Its Fuel" by M. E. Parker et al. The cryogenic heat engine electric vehicle power system will incorporate both a thermoelectric generator and an ambient-temperature turbine or pneumatic-motor/generator. The thermoelectric generator shall use liquid nitrogen (under pressure) as its cold reservoir. Energy is produced with the thermoelectric generator by using the liquid/gas phase change to absorb heat. At the present time a study is being carried out to determine the efficiency of thermoelectric devices which are used as cryogenic heat engines. Initial data is being taken using frozen H_2O and CO2 as cold reservoirs. The results of the study shall be presented.

Smith, D. E.; Ordonez, C. A.

1997-03-01

110

Expandable Purge Chambers Would Protect Cryogenic Fittings  

NASA Technical Reports Server (NTRS)

Expandable ice-prevention and cleanliness-preservation (EIP-CP) chambers have been proposed to prevent the accumulation of ice or airborne particles on quick-disconnect (QD) fittings, or on ducts or tubes that contain cryogenic fluids. In the original application for which the EIP-CP chambers were conceived, there is a requirement to be able to disconnect and reconnect the QD fittings in rapid succession. If ice were to form on the fittings by condensation and freezing of airborne water vapor on the cold fitting surfaces, the ice could interfere with proper mating of the fittings, making it necessary to wait an unacceptably long time for the ice to thaw before attempting reconnection. By keeping water vapor away from the cold fitting surfaces, the EIP-CP chambers would prevent accumulation of ice, preserving the ability to reconnect as soon as required. Basically, the role of an EIP-CP chamber would be to serve as an enclosure for a flow of dry nitrogen gas that would keep ambient air away from QD cryogenic fittings. An EIP-CP chamber would be an inflatable device made of a fabriclike material. The chamber would be attached to an umbilical plate holding a cryogenic QD fitting.

Townsend, Ivan I., III

2004-01-01

111

Polyamide 66 as a cryogenic dielectric  

NASA Astrophysics Data System (ADS)

Improvements in superconductor and cryogenic technologies enable novel power apparatus, e.g., cables, transformers, fault current limiters, generators, it etc., with better device characteristics than their conventional counterparts. In these applications electrical insulation materials play an important role in system weight, footprint (size), and voltage level. The trend in the electrical insulation material selection has been to adapt or to employ conventional insulation materials to these new systems. However, at low temperatures, thermal contraction and loss of mechanical strength in many materials make them unsuitable for superconducting power applications. In this paper, a widely used commercial material was characterized as a potential cryogenic dielectric. The material is used in "oven bags" which is a heat-resistant polyamide (nylon) used in cooking (produced by ; this value is approximately 46kVmm higher than PPLP™. Comparison of the mechanical properties of PA and PPLP™ indicates that PA66 has low storage and loss moduli than PPLP™. It is concluded that PA66 may be a good candidate for cryogenic applications. Finally, a summary of dielectric properties of some of the commercial tape insulation materials and various polymers is also provided.

Tuncer, Enis; Polizos, Georgios; Sauers, Isidor; Randy James, D.; Ellis, Alvin R.; Messman, Jamie M.; Aytu?, Tolga

2009-09-01

112

Picowatt infrared power measurement using an absolute cryogenic radiometer  

Microsoft Academic Search

We report on initial measurements of the low-temperature thermal properties of a device that is similar to the experimental apparatus used for absolute cryogenic radiometry (ACR) within the Low Background Infrared Radiometry (LBIR) facility at NIST. The device consists of a receiver cavity mechanically and thermally connected to a temperature-controlled stage through a thin-walled polyimide tube which serves as a

S. M. Carr; S. I. Woods; T. M. Jung; A.. C. Carter; R. U. Datla

2009-01-01

113

Tracer-encapsulated cryogenic pellet production for particle transport diagnostics  

Microsoft Academic Search

A device for producing a tracer-encapsulated cryogenic pellet is constructed for an accurate transport diagnostic system to measure particle transport both parallel and perpendicular to the magnetic-field lines in magnetic confinement devices. As for the typical configuration of the tracer-encapsulated pellet, it is proposed that a 50–250 ?m diam tracer made of a light atom such as lithium, carbon, etc.,

S. Sudo; H. Itoh; K. Khlopenkov

1997-01-01

114

Commissioning of the Cryogenics of the LHC Long Straight Sections  

E-print Network

The LHC is made of eight circular arcs interspaced with eight Long Straight Sections (LSS). Most powering interfaces to the LHC are located in these sections where the particle beams are focused and shaped for collision, cleaning and acceleration. The LSSs are constituted of several unique cryogenic devices and systems like electrical feed-boxes, standalone superconducting magnets, superconducting links, RF cavities and final focusing superconducting magnets. This paper presents the cryogenic commissioning and the main results obtained during the first operation of the LHC Long Straight Sections.

Perin, A; Claudet, S; Darve, C; Ferlin, G; Millet, F; Parente, C; Rabehl, R; Soubiran, M; van Weelderen, R; Wagner, U

2010-01-01

115

Commissioning of the cryogenics of the LHC long straight sections  

SciTech Connect

The LHC is made of eight circular arcs interspaced with eight Long Straight Sections (LSS). Most powering interfaces to the LHC are located in these sections where the particle beams are focused and shaped for collision, cleaning and acceleration. The LSSs are constituted of several unique cryogenic devices and systems like electrical feed-boxes, standalone superconducting magnets, superconducting links, RF cavities and final focusing superconducting magnets. This paper presents the cryogenic commissioning and the main results obtained during the first operation of the LHC Long Straight Sections.

Perin, A.; Casas-Cubillos, J.; Claudet, S.; /CERN; Darve, C.; /Fermilab; Ferlin, G.; Millet, F.; Parente, C.; /CERN; Rabehl, R.; /Fermilab; Soubiran, M.; van Weelderen, R.; Wagner, U.; /CERN

2010-01-01

116

Design Parameters for Cryogenic Thermosyphons  

NASA Astrophysics Data System (ADS)

Cryogenic thermosyphons are the thermal conductors of choice for a variety of applications such as conduction-cooled superconducting devices. They exhibit a small effective thermal resistance at small cross-sections. A careful design, however, is crucial to ensure sufficient heat transport for all possible heatloads. The aim of this work is to obtain experimental results on critical limitations and the effective thermal conductivity dependent on the length, the cross-sectional area, and the working liquid fill level of a thermosyphon for different heatloads. For the experiments, a modular thermosyphon was designed with 5 different adiabatic tubes of length [cm]/cross-sectional diameter [cm] 10/1, 10/2, 30/0.5, 30/1, 30/2, which can be mounted between condenser and evaporator. The thermosyphon was operated with different fill levels of either nitrogen or neon and different heatloads. The effective thermal conductivity between condenser and evaporator was determined, dependent on the design parameters mentioned above. Additionally, the useful temperature range of operation was determined, and limitations were monitored and visualized using a built-in camera. The results can support the proper design of thermosyphons for dedicated applications by providing information about the heat transport capability for different thermosyphon design parameters.

Timinger, H.; David, B.; Eckart, R.; Overweg, J.

2008-03-01

117

Spacelab cryogenic propellant management experiment  

NASA Technical Reports Server (NTRS)

The conceptual design of a Spacelab cryogen management experiment was performed to demonstrate toe desirability and feasibility of subcritical cryogenic fluid orbital storage and supply. A description of the experimental apparatus, definition of supporting requirements, procedures, data analysis, and a cost estimate are included.

Cady, E. C.

1976-01-01

118

Cryogenic insulation development  

NASA Technical Reports Server (NTRS)

Multilayer insulations for long term cryogenic storage are described. The development effort resulted in an insulation concept using lightweight radiation shields, separated by low conductive Dacron fiber tufts. The insulation is usually referred to as Superfloc. The fiber tufts are arranged in a triangular pattern and stand about .040 in. above the radiation shield base. Thermal and structural evaluation of Superfloc indicated that this material is a strong candidate for the development of high performance thermal protection systems because of its high strength, purge gas evacuation capability during boost, its density control and easy application to a tank.

Leonhard, K. E.

1972-01-01

119

Cryogenic support member  

DOEpatents

A cryogenic support member is comprised of a non-metallic rod having a depression in at least one end and a metallic end connection assembled to the rod. The metallic end connection comprises a metallic plug which conforms to the shape and is disposed in the depression and a metallic sleeve is disposed over the rod and plug. The plug and the sleeve are shrink-fitted to the depression in the rod to form a connection good in compression, tension and bending.

Niemann, Ralph C. (Downers Grove, IL); Gonczy, John D. (Oak Lawn, IL); Nicol, Thomas H. (Aurora, IL)

1987-01-01

120

Flexible cryogenic thermosyphon  

NASA Astrophysics Data System (ADS)

Cryocooler and pulse tubes have been increasingly used in small and large scale cryogenic systems including the superconducting magnet systems as heat sinks to attain and keep the required temperatures. Designing the thermal link between the mechanical refrigerator and the system may present a challenge due to the mechanical stresses developed during the cool-down of the assembled systems. Also, the cross section may be too bulky for metallic conductors for given thermal specifications. In this paper, a thermosysphon with a flexible fluid link between the evaporator and condenser is presented. The working fluid used in preliminary testing is nitrogen. The results of the initial testing of the flexible thermosyphon are presented.

Celik, Dogan; Painter, Thomas

2012-06-01

121

FRIB cryogenic distribution system  

NASA Astrophysics Data System (ADS)

The Michigan State University Facility for Rare Isotope Beams (MSU-FRIB) helium distribution system has been revised to include bayonet/warm valve type disconnects between each cryomodule and the transfer line distribution system, similar to the Thomas Jefferson National Accelerator Facility (JLab) and the Spallation Neutron Source (SNS) cryogenic distribution systems. The heat loads at various temperature levels and some of the features in the design of the distribution system are outlined. The present status, the plans for fabrication, and the procurement approach for the helium distribution system are also included.

Ganni, V.; Dixon, K.; Laverdure, N.; Knudsen, P.; Arenius, D.; Barrios, M.; Jones, S.; Johnson, M.; Casagrande, F.

2014-01-01

122

Nuclear Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced NEP.

Houts, Michael G.; Borowski, S. K.; George, J. A.; Kim, T.; Emrich, W. J.; Hickman, R. R.; Broadway, J. W.; Gerrish, H. P.; Adams, R. B.

2012-01-01

123

Cryogenic distribution for the Facility for Rare Isotope Beams  

NASA Astrophysics Data System (ADS)

The Facility for Rare Isotope Beams (FRIB) is a new National User Facility for nuclear science funded by the Department of Energy Office of Science and operated by Michigan State University. The FRIB accelerator linac consists of superconducting radio-frequency (SCRF) cavities operating at 2 K and SC magnets operating at 4.5 K all cooled by a large scale cryogenic refrigeration system. A major subsystem of the cryogenic system will be the distribution system whose primary components will include a distribution box, the transfer lines and the interconnect valve boxes at each cryogenic device. An overview of the conceptual design of the distribution system including engineering details, capabilities and schedule is described.

Jones, S.; Arenius, Dana; Fila, Adam; Geutschow, P.; Laumer, Helmut; Johnson, Matt; Waltz, Cory S.; Weisend, J. G., II

2012-06-01

124

Demonstration of noble gas collection using the cryogenic technique  

SciTech Connect

Monitoring devices used for detecting and measuring airborne radioactive noble gases in stack emissions have been limited in their precision and detection capability. Cryogenic sampling is one method used for sampling gamma emitting radioactive gases in stack emissions. A cryogenic air sampler, originally developed at the Oak Ridge National Laboratory (ORNL) and further developed by the Systems Demonstration and Environmental Air Sampling Group (SDEASG) at the Oak Ridge Gaseous Diffusion Plant (ORGDP) is being tested. The cryogenic sampler will be used to study the off-gas from various emission points at ORNL after completion of the preliminary study by SDEASG. Work is currently under way to demonstrate the effectiveness of the sampler and the efficiency of the sampling method. Various tests have been and are being conducted to determine the sample collection techniques which will result in the greatest sample transfer efficiency, sampling precision, and gamma emission counting efficiencies. 4 figs., 2 tabs.

Moser, L.V.; Delzer, D.B.

1988-09-01

125

Cryogenic Piezoelectric Actuator  

NASA Technical Reports Server (NTRS)

In this paper, PMN-PT single crystal piezoelectric stack actuators and flextensional actuators were designed, prototyped and characterized for space optics applications. Single crystal stack actuators with footprint of 10 mm x10 mm and the height of 50 mm were assembled using 10 mm x10mm x0.15mm PMN-PT plates. These actuators showed stroke > 65 - 85 microns at 150 V at room temperature, and > 30 microns stroke at 77 K. Flextensional actuators with dimension of 10mm x 5 mm x 7.6 mm showed stroke of >50 microns at room temperature at driving voltage of 150 V. A flextensional stack actuator with dimension of 10 mm x 5 mm x 47 mm showed stroke of approx. 285 microns at 150 V at room temperature and > 100 microns at 77K under driving of 150 V should be expected. The large cryogenic stroke and high precision of these actuators are promising for cryogenic optics applications.

Jiang, Xiaoning; Cook, William B.; Hackenberger, Wesley S.

2009-01-01

126

Cryogenic optical lattice clocks  

NASA Astrophysics Data System (ADS)

The accuracy of atomic clocks relies on the superb reproducibility of atomic spectroscopy, which is accomplished by careful control and the elimination of environmental perturbations on atoms. To date, individual atomic clocks have achieved a 10?18 level of total uncertainties, but a two-clock comparison at the 10?18 level has yet to be demonstrated. Here, we demonstrate optical lattice clocks with 87Sr atoms interrogated in a cryogenic environment to address the blackbody radiation-induced frequency shift, which remains the primary source of systematic uncertainty and has initiated vigorous theoretical and experimental investigations. The systematic uncertainty for the cryogenic clock is evaluated to be 7.2?×?10?18, which is expedited by operating two such cryo-clocks synchronously. After 11 measurements performed over a month, statistical agreement between the two cryo-clocks reached 2.0?×?10?18. Such clocks' reproducibility is a major step towards developing accurate clocks at the low 10?18 level, and is directly applicable as a means for relativistic geodesy.

Ushijima, Ichiro; Takamoto, Masao; Das, Manoj; Ohkubo, Takuya; Katori, Hidetoshi

2015-03-01

127

Design and Construction of Cryogenic Optomechanical System  

NASA Astrophysics Data System (ADS)

One key challenge to observing quantum phenomena in a macroscopic mechanical oscillator is reaching its ground state. To achieve the low temperatures required for this, we utilize resolved sideband laser cooling of a few hundred kHz mechanical oscillator with high mechanical Q (a Si3N4 membrane) inside a high finesse optical cavity, in addition to cryogenically reducing the bath temperature. Realizing high Q and high finesse cavity optomechanical devices in a cryogenic environment requires overcoming a number of challenges. In this talk, we describe the design and construction of such a device working at a bath temperature of 300 mK (in a 3He refrigerator) and suited for operation at lower temperatures (in a dilution refrigerator). The design incorporates in-situ commercial piezo actuators (manufactured by Janssen Precision Engineering) to couple externally prepared laser light into the cold optical cavity. The design also incorporates filtering cavities to suppress classical laser noise, and acoustic and seismic isolation of the experiment.

Lee, Donghun; Underwood, Mitchell; Mason, David; Jayich, Andrew; Kashkanova, Anya; Harris, Jack

2013-03-01

128

Cryogenic Cooling for Myriad Applications-A STAR Is Born  

NASA Technical Reports Server (NTRS)

Cryogenics, the science of generating extremely low temperatures, has wide applicability throughout NASA. The Agency employs cryogenics for rocket propulsion, high-pressure gas supply, breathable air in space, life support equipment, electricity, water, food preservation and packaging, medicine, imaging devices, and electronics. Cryogenic liquid oxygen and liquid hydrogen systems are also replacing solid rocket motor propulsion systems in most of the proposed launch systems, a reversion to old-style liquid propellants. In the late 1980s, NASA wanted a compact linear alternator/motor with reduced size and mass, as well as high efficiency, that had unlimited service life for use in a thermally driven power generator for space power applications. Prior development work with free-piston Stirling converters (a Stirling engine integrated with a linear actuator that produces electrical power output) had shown the promise of that technology for high-power space applications. A dual use for terrestrial applications exists for compact Stirling converters for onsite combined heat and power units. The Stirling cycle is also usable in reverse as a refrigeration cycle suitable for cryogenic cooling, so this Stirling converter work promised double benefits as well as dual uses. The uses for cryogenic coolers within NASA abound; commercial applications are similarly wide-ranging, from cooling liquid oxygen and nitrogen, to cryobiology and bio-storage, cryosurgery, instrument and detector cooling, semiconductor manufacturing, and support service for cooled superconducting power systems.

2006-01-01

129

Cryogenic insulation strength and bond tester  

NASA Technical Reports Server (NTRS)

A method and apparatus for testing the tensile strength and bonding strength of sprayed-on foam insulation attached to metal cryogenic fuel tanks is described. A circular cutter is used to cut the insulation down to the surface of the metal tank to form plugs of the insulation for testing in situ on the tank. The apparatus comprises an electromechanical pulling device powered by a belt battery pack. The pulling device comprises a motor driving a mechanical pulling structure comprising a horizontal shaft connected to two bell cracks which are connected to a central member. When the lower end of member is attached to a fitting, which in turn is bonded to a plug, a pulling force is exerted on the plug sufficient to rupture it. The force necessary to rupture the plug or pull it loose is displayed as a digital read-out.

Schuerer, P. H.; Ehl, J. H.; Prasthofer, W. P. (inventors)

1985-01-01

130

Cryogenic Fluid Transfer for Exploration  

NASA Technical Reports Server (NTRS)

This paper discusses current plans and issues for exploration that involve the use of cryogenic transfer. The benefits of cryogenic transfer to exploration missions are examined. The current state of the art of transfer technology is reviewed. Mission concepts of operation for exploration are presented, and used to qualitatively discuss the performance benefits of transfer. The paper looks at the challenges faced to implement a cryogenic transfer system and suggest approaches to address them with advanced development research. Transfer rates required for exploration are shown to have already been achieved in ground test. Cost effective approaches to the required on-orbit demonstration are suggested.

Chato, David J.

2007-01-01

131

Cryogenic Fluid Transfer for Exploration  

NASA Technical Reports Server (NTRS)

This paper discusses current plans and issues for exploration that involve the use of cryogenic transfer. The benefits of cryogenic transfer to exploration missions are examined. The current state of the art of transfer technology is reviewed. Mission concepts of operation for exploration are presented, and used to qualitatively discuss the performance benefits of transfer. The paper looks at the challenges faced to implement a cryogenic transfer system and suggest approaches to address them with advanced development research. Transfer rates required for exploration are shown to have already been achieved in ground test. Cost-effective approaches to the required on-orbit demonstration are suggested.

Chato, David J.

2008-01-01

132

Cryogenic cooler apparatus  

DOEpatents

A Malone-type final stage for utilization in a Stirling cycle cryogenic cooler apparatus includes a displacer slidable within a vessel. .sup.4 He, .sup.3 He, or a mixture thereof is made to flow in a pulsating unidirectional manner through a regenerator in the displacer by utilization of check valves in separate fluid channels. Stacked copper screen members extend through the channels and through a second static thermodynamic medium within the displacer to provide efficient lateral heat exchange and enable cooling to temperatures in the range of 3-4 K. Another embodiment utilizes sintered copper particles in the regenerator. Also described is a final stage that has a non-thermally conducting displacer having passages with check valves for directing fluid past a regenerator formed in the surrounding vessel.

Wheatley, John C. (Del Mar, CA); Paulson, Douglas N. (Del Mar, CA); Allen, Paul C. (Sunnyvale, CA)

1983-01-01

133

Cryogenic cooler apparatus  

DOEpatents

A Malone-type final stage for utilization in a Stirling cycle cryogenic cooler apparatus includes a displacer slidable within a vessel. [sup 4]He, [sup 3]He, or a mixture thereof is made to flow in a pulsating unidirectional manner through a regenerator in the displacer by utilization of check valves in separate fluid channels. Stacked copper screen members extend through the channels and through a second static thermodynamic medium within the displacer to provide efficient lateral heat exchange and enable cooling to temperatures in the range of 3--4 K. Another embodiment utilizes sintered copper particles in the regenerator. Also described is a final stage that has a non-thermally conducting displacer having passages with check valves for directing fluid past a regenerator formed in the surrounding vessel. 10 figs.

Wheatley, J.C.; Paulson, D.N.; Allen, P.C.

1983-01-04

134

Cryogenic nuclear gyroscope  

SciTech Connect

A cryogenic nuclear gyroscope is described that is comprised of a cylinder of niobium cooled within a helium cryostat so as to be superconducting and to provide a trapped, substantially homogeneous magnetic field, a helium-3 sample contained within a spherical pyrex cell having nuclei possessing a net magnetic moment, coils provided to polarize the sample to provide that net magnetic moment, and a SQUID magnetometer coupled to the sample by a pick-up coil of a transformer and frequency sensitive means coupled to the SQUID to detect changes in the precession of the nuclear moments of the sample caused by rotation of the gyroscope about an axis parallel to the direction of the homogeneous magnetic field. A superconducting lead shield isolates the helium-3 sample from external magnetic fields.

Gallop, J.C.; Potts, S.P.

1980-09-30

135

High Temperature Superconducting Space Experiment II (HTSSE II) cryogenic design  

NASA Astrophysics Data System (ADS)

At 60 to 80 K large performance gains are possible from high temperature superconducting (HTS) microwave devices for communications applications. The High Temperature Superconducting Space Experiment II (HTSSE II) will demonstrate eight HTS experiments in space for up to 3 years of operation. HTSSE II is the first application of HTS technology to space. In addition to demonstrating HTS devices, an important secondary goal is to demonstrate the cryogenic technologies required for long life HTS space applications. HTSSE II utilizes a British Aerospace 80 K Stirling cycle cryocooler to refrigerate a central cryogenic bus of seven HTS experiments and has an additional stand-alone TRW HTS experiment cooled by a TRW Stirling cycle cryocooler. The HTSSE II flight unit has been assembled and has successfully passed vibration and thermal vacuum environmental tests. HTSSE II was developed on a fixed budget and a fast track schedule of 24 months and is due to launch in March 1997 on the ARGOS spacecraft. This paper presents the design and test results of the cryogenic subsystem, cryocooler integration and a cryogenic coaxial cable I/O assembly.

Kawecki, T. G.; Chappie, S. S.; Mahony, D. R.

136

Improved cryogenic aluminum mirrors  

NASA Astrophysics Data System (ADS)

Optical surface deformation of metal mirrors used at cryogenic temperatures is reduced through the use of a new process of plating amorphous aluminum on aluminum. The AlumiPlateTM process (produced by AlumiPlate, Inc. in Minneapolis, MN) plates a layer of 99.9+% high purity aluminum about 125 micrometers thick atop the substrate. Very good surface finishes are produced by direct diamond turning of the plating, with some samples below 40 angstroms RMS. Optical testing of a 175-mm diameter, 550-mm optical radius of curvature 6061-T651/AlumiPlateTM aluminum sphere was performed at 65 K to determine cryogenic optical surface figure stability. In five cycles from 300 to 65 K, an average optical surface change of 0.047 wave RMS (1 wave equals 633 nm) was observed. A total optical figure change of 0.03 wave RMS at 65 K was observed from the first to last cycle. The cause of this relatively small long-term change is not yet determined. The test mirror is bi-concave, with a semi- kinematic toroidal mount, and is machined from the axis of a billet. An `uphill quench' heat treatment consisting of five cycles from liquid nitrogen to boiling water temperatures is used to minimize residual stress in the test mirror. Initial diamond turning of the mirror by the Optical Filter Corp., Keene, NH, produced a 300 K unmounted optical surface figure of 0.380 wave peak-to-valley and 0.059 wave RMS. A second effort at diamond turning by II-VI, Inc., Saxonburg, PA produced a 300 K optical figure of 0.443 wave peak-to-valley and 0.066 wave RMS, with a surface roughness varying from 29 to 42 angstroms.

Vukobratovich, Daniel; Don, Ken; Sumner, Richard E.

1998-09-01

137

Main Consolidations and Improvements of the Control System and Instrumentation for the LHC Cryogenics  

E-print Network

Operation of the LHC during 2010 and 2011 with 3.5 TeV beam energy and luminosity up to 3.65x1033 cm-2 s-1, led to radiation-induced failures of micro-electronic devices used in the cryogenic control system. Mitigating actions addressed equipment relocation and corrective patches on electronics and software. Driven by the technical requirements and by feedback from the cryogenic operation team, numerous consolidations and improvements were implemented on-the-fly, enhancing availability and operability of the LHC cryogenics. Furthermore, additional diagnostic tools, test benches, technical procedures and trainings have been provided to strengthen first line support services.

Fluder, C; Bremer, J; Bremer, K; Ivens, B; Casas-Cubillos, J; Claudet, S; Gomes, P; Ivens, B; Perin, A; Pezzetti, M; Tovar-Gonzalez, A; Vauthier, N

2013-01-01

138

Introduction to cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

The background to the evolution of the cryogenic wind tunnel is outlined, with particular reference to the late 60's/early 70's when efforts were begun to re-equip with larger wind tunnels. The problems of providing full scale Reynolds numbers in transonic testing were proving particularly intractible, when the notion of satisfying the needs with the cryogenic tunnel was proposed, and then adopted. The principles and advantages of the cryogenic tunnel are outlined, along with guidance on the coolant needs when this is liquid nitrogen, and with a note on energy recovery. Operational features of the tunnels are introduced with reference to a small low speed tunnel. Finally the outstanding contributions are highlighted of the 0.3-Meter Transonic Cryogenic Tunnel (TCT) at NASA Langley Research Center, and its personnel, to the furtherance of knowledge and confidence in the concept.

Goodyer, M. J.

1985-01-01

139

Superconducting thermometer for cryogenics  

NASA Technical Reports Server (NTRS)

Digital electronic device uses superconducting filaments as sensors. Simple solid-state circuitry combined with filaments comprise highly-reliable temperature monitor. Device has ability to track very fast thermal transients and "on/off" output is adaptable to remote sensing and telemetry.

White, F. A.

1977-01-01

140

Tokamak15 cryogenic system-the results of design and experimental analysis-the experience data  

Microsoft Academic Search

The Tokamak-15 cryogenic system is the largest helium system operated in the USSR and comprises two subsystems: nitrogen and helium. The cryogenic helium system is designed for cooldown and steady-state operation of superconducting coils of the TF 300 t magnetic system and the devices of plasma additional heating, and the nitrogen system is designed for steady-state operation of shields, cryostat

I. K. Butkevitch; S. I. Veremuchuk; Y. I. Duhanin; V. D. Kovalenko; V. V. Krylov; Y. V. Alexandrov; V. E. Duzhev; V. P. Zhulkin; G. M. Kashirskih; A. E. Ugrovatov

1992-01-01

141

Cryogenic High Pressure Sensor Module  

NASA Technical Reports Server (NTRS)

A pressure sensor is provided for cryogenic, high pressure applications. A highly doped silicon piezoresistive pressure sensor is bonded to a silicon substrate in an absolute pressure sensing configuration. The absolute pressure sensor is bonded to an aluminum nitride substrate. Aluminum nitride has appropriate coefficient of thermal expansion for use with highly doped silicon at cryogenic temperatures. A group of sensors, either two sensors on two substrates or four sensors on a single substrate are packaged in a pressure vessel.

Chapman, John J. (Inventor); Shams, Qamar A. (Inventor); Powers, William T. (Inventor)

1999-01-01

142

Cryogenic, Absolute, High Pressure Sensor  

NASA Technical Reports Server (NTRS)

A pressure sensor is provided for cryogenic, high pressure applications. A highly doped silicon piezoresistive pressure sensor is bonded to a silicon substrate in an absolute pressure sensing configuration. The absolute pressure sensor is bonded to an aluminum nitride substrate. Aluminum nitride has appropriate coefficient of thermal expansion for use with highly doped silicon at cryogenic temperatures. A group of sensors, either two sensors on two substrates or four sensors on a single substrate are packaged in a pressure vessel.

Chapman, John J. (Inventor); Shams. Qamar A. (Inventor); Powers, William T. (Inventor)

2001-01-01

143

A Piezoelectric Cryogenic Heat Switch  

NASA Technical Reports Server (NTRS)

We have measured the thermal conductance of a mechanical heat switch actuated by a piezoelectric positioner, the PZHS (PieZo electric Heat Switch), at cryogenic temperatures. The thermal conductance of the PZHS was measured between 4 K and 10 K, and on/off conductance ratios greater than 100 were achieved when the positioner applied its maximum force of 8 N. We discuss the advantages of using this system in cryogenic applications, and estimate the ultimate performance of an optimized PZHS.

Jahromi, Amir E.; Sullivan, Dan F.

2014-01-01

144

Cryogenic foam insulation: Abstracted publications  

NASA Technical Reports Server (NTRS)

A group of documents were chosen and abstracted which contain information on the properties of foam materials and on the use of foams as thermal insulation at cryogenic temperatures. The properties include thermal properties, mechanical properties, and compatibility properties with oxygen and other cryogenic fluids. Uses of foams include applications as thermal insulation for spacecraft propellant tanks, and for liquefied natural gas storage tanks and pipelines.

Williamson, F. R.

1977-01-01

145

Polyamide 66 as a Cryogenic Dielectric  

SciTech Connect

Improvements in superconductor and cryogenic technologies enable novel power apparatus, \\eg, cables, transformers, fault current limiters, generators, \\etc, with better device characteristics than their conventional counterparts. In these applications electrical insulation materials play an important role in system weight, footprint (size), and voltage level. The trend in the electrical insulation material selection has been to adapt or to employ conventional insulation materials to these new systems. However, at low temperatures, thermal contraction and loss of mechanical strength in many materials make them unsuitable for superconducting power applications. In this paper, a widely used commercial material was characterized as a potential cryogenic dielectric. The material is used in ``oven bag'' a heat-resistant polyamide (nylon) used in cooking (produced by Reynolds\\textregistered, Richmond, VA, USA). It is first characterized by Fourier transform infrared and x-ray diffraction techniques and determined to be composed of polyamide 66 (PA66) polymer. Secondly the complex dielectric permittivity and dielectric breakdown strength of the PA66 films are investigated. The dielectric data are then compared with data reported in the literature. A comparison of dielectric strength with a widely used high-temperature superconductor electrical insulation material, polypropylene-laminated paper (PPLP\\texttrademark\\ a product of Sumitomo Electric Industries, Japan), is provided. It is observed that the statistical analysis of the PA66 films yields 1\\% failure probability at $127\\ \\kilo\\volt\\milli\\meter^{-1}$; this value is approximately $46\\ \\kilo\\volt\\milli\\meter^{-1}$ higher than PPLP\\texttrademark. It is concluded that PA66 may be a good candidate for cryogenic applications. Finally, a summary of dielectric properties of some of the commercial tape insulation materials and various polymers is also provided.

Tuncer, Enis [ORNL; Polyzos, Georgios [ORNL; Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Messman, Jamie M [ORNL; Aytug, Tolga [ORNL

2009-01-01

146

Experimental Observations on Material Damping at Cryogenic Temperatures  

NASA Technical Reports Server (NTRS)

This paper describes a unique experimental facility designed to measure damping of materials at cryogenic temperatures for the Terrestrial Planet Finder (TPF) mission at the Jet Propulsion Laboratory. The test facility removes other sources of damping in the measurement by avoiding frictional interfaces, decoupling the test specimen from the support system, and by using a non-contacting measurement device. Damping data reported herein are obtained for materials (Aluminum, Aluminum/Terbium/Dysprosium, Titanium, Composites) vibrating in free-free bending modes with low strain levels (< 10(exp -6) ppm). The fundamental frequencies of material samples are ranged from 14 to 202 Hz. To provide the most beneficial data relevant to TPF-like precision optical space missions, the damping data are collected from room temperatures (around 293 K) to cryogenic temperatures (below 40 K) at unevenly-spaced intervals. More data points are collected over any region of interest. The test data shows a significant decrease in viscous damping at cryogenic temperatures. The cryogenic damping can be as low as 10(exp -4) %, but the amount of the damping decrease is a function of frequency and material. However, Titanium 15-3-3-3 shows a remarkable increase in damping at cryogenic temperatures. It demonstrates over one order of magnitude increase in damping in comparison to Aluminum 6061-T6. Given its other properties (e.g., good stiffness and low conductivity) this may prove itself to be a good candidate for the application on TPF. At room temperatures, the test data are correlated well with the damping predicted by the Zener theory. However, large discrepancies at cryogenic temperatures between the Zener theory and the test data are observed.

Peng, Chia-Yen; Levine, Marie; Shido, Lillian; Leland, Robert

2004-01-01

147

Cryogenic focussing, ohmically heated on-column trap  

SciTech Connect

A procedure is described for depositing a conductive layer of gold on the exterior of a fused-silica capillary used in gas chromatography. By subjecting a section of the column near the inlet to a thermal cycle of cryogenic cooling and ohmic heating, volatile samples are concentrated and subsequently injected. The performance of this trap as a chromatographic injector is demonstrated. Several additional applications are suggested and the unique properties of this device are discussed. 11 refs., 5 figs., 1 tab.

Springston, S.R.

1991-12-01

148

Cryogenic focussing, ohmically heated on-column trap  

NASA Technical Reports Server (NTRS)

A procedure is described for depositing a conductive layer of gold on the exterior of a fused-silica capillary used in gas chromatography. By subjecting a section of the column near the inlet to a thermal cycle of cryogenic cooling and ohmic heating, volatile samples are concentrated and subsequently injected. The performance of this trap as a chromatographic injector is demonstrated. Several additional applications are suggested and the unique properties of this device are discussed.

Springston, Stephen R.

1991-01-01

149

Expander stroke delay mechanism for split Stirling cryogenic cooler  

SciTech Connect

This invention comprises a cryogenic cooling device operating in the manner of a split Stirling cycle engine whereby a sinusoidal pressure-wave generator distal to a regenerator displacer piston and accompanying cylinder, individually compresses in a delayed manner and expands a contained volume of gas in an expander housing respective to regenerator displacer piston travel to bring about a cooling effect in an attached displacer housing.

Robbins, R.W.

1982-03-26

150

Cryogenic Neutron Spectrometer Development  

SciTech Connect

Cryogenic microcalorimeter detectors operating at temperatures around {approx}0.1 K have been developed for the last two decades, driven mostly by the need for ultra-high energy resolution (<0.1%) in X-ray astrophysics and dark matter searches [1]. The Advanced Detector Group at Lawrence Livermore National Laboratory has developed different cryogenic detector technologies for applications ranging from X-ray astrophysics to nuclear science and non-proliferation. In particular, we have adapted cryogenic detector technologies for ultra-high energy resolution gamma-spectroscopy [2] and, more recently, fast-neutron spectroscopy [3]. Microcalorimeters are essentially ultra-sensitive thermometers that measure the energy of the radiation from the increase in temperature upon absorption. They consist of a sensitive superconducting thermometer operated at the transition between its superconducting and its normal state, where its resistance changes very rapidly with temperature such that even the minute energies deposited by single radiation quanta are sufficient to be detectable with high precision. The energy resolution of microcalorimeters is fundamentally limited by thermal fluctuations to {Delta}E{sub FWHM} {approx} 2.355 (k{sub B}T{sup 2}C{sub abs}){sup 1/2}, and thus allows an energy below 1 keV for neutron spectrometers for an operating temperature of T {approx} 0.1 K . The {Delta}E{sub FWHM} does not depend on the energy of the incident photon or particle. This expression is equivalent to the familiar (F{var_epsilon}E{sub {gamma}}){sup 1/2} considering that an absorber at temperature T contains a total energy C{sub abs}T, and the associated fluctuation are due to variations in uncorrelated (F=1) phonons ({var_epsilon} = k{sub B}T) dominated by the background energy C{sub abs}T >> E{gamma}. The rationale behind developing a cryogenic neutron spectrometer is the very high energy resolution combined with the high efficiency. Additionally, the response function is simple and the instrument is transportable. We are currently developing a fast neutron spectrometer with 0.1% energy resolution at 1 MeV neutron energy with an efficiency of > 1%. Our fast-neutron spectrometers use boron-based and {sup 6}LiF absorber crystals with Mo/Cu thermistors readout. They have achieved an energy resolution of 5.5 keV FWHM for 2.79 MeV deposited in {sup 10}B by thermal neutron capture (fig. 1), and 46 keV FWHM for fast (MeV) neutrons absorbed in {sup 6}LiF (fig. 2). Since the energy resolution does not depend on the neutron energy, we expect a similar energy resolution for MeV neutron energies. The response function is given simply by the cross section of the capture reaction, offset from zero by the Q-value of the capture reaction. This allows straightforward discrimination against gamma-events, most of which deposit less that Q{sub 6Li} = 4.79 MeV in the {sup 6}LiF absorber, and easy deconvolution of the neutron spectrum, since there is only a single capture reaction in {sup 6}Li and the spectrum is not affected by edge effects or geometric broadening. The current challenge for microcalorimeters is their necessarily small effective pixel area, {approx}1cm{sup 3} for neutron spectrometer pixels, and their slow decay time, {approx}10ms for neutron spectrometers. The pixel size is limited by the requirement for low Cabs for high energy resolution; the decay time is set by the intrinsically weak thermal coupling between materials at low temperatures. Both issues can be addressed by fabricating large detector arrays. This will enable high-precision neutron spectrometry with high statistics, such as simulated for Pu analysis in fig 3.

Niedermayr, T; Hau, I D; Friedrich, S; Burger, A; Roy, U N; Bell, Z W

2006-03-08

151

Collapsible Cryogenic Storage Vessel Project  

NASA Technical Reports Server (NTRS)

Collapsible cryogenic storage vessels may be useful for future space exploration missions by providing long-term storage capability using a lightweight system that can be compactly packaged for launch. Previous development efforts have identified an 'inflatable' concept as most promising. In the inflatable tank concept, the cryogen is contained within a flexible pressure wall comprised of a flexible bladder to contain the cryogen and a fabric reinforcement layer for structural strength. A flexible, high-performance insulation jacket surrounds the vessel. The weight of the tank and the cryogen is supported by rigid support structures. This design concept is developed through physical testing of a scaled pressure wall, and through development of tests for a flexible Layered Composite Insulation (LCI) insulation jacket. A demonstration pressure wall is fabricated using Spectra fabric for reinforcement, and burst tested under noncryogenic conditions. An insulation test specimens is prepared to demonstrate the effectiveness of the insulation when subject to folding effects, and to examine the effect of compression of the insulation under compressive loading to simulate the pressure effect in a nonrigid insulation blanket under the action atmospheric pressure, such as would be seen in application on the surface of Mars. Although pressure testing did not meet the design goals, the concept shows promise for the design. The testing program provides direction for future development of the collapsible cryogenic vessel concept.

Fleming, David C.

2002-01-01

152

Cryogenically assisted abrasive jet micromachining of polymers  

NASA Astrophysics Data System (ADS)

The abrasive jet micromachining (AJM) of elastomers and polymers such as polydimethylsiloxane (PDMS), acrylonitrile butadiene styrene (ABS) and polytetrafluoroethylene (PTFE) for use in micro-fluidic devices was found to be very slow or impossible at room temperature. To enhance the material removal rate in such materials, a stream of liquid nitrogen (LN2) was injected into the abrasive jet, cooling the target to cryogenic temperatures. Erosion rate measurements on the three polymeric materials (PDMS, ABS and PTFE) with and without the use of LN2 were compared along with the profiles of micromachined channels and holes. It was found that the use of LN2 cooling caused brittle erosion in PDMS, allowing it to be micromachined successfully. An erosion rate increase was also observed in PTFE and ABS at high and intermediate impact angles. The use of LN2 also was found to reduce particle embedding.

Getu, H.; Spelt, J. K.; Papini, M.

2008-11-01

153

Modeling of cryogen leakage through composite laminates  

E-print Network

Cryogenic composites ?nd critical application in the manufacture of fuel tanks for reusable launch vehicles due to signi?cant reduction in overall structural weight of the tank. These fuel tanks contain pressurized cryogen...

Peddiraju, Naga Venkata Satya Pravin Kumar

2005-02-17

154

Analysis of the cryogenic system behavior for pulsed heat load in EAST  

NASA Astrophysics Data System (ADS)

EAST is the first full superconducting fusion device. The plasma is confined by the magnetic fields generated from a large set of superconducting magnets which are made of cable in-conduit conductor (CICC). In operation, these magnets suffer heat loads from thermal and nuclear radiation from the surrounding components and plasma as well as the eddy currents and the AC losses generated within the magnets, together with the heat conduction through supports and the resistive heat generated at the current lead transiting to room temperature. The cryogenic system of our EAST consists of a 2kW/4K helium refrigerator and a distribution system for the cooling of poloidal field (PF) and toroidal field (TF) coils, structures, thermal shields, buslines and current leads. Pulsed heat load is the main difference between the cryogenic system of a full superconducting Tokamak system and other large scale cryogenic systems. The cryogenic system operates in a pulsed heat loads mode requiring the helium refrigerator to remove periodically large heat loads in time. At the same time, the cryogenic system parameters such as helium cooling superconducting magnets, helium refrigerator and helium distribution system are changing. In this paper, the variation range of the parameters of superconducting magnets and refrigerator has been analyzed in the typical plasma discharge mode. The control scheme for the pulsed loads characteristics of the cryogenic system has been proposed, the implementation of which helps to smooth the pulse loads and to improve the stability of the operation of the cryogenic system.

Hu, L. B.; Zhuang, M.; Zhou, Z. W.; Xia, G. H.

2014-01-01

155

Analysis of the cryogenic system behavior for pulsed heat load in EAST  

SciTech Connect

EAST is the first full superconducting fusion device. The plasma is confined by the magnetic fields generated from a large set of superconducting magnets which are made of cable in-conduit conductor (CICC). In operation, these magnets suffer heat loads from thermal and nuclear radiation from the surrounding components and plasma as well as the eddy currents and the AC losses generated within the magnets, together with the heat conduction through supports and the resistive heat generated at the current lead transiting to room temperature. The cryogenic system of our EAST consists of a 2kW/4K helium refrigerator and a distribution system for the cooling of poloidal field (PF) and toroidal field (TF) coils, structures, thermal shields, buslines and current leads. Pulsed heat load is the main difference between the cryogenic system of a full superconducting Tokamak system and other large scale cryogenic systems. The cryogenic system operates in a pulsed heat loads mode requiring the helium refrigerator to remove periodically large heat loads in time. At the same time, the cryogenic system parameters such as helium cooling superconducting magnets, helium refrigerator and helium distribution system are changing. In this paper, the variation range of the parameters of superconducting magnets and refrigerator has been analyzed in the typical plasma discharge mode. The control scheme for the pulsed loads characteristics of the cryogenic system has been proposed, the implementation of which helps to smooth the pulse loads and to improve the stability of the operation of the cryogenic system.

Hu, L. B.; Zhuang, M.; Zhou, Z. W.; Xia, G. H. [Cryogenic Engineering Division, Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Shushanhu Road 350, Hefei, Anhui 230031 (China)

2014-01-29

156

Advances in Cryogenic Avalanche Detectors  

E-print Network

Cryogenic Avalanche Detectors (CRADs) are referred to as a new class of noble-gas detectors operated at cryogenic temperatures with electron avalanching performed directly in the detection medium, the latter being in gaseous, liquid or two-phase (liquid-gas) state. Electron avalanching is provided by Micro-Pattern Gas Detector (MPGD) multipliers, in particular GEMs and THGEMs, operated at cryogenic temperatures in dense noble gases. The final goal for this kind of detectors is the development of large-volume detectors of ultimate sensitivity for rare-event experiments and medical applications, such as coherent neutrino-nucleus scattering, direct dark matter search, astrophysical (solar and supernova) neutrino detection experiments and Positron Emission Tomography technique. This review is the first attempt to summarize the results on CRAD performances obtained by different groups. A brief overview of the available CRAD concepts is also given and the most remarkable CRAD physics effects are discussed.

A. Buzulutskov

2015-03-29

157

Other Cryogenic Wind Tunnel Projects  

NASA Technical Reports Server (NTRS)

The first cryogenic tunnel was built at the NASA Langley Research Center in 1972. Since then, many cryogenic wind-tunnels have been built at aeronautical research centers around the world. In this lecture some of the more interesting and significant of these projects that have not been covered by other lecturers at this Special Course are described. In this lecture authors describe cryogenic wind-tunnel projects at research centers in four countries: China (Chinese Aeronautical Research and Development Center); England (College of Aeronautics at Cranfield, and Defence Research Agency - Bedford); Japan (National Aerospace Laboratory, University of Tsukuba, and National Defense Academy); and United States (Douglas Aircraft Co., University of Illinois at Urbana-Champaign, and NASA Langley).

Kilgore, Robert A.

1997-01-01

158

Other cryogenic wind tunnel projects  

NASA Technical Reports Server (NTRS)

The first cryogenic tunnel was built in 1972. Since then, many cryogenic wind-tunnel projects were started at aeronautical research centers around the world. Some of the more significant of these projects are described which are not covered by other lecturers at this Special Course. Described are cryogenic wind-tunnel projects in five countries: China (Chinese Aeronautical Research and Development Center); England (College of Aeronautics at Cranfield, and Royal Aerospace Establishment-Bedford); Japan (National Aerospace Laboratory, University of Tsukuba, and National Defense Academy); United States (Douglas Aircraft Co., University of Illinois at Urbana-Champaign and NASA Langley); and U.S.S.R. (Central Aero-Hydronamics Institute (TsAGI), Institute of Theoretical and Applied Mechanics (ITAM), and Physical-Mechanical Institute at Kharkov (PMI-K).

Kilgore, Robert A.

1989-01-01

159

Latest developments in cryogenic safety  

NASA Astrophysics Data System (ADS)

The Cryogenic Safety Manual, published under the auspices of the British Cryogenics Council, is summarized. Since an awareness of the physical properties of the cryogenic fluids being dealt with is considered important in directing attention to hazardous situations which may arise, the manual lists the more important properties, such as molecular weight, boiling point, and freezing point. Since hydrogen and helium are very light, the possibility arises of explosive mixtures being formed at high points in buildings. Since argon is unexpectedly heavy, its removal requires suction rather than blowing. It is also pointed out that the use of inert liquid nitrogen can lead to the creation of a noninert atmosphere which supports combustion because it contains oxygen. Attention is also given to the danger of asphyxiation posed by the growing use of inert gases.

Webster, T.

1982-05-01

160

Optimization of Cryogenic Air Separation Distillation Columns  

Microsoft Academic Search

Cryogenic air separation distillation columns are widely used in industry, which consume a large energy and need to produce a huge amount of need of nitrogen, oxygen and argon products with high purity. Of pervious optimal researches on cryogenic distillation column, few considers argon column due to the complex degree of process. In this work, rigorous optimization model of cryogenic

Yu Zhu; Xinggao Liu; Zhiyong Zhou

2006-01-01

161

Cryogenics and the human exploration of Mars  

Microsoft Academic Search

Current studies within NASA involve extending the human exploration of space from low earth orbit into the solar system, with the first human exploration of Mars proposed in 2014. The key cryogenic technology areas to be addressed in human Mars missions are long-term propellant storage, cryogenic refrigeration, cryogenic liquefaction, and zero gravity fluid management. Passive technologies such as advanced multilayer

L. J. Salerno; P. Kittel

1999-01-01

162

Gauging Systems Monitor Cryogenic Liquids  

NASA Technical Reports Server (NTRS)

Rocket fuel needs to stay cool - super cool, in fact. The ability to store gas propellants like liquid hydrogen and oxygen at cryogenic temperatures (below -243 F) is crucial for space missions in order to reduce their volumes and allow their storage in smaller (and therefore, less costly) tanks. The Agency has used these cryogenic fluids for vehicle propellants, reactants, and life support systems since 1962 with the Centaur upper stage rocket, which was powered with liquid oxygen and liquid hydrogen. During proposed long-duration missions, super-cooled fluids will also be used in space power systems, spaceports, and lunar habitation systems. In the next generation of launch vehicles, gaseous propellants will be cooled to and stored for extended periods at even colder temperatures than currently employed via a process called densification. Densification sub-cools liquids to temperatures even closer to absolute zero (-459 F), increasing the fluid s density and shrinking its volume beyond common cryogenics. Sub-cooling cryogenic liquid hydrogen, for instance, from 20 K (-423 F) to 15 K (-432.4 F) reduces its mass by 10 percent. These densified liquid gases can provide more cost savings from reduced payload volume. In order to benefit from this cost savings, the Agency is working with private industry to prevent evaporation, leakage, and other inadvertent loss of liquids and gases in payloads - requiring new cryogenic systems to prevent 98 percent (or more) of boil-off loss. Boil-off occurs when cryogenic or densified liquids evaporate, and is a concern during launch pad holds. Accurate sensing of propellants aboard space vehicles is also critical for proper engine shutdown and re-ignition after launch, and zero boil-off fuel systems are also in development for the Altair lunar lander.

2009-01-01

163

Programmable 2-D Addressable Cryogenic Aperture Masks  

NASA Technical Reports Server (NTRS)

We are developing a two-dimensional array of square microshutters (programmable aperture mask) for a multi-object spectrometer for the James Webb Space Telescope (JWST). This device will provide random access selection of the areas in the field to be studied. The device is in essence a close packed array of square slits, each of which can be opened independently to select areas of the sky for detailed study.The device is produced using a 100-micron thick silicon wafer as a substrate with 0.5-micron thick silicon nitride shutters on top of it. Silicon nitride has been selected as the blade and flexure material because its stiffness allows thinner and lighter structures than single crystal Si, the chief alternative, and because of its ease of manufacture. The 100 micron silicon wafer is backetched in a high aspect ratio Deep Reactive Ion Etching (Deep RIE) to leave only a support grid for the shutters and the address electronics. The shutter actuation is done magnetically whereas addressing is electrostatic. 128x128 format microshutter arrays have been produced. Their operation has been demostarted on 32x32 subarrays. Good reliability of the fabrication process and good quality of the microshutters has been achieved. The mechanical behavior and optical performance of the fabricated arrays at cryogenic temperature are being studied.

Kutyrev, A. S.; Moseley, S. H.; Jhabvala, M.; Li, M.; Schwinger, D. S.; Silverberg, R. F.; Wesenberg, R. P.

2004-01-01

164

Variable path cryogenic acoustic interferometer  

NASA Astrophysics Data System (ADS)

We describe a variable path acoustic interferometer for use at cryogenic temperatures. Movement is enabled without mechanical coupling via two piezoelectric bimorphs wired and mounted in a manner that preserves the parallelism of two ultrasonic transducers that define the acoustic path. A certain degree of in situ alignment can also be accomplished. Path length sweeps from 0 to 180 ?m have been made at cryogenic temperatures and preliminary sound velocity measurements in liquid 4He and gaseous 3He near 4 K are presented which agree well with past measurements.

Kucera, D. M.; Ketterson, J. B.

1998-12-01

165

Cryogenic thermal diode heat pipes  

NASA Technical Reports Server (NTRS)

The development of spiral artery cryogenic thermal diode heat pipes was continued. Ethane was the working fluid and stainless steel the heat pipe material in all cases. The major tasks included: (1) building a liquid blockage (blocking orifice) thermal diode suitable for the HEPP space flight experiment; (2) building a liquid trap thermal diode engineering model; (3) retesting the original liquid blockage engineering model, and (4) investigating the startup dynamics of artery cryogenic thermal diodes. An experimental investigation was also conducted into the wetting characteristics of ethane/stainless steel systems using a specially constructed chamber that permitted in situ observations.

Alario, J.

1979-01-01

166

Optical Cryogenic Tank Level Sensor  

NASA Technical Reports Server (NTRS)

Cryogenic fluids play an important role in space transportation. Liquid oxygen and hydrogen are vital fuel components for liquid rocket engines. It is also difficult to accurately measure the liquid level in the cryogenic tanks containing the liquids. The current methods use thermocouple rakes, floats, or sonic meters to measure tank level. Thermocouples have problems examining the boundary between the boiling liquid and the gas inside the tanks. They are also slow to respond to temperature changes. Sonic meters need to be mounted inside the tank, but still above the liquid level. This causes problems for full tanks, or tanks that are being rotated to lie on their side.

Duffell, Amanda

2005-01-01

167

Status Of Sorption Cryogenic Refrigeration  

NASA Technical Reports Server (NTRS)

Report reviews sorption refrigeration. Developed for cooling infrared detectors, cryogenic research, and other advanced applications, sorption refrigerators have few moving parts, little vibration, and lifetimes of 10 years or more. Describes types of sorption stages, multistage and hybrid refrigeration systems, power requirements, cooling capacities, and advantages and disadvantages of various stages and systems.

Jones, Jack A.

1988-01-01

168

Ilc Cryogenic Systems Reference Design  

NASA Astrophysics Data System (ADS)

A Global Design Effort (GDE) began in 2005 to study a TeV scale electron-positron linear accelerator based on superconducting radio-frequency (RF) technology, called the International Linear Collider (ILC). In early 2007, the design effort culminated in a reference design for the ILC, closely based on the earlier TESLA design. The ILC will consist of two 250 GeV linacs, which provide positron-electron collisions for high energy physics research. The particle beams will be accelerated to their final energy in superconducting niobium RF cavities operating at 2 kelvin. At a length of about 12 km each, the main linacs will be the largest cryogenic systems in the ILC. Positron and electron sources, damping rings, and beam delivery systems will also have a large number and variety of other superconducting RF cavities and magnets, which require cooling at liquid helium temperatures. Ten large cryogenic plants with 2 kelvin refrigeration are envisioned to cool the main linacs and the electron and positron sources. Three smaller cryogenic plants will cool the damping rings and beam delivery system components predominately at 4.5 K. This paper describes the cryogenic systems concepts for the ILC.

Peterson, T. J.; Geynisman, M.; Klebaner, A.; Parma, V.; Tavian, L.; Theilacker, J.

2008-03-01

169

Fast response cryogen level sensor  

NASA Technical Reports Server (NTRS)

Liquid level in cryogenic tank or pipe, or amount of gas trapped in pipeline flow, is monitored electronically by cylindrical capacitive sensor. Changes in liquid level between concentric tubes of capacitor change its impedance, varying current in drive circuit. Since it is oriented parallel to direction of liquid flow, sensor presents little resistance to moving fluid.

Fitzpatrick, J. B.; Maier, L. C.

1981-01-01

170

CRYOGENIC MACHINING OF KEVLAR COMPOSITES  

Microsoft Academic Search

Previous attempts to machine Kevlar aramid fibre reinforced plastics (KFRP) with conventional cutting tools have proven to be extremely difficult. This has somewhat restricted the material's usage, often negating the advantages of its high strength to weight ratio and fatigue tolerance. The present paper describes a novel technique of machining KFRP under cryogenic conditions with remarkable results compared to those

D. Bhattacharyya; M. N. Allen; S. J. Mander

1993-01-01

171

Operation of large cryogenic systems  

SciTech Connect

This report is based on the past 12 years of experiments on R and D and operation of the 27 kW Fermilab Tevatron Cryogenic System. In general the comments are applicable for all helium plants larger than 1000W (400 l/hr) and non mass-produced nitrogen plants larger than 50 tons per day. 14 refs., 3 figs., 1 tab.

Rode, C.H.; Ferry, B.; Fowler, W.B.; Makara, J.; Peterson, T.; Theilacker, J.; Walker, R.

1985-06-01

172

A new cryogenic diode thermometer  

Microsoft Academic Search

While the introduction of yet another cryogenic diode thermometer is not earth shattering, a new diode thermometer, the DT-600 series, recently introduced by Lake Shore Cryotronics, possesses three features that make it unique among commercial diode thermometers. First, these diodes have been probed at the chip level, allowing for the availability of a bare chip thermometer matching a standard curve-an

S. S. Courts; P. R. Swinehart; C. J. Yeager

2002-01-01

173

A NEW CRYOGENIC DIODE THERMOMETER  

Microsoft Academic Search

While the introduction of yet another cryogenic diode thermometer is not earth shattering, a new diode thermometer, the DT-600 series, recently introduced by Lake Shore Cryotronics, possesses three features that make it unique among commercial diode thermometers. First, these diodes have been probed at the chip level, allowing for the availability of a bare chip thermometer matching a standard curve

S. S. Courts; P. R. Swinehart; C. J. Yeager

174

Background reduction in cryogenic detectors  

SciTech Connect

This paper discusses the background reduction and rejection strategy of the Cryogenic Dark Matter Search (CDMS) experiment. Recent measurements of background levels from CDMS II at Soudan are presented, along with estimates for future improvements in sensitivity expected for a proposed SuperCDMS experiment at SNOLAB.

Bauer, Daniel A.; /Fermilab

2005-04-01

175

A Magnetically Coupled Cryogenic Pump  

NASA Technical Reports Server (NTRS)

Historically, cryogenic pumps used for propellant loading at Kennedy Space Center (KSC) and other NASA Centers have a bellows mechanical seal and oil bath ball bearings, both of which can be problematic and require high maintenance. Because of the extremely low temperatures, the mechanical seals are made of special materials and design, have wearing surfaces, are subject to improper installation, and commonly are a potential leak path. The ball bearings are non-precision bearings [ABEC-1 (Annular Bearing Engineering Council)] and are lubricated using LOX compatible oil. This oil is compatible with the propellant to prevent explosions, but does not have good lubricating properties. Due to the poor lubricity, it has been a goal of the KSC cryogenics community for the last 15 years to develop a magnetically coupled pump, which would eliminate these two potential issues. A number of projects have been attempted, but none of the pumps was a success. An off-the-shelf magnetically coupled pump (typically used with corrosive fluids) was procured that has been used for hypergolic service at KSC. The KSC Cryogenics Test Lab (CTL) operated the pump in cryogenic LN2 as received to determine a baseline for modifications required. The pump bushing, bearings, and thrust rings failed, and the pump would not flow liquid (this is a typical failure mode that was experienced in the previous attempts). Using the knowledge gained over the years designing and building cryogenic pumps, the CTL determined alternative materials that would be suitable for use under the pump design conditions. The CTL procured alternative materials for the bearings (bronze, aluminum bronze, and glass filled PTFE) and machined new bearing bushings, sleeves, and thrust rings. The designed clearances among the bushings, sleeves, thrust rings, case, and case cover were altered once again using experience gained from previous cryogenic pump rebuilds and designs. The alternative material parts were assembled into the pump, and the pump was successfully operated meeting all expected operating parameters. Unique pump sub-assembly parts were designed and manufactured by the CTL using specialized materials determined to be superior for cryogenic thermal applications under the pump design conditions. This work is a proof-of-concept/proof-of-operation of the pump only. Other known internal design modifications to the pump should be accomplished for the long-term use of the pump. An upscaled version of this pump, which is under development and testing at the CTL, can be used either for current or future vehicle loading or for vehicle replenishment. Scaling of this pump can be easily accomplished.

Hatfield, Walter; Jumper, Kevin

2011-01-01

176

Flight data for the Cryogenic Heat Pipe (CRYOHP) Experiment  

NASA Technical Reports Server (NTRS)

This paper presents the flight test results and data correlation for the Cryogenic Heat Pipe Flight Experiment (CRYOHP). CRYOHP is a Hitchhiker Canister experiment that was flown aboard the shuttle Discovery (STS-53) in December of 1992. Two different axially grooved oxygen heat pipes were tested to determine their startup behavior and transport capability in micro-gravity. Three startup cycles were conducted with each heat pipe and transport data was obtained over the range of 60 K to 140 K. Startup in flight was repeatable but slower than observed in ground tests. The transport data shows good agreement with the theoretical model. The CRYOHP test bed, which incorporates five Stifling cycle refrigerators to provide the cryo-cooling, performed as predicted and offers a good micro-gravity test bed for cryogenic thermal devices.

Brennan, Patrick J.; Thienel, Lee; Swanson, Ted; Morgan, Michael

1993-01-01

177

Microwave properties of Yttrium Vanadate at cryogenic temperatures  

E-print Network

Yttrium Vanadate (YVO4) is a birefringent crystal material used in optical isolators and circulators with potentials for application in cryogenic microwave devices. As microwave properties of the YVO4 are not known, we measured the complex permittivity at the frequency of 25 GHz, using the Hakki-Coleman dielectric resonator technique in the temperature range from 13 K to 80 K. The real part of relative permittivity of YVO4 turned out to be similar to that of Sapphire - one of popular dielectric materials, used at microwave frequencies. The measured loss tangent tang {\\delta} of the YVO4 was of the order of 10^(-6) at cryogenic temperatures. As Yttrium Vanadate (YVO4) is easy to synthesis and machine, it may replace the expensive Sapphire in some microwave applications.

Jacob, Mohan V; Krupka, Jerzy; Ledenyov, Dimitri O; Takeuchi, Seiichi

2012-01-01

178

Cryogenic Electronics Being Developed for Space Operation  

NASA Technical Reports Server (NTRS)

Planetary exploration missions and deep space probes require electrical power management and control systems that can operate efficiently and reliably in very low temperature environments. Presently, spacecraft operating in the cold environment of deep space carry a large number of radioisotope heating units to maintain the surrounding temperature of the onboard electronics at approximately 20 C. Electronics capable of operation at cryogenic temperatures would not only tolerate the hostile environment of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures. Thereby, such electronics would reduce system development as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results because semiconductor and dielectric materials have better behavior and tolerance in their electrical and thermal properties at low temperatures. The Low Temperature Electronics Program at the NASA Glenn Research Center is focusing on the research and development of electrical components, circuits, and systems suitable for applications in the aerospace environment and in deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial off-the-shelf as well as developed components that are being characterized include semiconductor switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, dc-dc converters, operational amplifiers, and oscillators are also being investigated for potential use in low-temperature applications. For example, the output response of an advanced oscillator at room temperature and at -190 C is shown. Most oscillators can operate at temperatures down to only -55 C. It can be seen that, for this oscillator, the low temperature of -196 C changed the leading and trailing edges of the oscillator pulses by producing overshoot. The research and development efforts performed under the Low Temperature Electronics Program at Glenn are being carried out through collaboration with other Government agencies, industrial and aerospace companies, and academia. The program supports missions as well as technology development efforts at NASA's Goddard Space Flight Center and Langley Research Center, and the Jet Propulsion Laboratory.

Patterson, Richard L.; Hammoud, Ahmad; Gerber, Scott S.

2002-01-01

179

Feasibility study for a Cryogenic On-Orbit Liquid Depot-Storage, Acquisition and Transfer (COLD-SAT) satellite  

NASA Technical Reports Server (NTRS)

This feasibility study presents the conceptual design of a spacecraft for performing a series of cryogenic fluid management flight experiments. This spacecraft, the Cryogenic On-Orbit Liquid Depot-Storage, Acquisition, and Transfer (COLD-SAT) satellite, will use liquid hydrogen as the test fluid, be launched on a Delta expendable launch vehicle, and conduct a series of experiments over a two to three month period. These experiments will investigate the physics of subcritical cryogens in the low gravity space environment to characterize their behavior and to correlate the data with analytical and numerical models of in-space cryogenic fluid management systems. Primary technologies addressed by COLD-SAT are: (1) pressure control; (2) chilldown; (3) no-vent fill; (4) liquid acquisition device fill; (5) pressurization; (6) low-g fill and drain; (7) liquid acquisition device expulsion; (8) line chilldown; (9) thermodynamic state control; and (10) fluid dumping.

Rybak, S. C.; Willen, G. S.; Follett, W. H.; Hanna, G. J.; Cady, E. C.; Distefano, E.; Meserole, J. S.

1990-01-01

180

Cryogenic switched MOSFET characterization  

NASA Technical Reports Server (NTRS)

Both p channel and n channel enhancement mode MOSFETs can be readily switched on and off at temperatures as low as 2.8 K so that switch sampled readout of a VLWIR Ge:Ga focal plane is electronically possible. Noise levels as low as 100 rms electrons per sample (independent of sample rate) can be achieved using existing p channel MOSFETs, at overall rates up to 30,000 samples/second per multiplexed channel (e.g., 32 detectors at a rate of almost 1,000 frames/second). Run of the mill devices, including very low power dissipation n channel FETs would still permit noise levels of the order of 500 electrons/sample.

1981-01-01

181

Proposal for a cryogenic magnetic field measurement system for SSC dipole magnets  

SciTech Connect

This proposal describes the research and development required, and the subsequent fabrication of, a system capable of making integrated magnetic multipole measurements of cryogenic 40-mm-bore SSC dipole magnets utilizing a cryogenic probe. Our experience and some preliminary studies indicate that it is highly unlikely that a 16-meter-long probe can be fabricated that will have a twist below several milliradians at cryogenic temperatures. We would anticipate a twist of several milliradians just as a result of cooldown stresses. Consequently, this proposal describes a segmented 16-meter-long probe, for which we intend to calibrate the phase of each segment to within 0.1 milliradians. The data for all segments will be acquired simultaneously, and integrated data will be generated from the vector sums of the individual segments. The calibration techniques and instrumentation required to implement this system will be described. The duration of an integral measurement at one current is expected to be under 10 seconds. The system is based on an extrapolation of the techniques used at LBL to measure cryogenic 1-meter models of SSC magnets with a cryogenic probe. It should be noted that the expansion of the dipole bore from 40 to 50 mm may make a warm-finger device practical at a cost of approximately one quarter of the cryogenic probe. A warm quadrupole measurement system can be based upon the same principles. 5 refs., 9 figs., 1 tab.

Green, M.I.; Hansen, L.

1991-03-01

182

Relaxation phenomena in cryogenic electrolytes  

NASA Astrophysics Data System (ADS)

Proposed is a scenario for the development of observed relaxation phenomena in a cryogenic electrolyte with the structure of "liquid hydrogen + injected ions." Ions of one sign are generated in the bulk of liquid hydrogen in the presence of external field E? by a stationary radioactive source of ± ions at the bottom of a vessel. After accumulation near the free surface of the liquid with a finite density ns the ions can break its stability producing a pulse of ion current to the collector located above the liquid surface. The outlined process is periodically repeated. Its period contains information on the ion mobility and, which is most interesting, on dissociation (association) processes occurring in a system of charged particles placed in an external field. The cryogenic problem is a good model for dissociation in the presence of external field occurring in normal electrolytes without any external ion sources.

Shikin, V.; Chikina, I.; Nazin, S.

2013-06-01

183

Cryogenics for the superconducting module test facility  

SciTech Connect

A group of laboratories and universities, with Fermilab taking the lead, are constructing a superconducting cryomodule test facility (SMTF) in the Meson Detector Building (MDB) area at Fermilab. The facility will be used for testing and validating designs for both pulsed and CW systems. A multi phase approach is taken to construct the facility. For the initial phase of the project, cryogens for a single cavity cryomodule will be supplied from the existing Cryogenic Test Facility (CTF) that houses three Tevatron satellite refrigerators. The cooling capacity available for cryomodule testing at MDB results from the liquefaction capacity of the CTF cryogenic system. A cryogenic distribution system to supply cryogens from CTF to MDB is under construction. This paper describes plans, status and challenges of the initial phase of the SMTF cryogenic system.

Klebaner, A.L.; Theilacker, J.C.; /Fermilab

2006-01-01

184

Insulating Cryogenic Pipes With Frost  

NASA Technical Reports Server (NTRS)

Crystallized water vapor fills voids in pipe insulation. Small, carefully controlled amount of water vapor introduced into dry nitrogen gas before it enters aft fuselage. Vapor freezes on pipes, filling cracks in insulation. Ice prevents gaseous nitrogen from condensing on pipes and dripping on structure, in addition to helping to insulate all parts. Industrial applications include large refrigeration plants or facilities that use cryogenic liquids.

Stephenson, J. G.; Bova, J. A.

1985-01-01

185

Cryogenic moderator simulations : confronting reality.  

SciTech Connect

The Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory is a spallation neutron source dedicated to materials research. Its three cryogenic methane moderators provide twelve neutron beams to fourteen instruments and test facilities. This report concerns ongoing activities for benchmarking our Monte Carlo model of the IPNS neutron generation system. This paper concentrates on the techniques (both experimental and calculational) used in such benchmarking activities.

Iverson, E. B.

1999-01-06

186

Shuttle cryogenic supply system optimization study. Volume 4: Cryogenic cooling in environmental control systems  

NASA Technical Reports Server (NTRS)

An analysis of cryogenic fluid cooling in the environmental control system of the space shuttle was conducted. The technique for treating the cryogenic fluid storage and supply tanks and subsystems as integrated systems was developed. It was concluded that a basic incompatibility exists between the heat generated and the cryogen usage rate and cryogens cannot be used to absorb the generated heat. The use of radiators and accumulators to provide additional cooling capability is recommended.

1973-01-01

187

ZERODUR TAILORED for cryogenic application  

NASA Astrophysics Data System (ADS)

ZERODUR® glass ceramic from SCHOTT is known for its very low thermal expansion coefficient (CTE) at room temperature and its excellent CTE homogeneity. It is widely used for ground-based astronomical mirrors but also for satellite applications. Many reference application demonstrate the excellent and long lasting performance of ZERODUR® components in orbit. For space application a low CTE of the mirror material is required at cryogenic temperatures together with a good match of the thermal expansion to the supporting structure material. It is possible to optimize the coefficient of thermal expansion of ZERODUR® for cryogenic applications. This paper reports on measurements of thermal expansion of ZERODUR® down to cryogenic temperatures of 10 K performed by the PTB (Physikalisch Technische Bundesanstallt, Braunschweig, Germany, the national metrology laboratory). The ZERODUR® TAILORED CRYO presented in this paper has a very low coefficient of thermal expansion down to 70 K. The maximum absolute integrated thermal expansion down to 10 K is only about 20 ppm. Mirror blanks made from ZERODUR® TAILORED CRYO can be light weighted to almost 90% with our modern processing technologies. With ZERODUR® TAILORED CRYO, SCHOTT offers the mirror blank material for the next generation of space telescope applications.

Jedamzik, R.; Westerhoff, T.

2014-07-01

188

Cryogenic fluid management in space  

NASA Technical Reports Server (NTRS)

Many future space based vehicles and satellites will require on orbit refuelling procedures. Cryogenic fluid management technology is being developed to assess the requirements of such procedures as well as to aid in the design and development of these vehicles. Cryogenic fluid management technology for this application could be divided into two areas of study, one is concerned with fluid transfer process and the other with cryogenic liquid storage. This division is based upon the needed technology for the development of each area. In the first, the interaction of fluid dynamics with thermodynamics is essential, while in the second only thermodynamic analyses are sufficient to define the problem. The following specific process related to the liquid transfer area are discussed: tank chilldown and fill; tank pressurization; liquid positioning; and slosh dynamics and control. These specific issues are discussed in relation with the required technology for their development in the low gravity application area. In each process the relevant physics controlling the technology is identified and methods for resolving some of the basic questions are discussed.

Antar, Basil N.

1988-01-01

189

Cryogenic actuator for subnanometer positioning  

NASA Astrophysics Data System (ADS)

This paper discusses the development, realization, and qualification of a positioning actuator concept specifically for cryogenic environments. Originally developed for quantum physics research, the actuator also has many applications in astronomic cryogenic instruments to position optical elements with nanometer level accuracy and stability. Typical applications include the correction of thermally induced position errors of optical components after cooling down from ambient to cryogenic temperatures or sample positioning in microscopes. The actuator is nicknamed the ‘PiezoKnob’ because it is piezo based and it is compatible with the typical manipulator knob often found in standard systems for optical benches, such as linear stages or tip/tilt lens holders. Actuation with high stiffness piezo elements enables the Piezoknob to deliver forces up to 50 Newton which allows relatively stiff guiding mechanisms or large pre-loads. The PiezoKnob has been qualified at 77 Kelvin and was shown to work down to 2 Kelvin. As part of the qualification program, the custom developed driving electronics and set point profile have been fine-tuned, by combing measurements with predictions from a dynamic model, thus maximizing efficiency and minimizing power dissipation. Furthermore, the actuator holds its position without power and thanks to its mechanical layout it is absolutely insensitive to drift of the piezo elements or the driving electronics.

Bree, B. v.; Janssen, H.; Paalvast, S.; Albers, R.

2012-09-01

190

Properties of cryogenically worked metals. [stainless steels  

NASA Technical Reports Server (NTRS)

A program was conducted to determine whether the mechanical properties of cryogenically worked 17-7PH stainless steel are suitable for service from ambient to cryogenic temperatures. It was determined that the stress corrosion resistance of the cryo-worked material is quite adequate for structural service. The tensile properties and fracture toughness at room temperature were comparable to titanium alloy 6Al-4V. However, at cryogenic temperatures, the properties were not sufficient to recommend consideration for structural service.

Schwartzberg, F. R.; Kiefer, T. F.

1975-01-01

191

Investigation of cryogenic rupture disc design  

NASA Technical Reports Server (NTRS)

Rupture disc designs of both the active (command actuated) and passive (pressure ruptured) types were evaluated for performance characteristics at cryogenic temperatures and for capability to operate in a variety of cryogens, including gaseous and liquid fluorine. The test results, coupled with information from literature and industry searches, were used to establish a statement of design criteria and recommended practices for application of rupture discs to cryogenic rocket propellant feed and vent systems.

Keough, J. B.; Oldland, A. H.

1973-01-01

192

The evolution of cryogenic safety at Fermilab  

SciTech Connect

Over the past twenty-five years, Fermilab has been involved in cryogenic technology as it relates to pursuing experimentation in high energy physics. The Laboratory has instituted a strong cryogenic safety program and has maintained a very positive safety record. The solid commitment of management and the cryogenic community to incorporating safety into the system life cycle has led to policies that set requirements and help establish consistency for the purchase and installation of equipment and the safety analysis and documentation.

Stanek, R.; Kilmer, J.

1992-12-01

193

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Cryogenic liquids in tank cars. 173.319 Section 173.319 Transportation...Packaging § 173.319 Cryogenic liquids in tank cars. (a) General requirements. (1) A tank car containing a flammable cryogenic liquid...

2013-10-01

194

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Cryogenic liquids in tank cars. 173.319 Section 173.319 Transportation...Packaging § 173.319 Cryogenic liquids in tank cars. (a) General requirements. (1) A tank car containing a flammable cryogenic liquid...

2011-10-01

195

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Cryogenic liquids in tank cars. 173.319 Section 173.319 Transportation...Packaging § 173.319 Cryogenic liquids in tank cars. (a) General requirements. (1) A tank car containing a flammable cryogenic liquid...

2014-10-01

196

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Cryogenic liquids in tank cars. 173.319 Section 173.319 Transportation...Packaging § 173.319 Cryogenic liquids in tank cars. (a) General requirements. (1) A tank car containing a flammable cryogenic liquid...

2010-10-01

197

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Cryogenic liquids in tank cars. 173.319 Section 173.319 Transportation...Packaging § 173.319 Cryogenic liquids in tank cars. (a) General requirements. (1) A tank car containing a flammable cryogenic liquid...

2012-10-01

198

Dynamics of cryogen deposition relative to heat extraction rate during cryogen spray cooling  

Microsoft Academic Search

Goal is to investigate how delivery nozzle design influences the cooling rate of cryogen spray as used in skin laser treatments. Cryogen was sprayed through nozzles that consist of metal tubes with either a narrow or wide diameter and two different lengths. Fast-flashlamp photography showed that the wide nozzles, in particular the long wide one, produced a cryogen jet (very

Wim Verkruysse; Boris Majaron; Guillermo Aguilar; Lars O. Svaasand; J. Stuart Nelson

2000-01-01

199

A new capsule platinum resistance thermometer for cryogenic use  

NASA Astrophysics Data System (ADS)

Standards grade platinum resistance thermometers (SPRTs) obtain their high stability in part due to the strain-free mounting of the sensing wire. The space required for this strain-free mounting normally results in thermometers on the order of 6 mm diameter by 40 mm length in size. While these SPRTs are acceptable in many applications, it is desirable to reduce the size as much as possible for cryogenic use where space is of major concern. For over 40 years Minco Products, Inc. provided a smaller alternative with their model S1059, a high-stability cryogenic capsule platinum resistance thermometer (PRT) packaged in a copper canister sized only 3.2 mm diameter by 9.7 mm length. The packaging was compatible for use over the 13 K to 533 K temperature range. Unfortunately, this product was discontinued in 2009. In its absence, Lake Shore Cryotronics, Inc., has worked with Advanced Sensing Products to develop a similarly sized replacement sensor for cryogenic use. The replacement capsule PRT is manufactured using the model S1059 design, but with modifications to reduce the chance of lead breakage at the epoxy-lead interface. Test devices have been fabricated and tested for temperature response and stability upon repeated calibration from 13 K to 330 K. The new sensor design features and performance data are presented in this work.

Courts, S. S.; Krause, J. K.

2013-09-01

200

Effects of electrostatic discharge on three cryogenic temperature sensor models  

NASA Astrophysics Data System (ADS)

Cryogenic temperature sensors are not usually thought of as electrostatic discharge (ESD) sensitive devices. However, the most common cryogenic thermometers in use today are thermally sensitive diodes or resistors - both electronic devices in their base form. As such, they are sensitive to ESD at some level above which either catastrophic or latent damage can occur. Instituting an ESD program for safe handling and installation of the sensor is costly and it is desirable to balance the risk of ESD damage against this cost. However, this risk cannot be evaluated without specific knowledge of the ESD vulnerability of the devices in question. This work examines three types of cryogenic temperature sensors for ESD sensitivity - silicon diodes, Cernox{trade mark, serif} resistors, and wire wound platinum resistors, all manufactured by Lake Shore Cryotronics, Inc. Testing was performed per TIA/EIA FOTP129 (Human Body Model). Damage was found to occur in the silicon diode sensors at discharge levels of 1,500 V. For Cernox{trade mark, serif} temperature sensors, damage was observed at 3,500 V. The platinum temperature sensors were not damaged by ESD exposure levels of 9,900 V. At the lower damage limit, both the silicon diode and the Cernox{trade mark, serif} temperature sensors showed relatively small calibration shifts of 1 to 3 K at room temperature. The diode sensors were stable with time and thermal cycling, but the long term stability of the Cernox{trade mark, serif} sensors was degraded. Catastrophic failure occurred at higher levels of ESD exposure.

Courts, S. Scott; Mott, Thomas B.

2014-01-01

201

Effects of electrostatic discharge on three cryogenic temperature sensor models  

SciTech Connect

Cryogenic temperature sensors are not usually thought of as electrostatic discharge (ESD) sensitive devices. However, the most common cryogenic thermometers in use today are thermally sensitive diodes or resistors - both electronic devices in their base form. As such, they are sensitive to ESD at some level above which either catastrophic or latent damage can occur. Instituting an ESD program for safe handling and installation of the sensor is costly and it is desirable to balance the risk of ESD damage against this cost. However, this risk cannot be evaluated without specific knowledge of the ESD vulnerability of the devices in question. This work examines three types of cryogenic temperature sensors for ESD sensitivity - silicon diodes, Cernox(trade mark, serif) resistors, and wire wound platinum resistors, all manufactured by Lake Shore Cryotronics, Inc. Testing was performed per TIA/EIA FOTP129 (Human Body Model). Damage was found to occur in the silicon diode sensors at discharge levels of 1,500 V. For Cernox(trade mark, serif) temperature sensors, damage was observed at 3,500 V. The platinum temperature sensors were not damaged by ESD exposure levels of 9,900 V. At the lower damage limit, both the silicon diode and the Cernox(trade mark, serif) temperature sensors showed relatively small calibration shifts of 1 to 3 K at room temperature. The diode sensors were stable with time and thermal cycling, but the long term stability of the Cernox(trade mark, serif) sensors was degraded. Catastrophic failure occurred at higher levels of ESD exposure.

Courts, S. Scott; Mott, Thomas B. [Lake Shore Cryotronics, 575 McCorkle Blvd., Westerville, OH 43082 (United States)

2014-01-29

202

Developing Low-Noise GaAs JFETs For Cryogenic Operation  

NASA Technical Reports Server (NTRS)

Report discusses aspects of effort to develop low-noise, low-gate-leakage gallium arsenide-based junction field-effect transistors (JFETs) for operation at temperature of about 4 K as readout amplifiers and multiplexing devices for infrared-imaging devices. Transistors needed to replace silicon transistors, relatively noisy at 4 K. Report briefly discusses basic physical principles of JFETs and describes continuing process of optimization of designs of GaAs JFETs for cryogenic operation.

Cunningham, Thomas J.

1995-01-01

203

Multi-Channel Electronically Scanned Cryogenic Pressure Sensor And Method For Making Same  

NASA Technical Reports Server (NTRS)

A miniature, multi-channel, electronically scanned pressure measuring device uses electrostatically bonded silicon dies in a multi-element array. These dies are bonded at specific sites on a glass, pre-patterned substrate. Thermal data is multiplexed and recorded on each individual pressure measuring diaphragm. The device functions in a cryogenic environment without the need of heaters to keep the sensor at constant temperatures.

Chapman, John J. (Inventor); Hopson, Purnell, Jr. (Inventor); Holloway, Nancy M. (Inventor)

2001-01-01

204

Shutter mechanism for calibration of the cryogenic diffused infrared background experiment (DIRBE) instrument  

NASA Technical Reports Server (NTRS)

The design requirements, the design, the assembly and alignment, and the test program for a shutter mechanism which must operate at cryogenic temperature and draw less than 1.0 milliwatt are discussed. The design solution to meet these requirements is a device that positions a mirror with repeated accuracy, has no wearing surfaces, and operates at 2.0 K. The unique feature of this device is the simplicity of the mechanism, thus obtaining high reliability.

Tyler, Allen

1986-01-01

205

Charged Probes, Bourdon Tubes Maintain Cryogenic Liquid Level  

NASA Technical Reports Server (NTRS)

The problem: To design a system that automatically maintains the fluid level in a liquid nitrogen cold trap. It is frequently necessary to operate a vacuum system using one or more cold traps for a prolonged period with the cold trap liquid level maintained between set limits. Electronic devices have been subject to failure due to the effect on components of cryogenic temperatures. The solution: An automatic liquid nitrogen dispensing system that uses gas filled probes, driving Bourdon tube gauges equipped with microswitches that, through a relay, control a solenoid valve in the liquid nitrogen storage line.

Krejsa, Mylo J.

1966-01-01

206

Cryogenic method for measuring nuclides and fission gases  

DOEpatents

A cryogenic method is provided for determining airborne gases and particulates from which gamma rays are emitted. A special dewar counting vessel is filled with the contents of the sampling flask which is immersed in liquid nitrogen. A vertically placed sodium-iodide or germanium-lithium gamma-ray detector is used. The device and method are of particular use in measuring and identifying the radioactive noble gases including emissions from coal-fired power plants, as well as fission gases released or escaping from nuclear power plants.

Perdue, P.T.; Haywood, F.F.

1980-05-02

207

Cryogenic filter wheel design for an infrared instrument  

NASA Astrophysics Data System (ADS)

In the last two decades, Spain has built up a strong IR community which has successfully contributed to space instruments, reaching Co-PI level in the SPICA mission (Space Infrared Telescope for Cosmology and Astrophysics). Under the SPICA mission, INTA, focused on the SAFARI instrument requirements but highly adaptable to other missions has designed a cryogenic low dissipation filter wheel with six positions, taking as starting point the past experience of the team with the OSIRIS instrument (ROSETTA mission) filter wheels and adapting the design to work at cryogenic temperatures. One of the main goals of the mechanism is to use as much as possible commercial components and test them at cryogenic temperature. This paper is focused on the design of the filter wheel, including the material selection for each of the main components of the mechanism, the design of elastic mount for the filter assembly, a positioner device designed to provide positional accuracy and repeatability to the filter, allowing the locking of the position without dissipation. In order to know the position of the wheel on every moment a position sensor based on a Hall sensor was developed. A series of cryogenic tests have been performed in order to validate the material configuration selected, the ball bearing lubrication and the selection of the motor. A stepper motor characterization campaign was performed including heat dissipation measurements. The result is a six position filter wheel highly adaptable to different configurations and motors using commercial components. The mechanism was successfully tested at INTA facilities at 20K at breadboard level.

Azcue, Joaquín.; Villanueva, Carlos; Sánchez, Antonio; Polo, Cristina; Reina, Manuel; Carretero, Angel; Torres, Josefina; Ramos, Gonzalo; Gonzalez, Luis M.; Sabau, Maria D.; Najarro, Francisco; Pintado, Jesús M.

2014-09-01

208

Cryogenic Operation Methodology and Cryogen Management at CERN over the last 15 Years  

E-print Network

CERN, the European Organization for Nuclear Research has progressively implemented and brought into operation an impressive number of cryogenic units (34). The paper will present the evolution of CERN’s cryogenic infrastructure and summarize results from cryogenic operation cumulating 590’000 running hours over the last fifteen years. The implemented methodology allowing reaching a high level of plant reliability will be described. CERN also becomes an intensive user of cryogens. Contracts for the delivery of 320 t of liquid helium and 70’000 t of liquid nitrogen have been adjudicated. The paper will describe the procurement strategy, the storage infrastructure and cryogen inventory.

Delikaris, D; Claudet, S; Gayet, Ph; Passardi, Giorgio; Serio, L; Tavian, L

2009-01-01

209

Study and design of cryogenic propellant acquisition systems. Volume 1: Design studies  

NASA Technical Reports Server (NTRS)

An in-depth study and selection of practical propellant surface tension acquisition system designs for two specific future cryogenic space vehicles, an advanced cryogenic space shuttle auxiliary propulsion system and an advanced space propulsion module is reported. A supporting laboratory scale experimental program was also conducted to provide design information critical to concept finalization and selection. Designs using localized pressure isolated surface tension screen devices were selected for each application and preliminary designs were generated. Based on these designs, large scale acquisition prototype hardware was designed and fabricated to be compatible with available NASA-MSFC feed system hardware.

Burge, G. W.; Blackmon, J. B.

1973-01-01

210

Cryogenic, high speed, turbopump bearing cooling requirements  

NASA Technical Reports Server (NTRS)

Although the Space Shuttle Main Engine (SSME) has repeatedly demonstrated the capability to perform during launch, the High Pressure Oxidizer Turbopump (HPOTP) main shaft bearings have not met their 7.5 hour life requirement. A tester is being employed to provide the capability of subjecting full scale bearings and seals to speeds, loads, propellants, temperatures, and pressures which simulate engine operating conditions. The tester design permits much more elaborate instrumentation and diagnostics than could be accommodated in an SSME turbopump. Tests were made to demonstrate the facilities; and the devices' capabilities, to verify the instruments in its operating environment and to establish a performance baseline for the flight type SSME HPOTP Turbine Bearing design. Bearing performance data from tests are being utilized to generate: (1) a high speed, cryogenic turbopump bearing computer mechanical model, and (2) a much improved, very detailed thermal model to better understand bearing internal operating conditions. Parametric tests were also made to determine the effects of speed, axial loads, coolant flow rate, and surface finish degradation on bearing performance.

Dolan, Fred J.; Gibson, Howard G.; Cannon, James L.; Cody, Joe C.

1988-01-01

211

Cryogenic Cermic Multilayer Capacitors for Power Electronics  

SciTech Connect

Recent advances in the areas of high temperature superconductors and low temperature MOSFET devices have opened the door to the possibility of developing highly efficient low-temperature power electronics. The most commonly used high-efficiency capacitors are based on high dielectric constant (K {approx} 1000-4000) barium titanate doped to yield and X7R temperature dependence ({+-}15% change in capacitance from -55 deg. C to 125 deg. C); however, below their minimum use temperature the capacitance drops-off quickly leading to a low volumetric efficiency and high temperature coefficient of capacitance (TCC) at cryogenic temperatures.A series of low temperature materials with moderate to high dielectric constants have been specifically developed for low temperature operation (below 80K). The capacitors fall into three main categories: low TCC, high volumetric efficiency, and energy storage. In the low TCC category, co-fired multilayer ceramic capacitors (MLCCs) were fabricated with capacitance values up to 62nF at 30K, TCCs from 0.9 to 2% below 80K, and losses on the order of 0.0001. In the high volumetric efficiency category, dielectrics with permittivities ranging from 1,000 to 30,000 were demonstrated.

Alberta, E. F.; Hackenberger, W. S. [TRS Technologies, Inc., 2820 East College Ave., State College, PA, 16803 (United States)

2006-03-31

212

Cryogenic support system for airborne superconducting generators  

Microsoft Academic Search

The paper describes a study underway to evaluate techniques and system designs for providing the cryogenic cooling to support an airborne superconducting generator system. Emphasis was placed on minimizing the weight of the airborne system and providing the most cost-effective approach for supplying the cryogenic cooling from the wellhead source to the aircraft. The most cost-effective system is one providing

P. J. Kerney; P. A. Lessard

1980-01-01

213

Cryogenic Boil-Off Reduction System Testing  

NASA Technical Reports Server (NTRS)

The Cryogenic Boil-Off Reduction System was tested with LH2 and LOX in a vacuum chamber to simulate space vacuum and the temperatures of low Earth orbit. Testing was successful and results validated the scaling study model that predicts active cooling reduces upper stage cryogenic propulsion mass for loiter periods greater than 2 weeks.

Plachta, David W.; Johnson, Wesley L.; Feller, Jeffery

2014-01-01

214

Foam vessel for cryogenic fluid storage  

DOEpatents

Cryogenic storage and separator vessels made of polyolefin foams are disclosed, as are methods of storing and separating cryogenic fluids and fluid mixtures using these vessels. In one embodiment, the polyolefin foams may be cross-linked, closed-cell polyethylene foams with a density of from about 2 pounds per cubic foot to a density of about 4 pounds per cubic foot.

Spear, Jonathan D (San Francisco, CA)

2011-07-05

215

Cryogenic testing of the TPC superconducting solenoid  

Microsoft Academic Search

This report describes the results of a series of tests on the TPC superconducting magnet cryogenic system which occurred during the winter and spring of 1983. The tests occurred at interaction region 2 of the PEP colliding beam facility at the Stanford Linear Accelerator Center (SLAC). The TPC Magnet Cryogenic System which was tested includes the following major components: a

M. A. Green; R. G. Smits; J. D. Taylor; V. Vanslyke; F. Barrera; H. Petersen; C. E. Rago; R. I. Rinta; D. Talaska; R. D. Watt

1983-01-01

216

Cryogenic Microwave Anisotropic Artificial Frank Trang  

E-print Network

Cryogenic Microwave Anisotropic Artificial Materials by Frank Trang B.S., University of California entitled: Cryogenic Microwave Anisotropic Artificial Materials written by Frank Trang has been approved acceptable presentation standards Of scholarly work in the above mentioned discipline. #12;Trang, Frank (Ph

Popovic, Zoya

217

Ethane rejection from existing cryogenic plants  

Microsoft Academic Search

Natural gas cryogenic expander plants are designed for maximum economic ethane recovery. The percentage of ethane recovered depends on various factors, such as temperature, pressure, and composition of the inlet gas; demethanizer tower pressure; type of cryogenic process; and whether supplemental refrigeration is used. Plants now in service typically recover in the range of 70 to 80% ethane. However, with

Schnack

1982-01-01

218

Cryogenic Target Performance on OMEGA  

NASA Astrophysics Data System (ADS)

Ignition-relevant target physics is studied using direct-drive cryogenic D2 and DT implosions on the OMEGA Laser System. These experiments are designed to validate the performance of polar-drive ignition designs for the NIF using energy-scaled symmetric-drive designs on OMEGA. The focus of current experiments is on shell stability and preheat at ignition adiabats. Recent work with cryogenic cone-in-shell targets demonstrated the sensitivity of the baseline design to shock (mis)-timing and subsequent shock-induced preheating. Hot-electron preheat was shown to be mitigated by including high-Z dopants in the ablator that raise the temperature of the corona and increase the threshold for the two-plasmon decay. Nonlocal heat transport was found to be important in modeling laser absorption during the leading picket, and hydrodynamic growth of target modulations was experimentally shown to be stabilized at peak drive intensities by these nonlocal effects. Finally, much work has been done to prepare the cryogenic target systems for backlighting using the new high-energy, short-pulse beams provided by the recently completed OMEGA EP Facility. This work includes proof-of-principle demonstrations using OMEGA beams to backlight a cryogenic core. The status of short-pulse backlighting will be presented along with the latest fuel compression and target-performance results. This work was supported by the U.S. Department of Energy Office of Inertial Confinement Fusion under Cooperative Agreement No. DE-FC52-08NA28302. Contributors: R. Betti, R.S. Craxton, J.A. Delettrez, D.H. Edgell, V.Yu. Glebov, V.N. Goncharov, D.R. Harding, S.X. Hu, J.P. Knauer, F.J. Marshall, R.L. McCrory, P.W. McKenty, D.D. Meyerhofer, P.B. Radha, S.P. Regan, T.C. Sangster, W. Seka, R.W. Short, S. Skupsky, J.M. Soures, C. Stoeckl, B. Yaakobi, UR/LLE; J.A. Frenje, C.K. Li, R.D. Petrasso, F.H. S'eguin, PSFC MIT.

Smalyuk, V. A.

2008-11-01

219

Fiberglass supports for cryogenic tanks  

NASA Technical Reports Server (NTRS)

Analysis, design, fabrication, and test activities were conducted to develop additional technology needed for application of filament-wound fiberglass struts to cryogenic flight tankage. It was conclusively verified that monocoque cylinder or ogive struts are optimum or near-optimum for the range of lengths and loads studied, that a higher strength-to-weight ratio can be achieved for fiberglass struts than for any metallic struts, and that integrally-wrapped metallic end fittings can be used to achieve axial load transfer without reliance on bond strength or mechanical fasteners.

Keller, C. W.

1972-01-01

220

Techniques for on-orbit cryogenic servicing  

NASA Astrophysics Data System (ADS)

NASA (National Aeronautics and Space Administration) has a renewed interest in on-orbit cryogen storage and transfer to support its mission to explore near-earth objects such as asteroids and comets. The Cryogenic Propellant Storage and Transfer Technology Demonstration Mission (CPST-TDM), managed by the NASA Glenn Research Center (GRC) and scheduled for launch in 2018, will demonstrate numerous key technologies applicable to a cryopropellant fuel depot. As an adjunct to the CPST-TDM work, experiments at NASA Goddard Space Flight Center (GSFC) will support the development of techniques to manage and transfer cryogens on-orbit and expand these techniques as they may be applicable to servicing science missions using solid cryogens such as the Wide-field Infrared Survey Explorer (WISE). The results of several ground experiments are described, including autogenous pressurization used for transfer of liquid nitrogen and argon, characterization of the transfer and solidification of argon, and development of robotic tools for cryogen transfer.

DeLee, C. H.; Barfknecht, P.; Breon, S.; Boyle, R.; DiPirro, M.; Francis, J.; Huynh, J.; Li, X.; McGuire, J.; Mustafi, S.; Tuttle, J.; Wegel, D.

2014-11-01

221

Design and Testing of a Cryogenic Capillary Pumped Loop Flight Experiment  

NASA Technical Reports Server (NTRS)

This paper details the flight configuration and pre-flight performance test results of the fifth generation cryogenic capillary pumped loop (CCPL-5). This device will fly on STS-95 in October 1998 as part of the CRYOTSU Flight Experiment. This flight represents the first in-space demonstration of a CCPL, a miniaturized two-phase fluid circulator for thermally linking cryogenic cooling sources to remote cryogenic components. CCPL-5 utilizes N2 as the working fluid and has a practical operating range of 75-110 K. Test results indicate that CCPL-5, which weighs about 200 grams, can transport over 10 W of cooling a distance of 0.25 m (or more) with less than a 5 K temperature drop.

Bugby, David C.; Kroliczek, Edward J.; Ku, Jentung; Swanson, Ted; Tomlinson, B. J.; Davis, Thomas M.; Baumann, Jane; Cullimore, Brent

1998-01-01

222

Alignment-invariant mirror holder for cryogenic environment and its application to GIANO-TNG  

NASA Astrophysics Data System (ADS)

There are many ways to achieve the positioning accuracy established from tolerance in a cryogenic environment. One method is an opto-mechanical design which stays aligned at room temperature and at liquid nitrogen temperature without modifications. This could be achieved using aluminium mirrors with thermally matched aluminium holders and optical bench, that isotropically contract at cryogenic temperatures. The design of holders should allow some adjustment of the optics positions to correct possible errors in the manufacturing of the optical bench and/or optical holders themselves, without precluding the isotropic contraction during the cooling to the working temperature. This work illustrates the last prototype of cryogenic mirror-holder developed in our laboratory. The mirror mounting is based on a set of six forces which pull the mirror against the tree orthogonal faces of a reference corner. Adjustments to the mirror alignment can be achieved by means of six aluminium micrometers. Here we describe the device and illustrate the test results.

Mochi, Iacopo; Baffa, Carlo; Donati, Simone L.; Falcini, Gilberto; Gennari, Sandro; Oliva, Ernesto; Origlia, Livia; Tomelleri, Raffaele

2006-06-01

223

Computer-controlled cryogenic-temperature controller. Final report, September 1982-January 1984  

SciTech Connect

In laboratories which do materials characterization it is necessary to have a temperature controller which can be computer controlled, is accurate to within .1-.2K, can control temperature from 15-350K with a drift of no more than .1, and is relatively unaffected by the presence of a magnetic field on the sample container. The subject controller uses two thermometers to meet these requirements. One is a commercially available calibrated silicon diode manufactured expressly for this type of application. The second thermometer is used for control. Once the sample has reached the setpoint according to the calibrated thermometer the control thermometer's value is sampled and used as the new setpoint. Since the control thermometer should be insensitive to a mag field the sample will remain at the desired temperature when the magnetic field is applied. Cryogenic, Computer control, Magnetic field, Cryogenics, Cryogenic storage devices.

Perrin, R.E.

1990-01-10

224

Nanotomography of labeled cryogenic cells  

NASA Astrophysics Data System (ADS)

By employing the natural absorption contrast of organic matter in water at 0.5 keV photon energy, X-ray microcopy has resolved 30 nm structures in animal cells. To protect the cells from radiation damage caused by x-rays, imaging of the samples was performed at cryogenic temperatures, which makes it possible to take multiple images of a single cell. Due to the small numerical aperture of zone plates, X-ray objectives have a depth of focus on the order of several microns. By treating the X-ray microscopic images as projections of the sample absorption, computed tomography (CT) can be performed. Since cryogenic biological samples are resistant to radiation damage, it is possible to reconstruct frozen-hydrated cells imaged with a full-field X-ray microscope. This approach is used to obtain three- dimensional information about the location of specific proteins in cells. To localize proteins in cells, immunolabelling with strongly X-ray absorbing nanoparticles was performed. With the new tomography apparatus developed for the X-ray microscope XM-1 installed at the ALS, we have performed tomography of immunolabelled frozen-hydrated cells to detect protein distributions in all three dimensions inside of cells. As a first example, the distribution of the nuclear protein, male specific lethal 1 (MSL-1) in the Drosophila melanogaster cell was studied.

Schneider, Gerd; Knoechel, Christian; Vogt, Stefan; Weiss, Daniel; Anderson, Erik H.

2002-01-01

225

Computed Tomography of Cryogenic Cells  

NASA Astrophysics Data System (ADS)

Soft X-ray microscopy has resolved 30 nm structures in biological cells. To protect the cells from radiation damage caused by X-rays, imaging of the samples has to be performed at cryogenic temperatures, which makes it possible to take multiple images of a single cell. Due to the small numerical aperture of zone plates, X-ray objectives have a depth of focus on the order of several microns. By treating the X-ray microscopic images as projections of the sample absorption, computed tomography (CT) can be performed. Since cryogenic biological samples are resistant to radiation damage, it is possible to reconstruct frozen-hydrated cells imaged with a full-field X-ray microscope. This approach is used to obtain three-dimensional information about the location of specific proteins in cells. To localize proteins in cells, immunolabeling with strongly X-ray absorbing nanoparticles was performed. With the new tomography setup developed for the X-ray microscope XM-1 installed at the ALS, we have performed tomography of immunolabeled frozen-hydrated cells to detect protein distributions inside of cells. As a first example, the distribution of the nuclear protein male-specific lethal 1 (MSL-1) in the Drosophila melanogaster cell was studied.

Schneider, G.; Anderson, E.; Vogt, S.; Knöchel, C.; Weiss, D.; Legros, M.; Larabell, C.

226

Simulations of Cavitating Cryogenic Inducers  

NASA Technical Reports Server (NTRS)

Simulations of cavitating turbopump inducers at their design flow rate are presented. Results over a broad range of Nss, numbers extending from single-phase flow conditions through the critical head break down point are discussed. The flow characteristics and performance of a subscale geometry designed for water testing are compared with the fullscale configuration that employs LOX. In particular, thermal depression effects arising from cavitation in cryogenic fluids are identified and their impact on the suction performance of the inducer quantified. The simulations have been performed using the CRUNCH CFD[R] code that has a generalized multi-element unstructured framework suitable for turbomachinery applications. An advanced multi-phase formulation for cryogenic fluids that models temperature depression and real fluid property variations is employed. The formulation has been extensively validated for both liquid nitrogen and liquid hydrogen by simulating the experiments of Hord on hydrofoils; excellent estimates of the leading edge temperature and pressure depression were obtained while the comparisons in the cavity closure region were reasonable.

Dorney, Dan (Technical Monitor); Hosangadi, Ashvin; Ahuja, Vineet; Ungewitter, Ronald J.

2004-01-01

227

Shadowgraphy of transcritical cryogenic fluids  

NASA Technical Reports Server (NTRS)

The future of liquid-rocket propulsion depends heavily on continued development of high pressure liquid oxygen/hydrogen systems that operate near or above the propellant critical states; however, current understanding of transcritical/supercritical injection and combustion is yet lacking. The Phillips Laboratory and the United Technologies Research Center are involved in a collaborative effort to develop diagnostics for and make detailed measurements of transcritical droplet vaporization and combustion. The present shadowgraph study of transcritical cryogenic fluids is aimed at providing insight into the behavior of liquid oxygen or cryogenic stimulants as they are injected into a supercritical environment of the same or other fluids. A detailed history of transcritical injection of liquid nitrogen into gaseous nitrogen at reduced pressures of 0.63 (subcritical) to 1.05 (supercritical) is provided. Also, critical point enhancement due to gas phase solubility and mixture effects is investigated by adding helium to the nitrogen system, which causes a distinct liquid phase to re-appear at supercritical nitrogen pressures. Liquid oxygen injection into supercritical argon or nitrogen, however, does not indicate an increase in the effective critical pressure of the system.

Woodward, R. D.; Talley, D. G.; Anderson, T. J.; Winter, M.

1994-01-01

228

CRYOTE (Cryogenic Orbital Testbed) Concept  

NASA Technical Reports Server (NTRS)

Demonstrating cryo-fluid management (CFM) technologies in space is critical for advances in long duration space missions. Current space-based cryogenic propulsion is viable for hours, not the weeks to years needed by space exploration and space science. CRYogenic Orbital TEstbed (CRYOTE) provides an affordable low-risk environment to demonstrate a broad array of critical CFM technologies that cannot be tested in Earth's gravity. These technologies include system chilldown, transfer, handling, health management, mixing, pressure control, active cooling, and long-term storage. United Launch Alliance is partnering with Innovative Engineering Solutions, the National Aeronautics and Space Administration, and others to develop CRYOTE to fly as an auxiliary payload between the primary payload and the Centaur upper stage on an Atlas V rocket. Because satellites are expensive, the space industry is largely risk averse to incorporating unproven systems or conducting experiments using flight hardware that is supporting a primary mission. To minimize launch risk, the CRYOTE system will only activate after the primary payload is separated from the rocket. Flying the testbed as an auxiliary payload utilizes Evolved Expendable Launch Vehicle performance excess to cost-effectively demonstrate enhanced CFM.

Gravlee, Mari; Kutter, Bernard; Wollen, Mark; Rhys, Noah; Walls, Laurie

2009-01-01

229

Cryogen-free dilution refrigerators  

NASA Astrophysics Data System (ADS)

We review briefly our first cryogen-free dilution refrigerator (CF-DR) which was precooled by a GM cryocooler. We then show how today's dry DRs with pulse tube precooling have developed. A few examples of commercial DRs are explained and noteworthy features pointed out. Thereby we describe the general advantages of cryogen-free DRs, but also show where improvements are still desirable. At present, our dry DR has a base temperature of 10 mK and a cooling capacity of 700 ?W at a mixing chamber temperature of 100 mK. In our cryostat, in most recent work, an additional refrigeration loop was added to the dilution circuit. This 4He circuit has a lowest temperature of about 1 K and a refrigeration capacity of up to 100 mW at temperatures slightly above 1 K; the dilution circuit and the 4He circuit can be run separately or together. The purpose of this additional loop is to increase the cooling capacity for experiments where the cooling power of the still of the DR is not sufficient to cool cold amplifiers and cables, e.g. in studies on superconducting quantum circuits or astrophysical applications.

Uhlig, K.

2012-12-01

230

Power Electronics Being Developed for Deep Space Cryogenic Applications  

NASA Technical Reports Server (NTRS)

Electronic circuits and systems designed for deep space missions need to operate reliably and efficiently in harsh environments that include very low temperatures. Spacecraft that operate in such cold environments carry a large number of heaters so that the ambient temperature for the onboard electronics remains near 20 C. Electronics that can operate at cryogenic temperatures will simplify system design and reduce system size and weight by eliminating the heaters and their associated structures. As a result, system development and launch cost will be reduced. At the NASA Glenn Research Center, an ongoing program is focusing on the development of power electronics geared for deep space low-temperature environments. The research and development efforts include electrical components design, circuit design and construction, and system integration and demonstration at cryogenic temperatures. Investigations are being carried out on circuits and systems that are targeted for use in NASA missions where low temperatures will be encountered: devices such as ceramic and tantalum capacitors, metal film resistors, semiconductor switches, magnetics, and integrated circuits including dc/dc converters, operational amplifiers, voltage references, and motor controllers. Test activities cover a wide range of device and circuit performance under simple as well as complex test conditions, such as multistress and thermal cycling. The effect of low-temperature conditions on the switching characteristics of an advanced silicon-on-insulator field effect transistor is shown. For gate voltages (VGS) below 2.6 V, drain currents at -190 C are lower than drain currents at room temperature (20 C).

Patterson, Richard L.; Hammoud, Ahmad

2003-01-01

231

Experimental measurements and noise analysis of a cryogenic radiometer  

SciTech Connect

A cryogenic radiometer device, intended for use as part of an electrical-substitution radiometer, was measured at low temperature. The device consists of a receiver cavity mechanically and thermally connected to a temperature-controlled stage through a thin-walled polyimide tube which serves as a weak thermal link. With the temperature difference between the receiver and the stage measured in millikelvin and the electrical power measured in picowatts, the measured responsivity was 4700 K/mW and the measured thermal time constant was 14 s at a stage temperature of 1.885 K. Noise analysis in terms of Noise Equivalent Power (NEP) was used to quantify the various fundamental and technical noise contributions, including phonon noise and Johnson-Nyquist noise. The noise analysis clarifies the path toward a cryogenic radiometer with a noise floor limited by fundamental phonon noise, where the magnitude of the phonon NEP is 6.5 fW/?(Hz) for the measured experimental parameters.

Carr, S. M.; Woods, S. I.; Jung, T. M.; Carter, A. C.; Datla, R. U. [National Institute of Standards and Technology (NIST), 100 Bureau Drive, Gaithersburg, Maryland 20899 (United States)

2014-07-15

232

Experimental measurements and noise analysis of a cryogenic radiometer.  

PubMed

A cryogenic radiometer device, intended for use as part of an electrical-substitution radiometer, was measured at low temperature. The device consists of a receiver cavity mechanically and thermally connected to a temperature-controlled stage through a thin-walled polyimide tube which serves as a weak thermal link. With the temperature difference between the receiver and the stage measured in millikelvin and the electrical power measured in picowatts, the measured responsivity was 4700 K/mW and the measured thermal time constant was 14 s at a stage temperature of 1.885 K. Noise analysis in terms of Noise Equivalent Power (NEP) was used to quantify the various fundamental and technical noise contributions, including phonon noise and Johnson-Nyquist noise. The noise analysis clarifies the path toward a cryogenic radiometer with a noise floor limited by fundamental phonon noise, where the magnitude of the phonon NEP is 6.5 fW/?Hz for the measured experimental parameters. PMID:25085171

Carr, S M; Woods, S I; Jung, T M; Carter, A C; Datla, R U

2014-07-01

233

Experimental measurements and noise analysis of a cryogenic radiometer  

NASA Astrophysics Data System (ADS)

A cryogenic radiometer device, intended for use as part of an electrical-substitution radiometer, was measured at low temperature. The device consists of a receiver cavity mechanically and thermally connected to a temperature-controlled stage through a thin-walled polyimide tube which serves as a weak thermal link. With the temperature difference between the receiver and the stage measured in millikelvin and the electrical power measured in picowatts, the measured responsivity was 4700 K/mW and the measured thermal time constant was 14 s at a stage temperature of 1.885 K. Noise analysis in terms of Noise Equivalent Power (NEP) was used to quantify the various fundamental and technical noise contributions, including phonon noise and Johnson-Nyquist noise. The noise analysis clarifies the path toward a cryogenic radiometer with a noise floor limited by fundamental phonon noise, where the magnitude of the phonon NEP is 6.5 {fW}/sqrt{Hz} for the measured experimental parameters.

Carr, S. M.; Woods, S. I.; Jung, T. M.; Carter, A. C.; Datla, R. U.

2014-07-01

234

Cryogenic Control Architecture for Large-Scale Quantum Computing  

NASA Astrophysics Data System (ADS)

Solid-state qubits have recently advanced to the level that enables them, in principle, to be scaled up into fault-tolerant quantum computers. As these physical qubits continue to advance, meeting the challenge of realizing a quantum machine will also require the development of new supporting devices and control architectures with complexity far beyond the systems used in today's few-qubit experiments. Here, we report a microarchitecture for controlling and reading out qubits during the execution of a quantum algorithm such as an error-correcting code. We demonstrate the basic principles of this architecture using a cryogenic switch matrix implemented via high-electron-mobility transistors and a new kind of semiconductor device based on gate-switchable capacitance. The switch matrix is used to route microwave waveforms to qubits under the control of a field-programmable gate array, also operating at cryogenic temperatures. Taken together, these results suggest a viable approach for controlling large-scale quantum systems using semiconductor technology.

Hornibrook, J. M.; Colless, J. I.; Conway Lamb, I. D.; Pauka, S. J.; Lu, H.; Gossard, A. C.; Watson, J. D.; Gardner, G. C.; Fallahi, S.; Manfra, M. J.; Reilly, D. J.

2015-02-01

235

D0 Cryogenic System Superconducting Solenoid Platform I/O  

SciTech Connect

The Dzero detector is scheduled for a major upgrade between 1996 and 1999. This note describes the specifications and configuration of the physical Input/Output devices and instrumentation of the 2 Tesla Superconducting Solenoid. The Solenoid and the VLPC cryostats both reside on the detector platform and are cooled by the Dzero Helium Refrigerator. The cryogenic process control s for these two components will be an extension of the TI565 programmable logic controller system used for other Dzero cryogenic controls. Two Input/Output Bases will be installed on the Dzero detector platform near the cryo corner. These I/O bases will handle all the sensor input and process control output devices from the Solenoid and VLPC cryostats. Having the I/O bases installed on the detector platform makes the connecting cabl ing to the platform much easier . All the instruments are wired directly to the I/O base. The bases have only one communications network cabl e that must be routed off the platform to the South side of the Dzero building.

Markley, D.; /Fermilab

1997-10-09

236

Overview of Air Force Research Laboratory cryogenic technology development programs  

Microsoft Academic Search

This paper presents an overview of the cryogenic refrigerator and cryogenic integration programs in development and characterization under the Cryogenic Technology Group, Space Vehicles Directorate of the Air Force Research Laboratory (AFRL). The vision statement for the group is to support the pace community as the center of excellence for developing and transitioning space cryogenic thermal management technologies. The primary

Thomas M. Davis; B. J. Tomlinson

1998-01-01

237

Vent System Analysis for the Cryogenic Propellant Storage Transfer Ground Test Article  

NASA Technical Reports Server (NTRS)

To test and validate key capabilities and technologies required for future exploration elements such as large cryogenic propulsion stages and propellant depots, NASA is leading the efforts to develop and design the Cryogenic Propellant Storage and Transfer (CPST) Cryogenic Fluid Management (CFM) payload. The primary objectives of CPST payload are to demonstrate: 1) in-space storage of cryogenic propellants for long duration applications; and 2) in-space transfer of cryogenic propellants. The Ground Test Article (GTA) is a technology development version of the CPST payload. The GTA consists of flight-sized and flight-like storage and transfer tanks, liquid acquisition devices, transfer, and pressurization systems with all of the CPST functionality. The GTA is designed to perform integrated passive and active thermal storage and transfer performance testing with liquid hydrogen (LH2) in a vacuum environment. The GTA storage tank is designed to store liquid hydrogen and the transfer tank is designed to be 5% of the storage tank volume. The LH2 transfer subsystem is designed to transfer propellant from one tank to the other utilizing pressure or a pump. The LH2 vent subsystem is designed to prevent over-pressurization of the storage and transfer tanks. An in-house general-purpose computer program was utilized to model and simulate the vent subsystem operation. The modeling, analysis, and the results will be presented in the final paper.

Hedayat, A

2013-01-01

238

Insulation Characteristics of Bushing Shed at Cryogenic Temperature  

NASA Astrophysics Data System (ADS)

In the development of high-Tc superconducting(HTS) devices, the bushing for HTS devices (HTS bushing) is the core technology, the need to because of supply high voltage to the cable or the winding of the transformer. The lower part of the bushing is exposed to the liquid nitrogen (LN2), and it has many sheds. In particular, the insulation body with sheds and electrical insulation at cryogenic temperature have attracted a great deal of interest from the view point of the size, weight and efficiency of bushing. This study has mainly investigated the shed and insulation body by comparing glass fiber reinforced plastics (GFRP) in LN2. We investigated the surface discharge characteristics according to insulating materials, width and height of the shed.

Kim, W. J.; Kim, Y. J.; Kim, S. H.

2014-05-01

239

Hybrid Composite Cryogenic Tank Structure  

NASA Technical Reports Server (NTRS)

A hybrid lightweight composite tank has been created using specially designed materials and manufacturing processes. The tank is produced by using a hybrid structure consisting of at least two reinforced composite material systems. The inner composite layer comprises a distinct fiber and resin matrix suitable for cryogenic use that is a braided-sleeve (and/or a filamentwound layer) aramid fiber preform that is placed on a removable mandrel (outfitted with metallic end fittings) and is infused (vacuum-assisted resin transfer molded) with a polyurethane resin matrix with a high ductility at low temperatures. This inner layer is allowed to cure and is encapsulated with a filamentwound outer composite layer of a distinct fiber resin system. Both inner and outer layer are in intimate contact, and can also be cured at the same time. The outer layer is a material that performs well for low temperature pressure vessels, and it can rely on the inner layer to act as a liner to contain the fluids. The outer layer can be a variety of materials, but the best embodiment may be the use of a continuous tow of carbon fiber (T-1000 carbon, or others), or other high-strength fibers combined with a high ductility epoxy resin matrix, or a polyurethane matrix, which performs well at low temperatures. After curing, the mandrel can be removed from the outer layer. While the hybrid structure is not limited to two particular materials, a preferred version of the tank has been demonstrated on an actual test tank article cycled at high pressures with liquid nitrogen and liquid hydrogen, and the best version is an inner layer of PBO (poly-pphenylenebenzobisoxazole) fibers with a polyurethane matrix and an outer layer of T-1000 carbon with a high elongation epoxy matrix suitable for cryogenic temperatures. A polyurethane matrix has also been used for the outer layer. The construction method is ideal because the fiber and resin of the inner layer has a high strain to failure at cryogenic temperatures, and will not crack or produce leaks. The outer layer serves as more of a high-performance structural unit for the inner layer, and can handle external environments.

DeLay, Thomas

2011-01-01

240

Other cryogenic wind-tunnel projects  

NASA Technical Reports Server (NTRS)

Following the development of the cryogenic wind tunnel at the NASA Langley Research Center in 1972, a large number of cryogenic wind-tunnel projects have been undertaken at various research establishments around the world. Described in this lecture are cryogenic wind-tunnel projects in China (Chinese Aeronautical Research and Development Center), England (College of Aeronautics at Cranfield, Royal Aircraft Establishment - Bedford, and University of Southampton), Japan (National Aerospace Laboratory, University of Tsukuba, and National Defense Academy), Sweden (Rollab), and the United States (Douglas Aircraft Co., University of Illinois at Urbana-Champaign, and NASA Langley).

Kilgore, R. A.

1985-01-01

241

The Nuclear Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progress made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP). Nuclear propulsion can be affordable and viable compared to other propulsion systems and must overcome a biased public fear due to hyper-environmentalism and a false perception of radiation and explosion risk.

Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

2014-01-01

242

A cryogenic infrared calibration target  

NASA Astrophysics Data System (ADS)

A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R ? 0.003, from 800 to 4800 cm-1 (12 - 2 ?m). Upon expanding the spectral range under consideration to 400-10 000 cm-1 (25 - 1 ?m) the observed performance gracefully degrades to R ? 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to ˜4 K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials—Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder—are characterized and presented.

Wollack, E. J.; Kinzer, R. E.; Rinehart, S. A.

2014-04-01

243

Cryogenic thermal control technology summaries  

NASA Technical Reports Server (NTRS)

A summarization and categorization is presented of the pertinent literature associated with cryogenic thermal control technology having potential application to in-orbit fluid transfer systems and/or associated space storage. Initially, a literature search was conducted to obtain pertinent documents for review. Reports determined to be of primary significance were summarized in detail. Each summary, where applicable, consists of; (1) report identification, (2) objective(s) of the work, (3) description of pertinent work performed, (4)major results, and (5) comments of the reviewer (GD/C). Specific areas covered are; (1) multilayer insulation of storage tanks with and without vacuum jacketing, (2) other insulation such as foams, shadow shields, microspheres, honeycomb, vent cooling and composites, (3) vacuum jacketed and composite fluid lines, and (4) low conductive tank supports and insulation penetrations. Reports which were reviewed and not summarized, along with reasons for not summarizing, are also listed.

Stark, J. A.; Leonhard, K. E.; Bennett, F. O., Jr.

1974-01-01

244

A cryogenic infrared calibration target.  

PubMed

A compact cryogenic calibration target is presented that has a peak diffuse reflectance, R ? 0.003, from 800?to?4800?cm(-1) (12 - 2??m). Upon expanding the spectral range under consideration to 400-10,000?cm(-1) (25 - 1??m) the observed performance gracefully degrades to R ? 0.02 at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to ?4 K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials-Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder-are characterized and presented. PMID:24784638

Wollack, E J; Kinzer, R E; Rinehart, S A

2014-04-01

245

The Nuclear Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

The fundamental capability of Nuclear Thermal Propulsion (NTP) is game changing for space exploration. A first generation Nuclear Cryogenic Propulsion Stage (NCPS) based on NTP could provide high thrust at a specific impulse above 900 s, roughly double that of state of the art chemical engines. Characteristics of fission and NTP indicate that useful first generation systems will provide a foundation for future systems with extremely high performance. The role of the NCPS in the development of advanced nuclear propulsion systems could be analogous to the role of the DC-3 in the development of advanced aviation. Progres made under the NCPS project could help enable both advanced NTP and advanced Nuclear Electric Propulsion (NEP).

Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Doughty, Glen; Belvin, Anthony; Borowski, Stanley K.; Scott, John

2014-01-01

246

Brush seals for cryogenic applications  

NASA Astrophysics Data System (ADS)

This viewgraph presentation presents test results of brush seals for cryogenic applications. Leakage for a single brush seal was two to three times less than for a 12-tooth labyrinth seal. The maximum temperature rise for a single brush seal was less than 50 R and occurred at 25 psid across the seal and 35,000 rpm. A static blowout test demonstrated sealing capability up to 550 psid. The seal limit was not obtained. The power loss for a single brush at 35,000 rpm and 175 psid was 2.45 hp. Two brushes far apart leak less than two brushes tight packed. Rotor wear was approximately 0.00075 mils and bristle wear was 1-3 mils after 4-1/2 hours.

Proctor, Margaret P.

1994-07-01

247

Computed tomography of cryogenic cells  

SciTech Connect

Due to the short wavelengths of X-rays and low numerical aperture of the Fresnel zone plates used as X-ray objectives, the depth of field is several microns. Within the focal depth, imaging a thick specimen is to a good approximation equivalent to projecting the specimen absorption. Therefore, computed tomography based on a tilt series of X-ray microscopic images can be used to reconstruct the local linear absorption coefficient and image the three-dimensional specimen structure. To preserve the structural integrity of biological objects during image acquisition, microscopy is performed at cryogenic temperatures. Tomography based on X-ray microscopic images was applied to study the distribution of male specific lethal 1 (MSL-1), a nuclear protein involved in dosage compensation in Drosophila melanogaster, which ensures that males with single X chromosome have the same amount of most X-linked gene products as females with two X chromosomes. Tomographic reconstructions of X-ray microscopic images were used to compute the local three-dimensional linear absorption coefficient revealing the arrangement of internal structures of Drosophila melanogaster cells. Combined with labelling techniques, nanotomography is a new technique to study the 3D distribution of selected proteins inside whole cells. We want to improve this technique with respect to resolution and specimen preparation. The resolution in the reconstruction can be significantly improved by reducing the angular step size to collect more viewing angles, which requires an automated data acquisition. In addition, fast-freezing with liquid ethane instead of cryogenic He gas will be applied to improve the vitrification of the hydrated samples. We also plan to apply cryo X-ray nanotomography in order to study different types of cells and their nuclear protein distributions.

Schneider, Gerd; Anderson, E.; Vogt, S.; Knochel, C.; Weiss, D.; LeGros, M.; Larabell, C.

2001-08-30

248

Dense dust structures in cryogenic complex plasma  

NASA Astrophysics Data System (ADS)

In the previous researches of cryogenic complex (dusty) plasma [1] we observed experimentally complex plasma systems formed in cryogenic environments. Particularly it was revealed from the experiments that dust structures with high concentration of macroparticles can be formed. So-called super dense dusty plasma structures in which interparticle distance is comparable with particle size were also observed. Thus concentration of particles was close to concentration of background plasma. Similar formations had unusual properties (sphere-like form, free boundaries, etc.) and represent new object in dusty plasma researches. In the present work new results on experimental investigations of dense dust structures at cryogenic temperatures were presented. The experiments were made by means of recently developed techniques and cryogenic facilities (optical cryostat). Possible nature of the unusual properties of super dense dusty plasma structures was discussed.

Antipov, S. N.; Vasiliev, M. M.; Alyapyshev, M. M.; Petrov, O. F.; Fortov, V. E.

2014-05-01

249

Cryogenic liquid transfer system reduces residual boiloff  

NASA Technical Reports Server (NTRS)

System for transferring cryogenic liquids to a dewar prevents boiloff of residual liquid by venting the boiloff to the atmosphere during the transfer tube cooling period. The system is most useful with liquids having very small heat of vaporization.

Hegland, D. E.

1966-01-01

250

Space propulsion technology and cryogenic fluid depot  

NASA Technical Reports Server (NTRS)

Information on space propulsion and technology and the cryogenic fluid depot is given in viewgraph form. Information is given on orbit transfer, electric propulsion, spacecraft propulsion, and program objectives.

Diehl, Larry A.

1988-01-01

251

Evaluation of two designs for cryogenic insulation  

NASA Technical Reports Server (NTRS)

Shingle-type, crinkled, aluminized polyethylene ester is thermally and structurally tested for cryogenic insulation. Insulation systems require thermal efficiency with minimum weight, and the ability to withstand vibration, acceleration, and rapid pressure drops.

Getty, R. C.

1970-01-01

252

The Fast Alternative Cryogenic Experiment Testbed  

NASA Technical Reports Server (NTRS)

One of the challenges in the area of cryogenics for space exploration in the next millennium is providing the capability for inexpensive, frequent, access to space. Faced with this challenge during the International Space Station (ISS) build era, when other Space Shuttle manifesting opportunities are unavailable, a "proof of concept" cryostat has been developed to demonstrate the ability to accommodate low temperature science investigations within the constraints of the Hitchhiker siderail carrier. The Hitchhiker siderail carrier is available on a "mass available" basis during the ISS build era. In fact, several hitchhiker payloads flew with the deployment of the Unity module. Hitchhiker siderail carrier payloads have historically flown an average of about four times a year. A hybrid Solid Neon - Superfluid Helium cryostat has been developed with Janis Research Company to accommodate instruments of 16.5 cm diameter and 30 cm. length. This hybrid approach was taken in part to provide adequate on-orbit lifetime for instruments with high (conducted) heat loads from the instrumentation wiring. Mass, volume, lifetime and the launch hold scenario were all design drivers. In addition, with Ball Aerospace and Technologies Corporation, a multichannel VME architecture Germanium Resistance Thermometer (GRT) readout and heater control servo system has been developed. In a flight system, the cryostat and electronics payloads would be umbilically attached in a paired Hitchhiker siderail mount, and permit on-orbit command and telemetry capability. The results of performance tests of both the cryostat, and a helium sample instrument will be presented. The instrument features a self contained, miniaturized, nano-Kelvin resolution High Resolution Thermometer (HRT). This high level of thermal resolution is achieved through the utilization of a dc Superconducting Quantum Interference Device (SQUID). Although developed for the Low Temperature Microgravity Fundamental Physics investigator community, many design features are applicable in fields such as infrared and x-ray astronomy.

Nash, Alfred; Holmes, Warren

2000-01-01

253

Visual-Inspection Probe For Cryogenic Chamber  

NASA Technical Reports Server (NTRS)

Visual-inspection probe that resembles borescope enables observer at ambient temperature to view objects immersed in turbulent flow of liquid oxygen, liquid nitrogen, or other cryogenic fluid. Design of probe fairly conventional, except special consideration given to selection of materials and to thermal expansion to provide for expected range of operating temperatures. Penetrates wall of cryogenic chamber to provide view of interior. Similar probe illuminates scene. View displayed on video monitor.

Friend, Steve; Valenzuela, James; Yoshinaga, Jay

1990-01-01

254

Filament-wound, fiberglass cryogenic tank supports  

NASA Technical Reports Server (NTRS)

The design, fabrication, and testing of filament-wound, fiberglass cryogenic tank supports for a LH2 tank, a LF2/FLOX tank and a CH4 tank. These supports consist of filament-wound fiberglass tubes with titanium end fittings. These units were satisfactorily tested at cryogenic temperatures, thereby offering a design that can be reliably and economically produced in large or small quantities. The basic design concept is applicable to any situation where strong, lightweight axial load members are desired.

Carter, J. S.; Timberlake, T. E.

1971-01-01

255

FET's Perform Well At Cryogenic Temperatures  

NASA Technical Reports Server (NTRS)

New metal-oxide-semiconductor field-effect transistors designed for source-follower preamplifiers operating at liquid-helium temperatures in conjunction with infrared detectors. Lower thresholds and offset give CryoFET's greater dynamic range and linearity than conventional MOSFET's at low temperatures and facilitates pair balancing to reduce offsets in output. Reduces heat loading of cryogenic system, extending life, reliability, and performance of cryogenic infrared instruments.

Sclar, N.

1992-01-01

256

Creep of pure aluminum at cryogenic temperatures  

E-print Network

CREEP OF PURE ALUMINUM AT CRYOGENIC TEMPERATURES A Thesis by LACY CLARK MCDONALD Submitted to the Office of Graduate Studies of Texas AgrM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August... 1989 Major Subject: Mechanical Engineering CREEP OF PURE ALUMINUM AT CRYOGENIC TEMPERATURES A Thesis by LACY CLARK MCDONALD Approved a. s to style and content by: K. Ted Hartwig (Chair ol' Committee) Walter L. Bradley (Member) Mehrda. d...

McDonald, Lacy Clark

1989-01-01

257

Demonstration of Microsphere Insulation in Cryogenic Vessels  

Microsoft Academic Search

While microspheres have been recognized as a legitimate insulation material for decades, actual use in full-scale cryogenic storage tanks has not been demonstrated until now. The performance and life-cycle-cost advantages previously predicted have now been proven. Most bulk cryogenic storage tanks are insulated with either multilayer insulation (MLI) or perlite. Microsphere insulation, consisting of hollow glass bubbles, combines in a

R. G. Baumgartner; E. A. Myers; J. E. Fesmire; D. L. Morris; E. R. Sokalski

2006-01-01

258

Large Cryogenic Germanium Detector. Final Report  

SciTech Connect

The goal of this project was to investigate possible ways of increasing the size of cryogenic Ge detectors. This project identified two possible approaches to increasing the individual cryogenic Ge detector size. The first approach relies on using the existing technology for growing detector-grade (high-purity) germanium crystals of dislocation density 100-7000 cm{sup -2}. The second approach is to consider dislocation-free Ge crystals.

Mandic, Vuk

2013-02-13

259

Flight Performance of the AKARI Cryogenic System  

E-print Network

We describe the flight performance of the cryogenic system of the infrared astronomical satellite AKARI, which was successfully launched on 2006 February 21 (UT). AKARI carries a 68.5 cm telescope together with two focal plane instruments, Infrared Cameras (IRC) and Far Infrared Surveyor (FIS), all of which are cooled down to cryogenic temperature to achieve superior sensitivity. The AKARI cryogenic system is a unique hybrid system, which consists of cryogen (liquid helium) and mechanical coolers (2-stage Stirling coolers). With the help of the mechanical coolers, 179 L (26.0 kg) of super-fluid liquid helium can keep the instruments cryogenically cooled for more than 500 days. The on-orbit performance of the AKARI cryogenics is consistent with the design and pre-flight test, and the boil-off gas flow rate is as small as 0.32 mg/s. We observed the increase of the major axis of the AKARI orbit, which can be explained by the thrust due to thermal pressure of vented helium gas.

Nakagawa, Takao; Hirabayashi, Masayuki; Kaneda, Hidehiro; Kii, Tsuneo; Kimura, Yoshiyuki; Matsumoto, Toshio; Murakami, Hiroshi; Murakami, Masahide; Narasaki, Katsuhiro; Narita, Masanao; Ohnishi, Akira; Tsunematsu, Shoji; Yoshida, Seiji

2007-01-01

260

D0 Cryogenic System Operator Training  

SciTech Connect

D0 is a collider detector. It will be operating and doing physics at the same time as CDP, therefore it has been decided to train CDP operators to operate and respond to the D0 cryogenic control system. A cryogenic operator will be required to be in residence at D0, during the cooldown and liquid Argon fill of any of the calorimeters. The cryogenic system at D0 is designed to be unmanned during steady state operation. CDP operations has 2 man cryogenic shifts 24 hours a day. It is intended that CDP operators monitor the D0 cryogenic systems, evaluate and respond to alarms, and notify a D0 cryo expert in the event of an unusual problem. A D0 cryogenic system view node has been installed at CDP to help facilitate these goals. It should be noted that even though the CDP view node is a fully operational node it is intended that it be more of an information node and is therefore password protected. The D0 cryo experts may reassess the use of the CDP node at a later date based on experience and operating needs. This engineering note outlines the format of the training and testing given to the CDP operators to make them qualified D0 operators.

Markley, D.; /Fermilab

1991-11-30

261

Flight Performance of the AKARI Cryogenic System  

E-print Network

We describe the flight performance of the cryogenic system of the infrared astronomical satellite AKARI, which was successfully launched on 2006 February 21 (UT). AKARI carries a 68.5 cm telescope together with two focal plane instruments, Infrared Cameras (IRC) and Far Infrared Surveyor (FIS), all of which are cooled down to cryogenic temperature to achieve superior sensitivity. The AKARI cryogenic system is a unique hybrid system, which consists of cryogen (liquid helium) and mechanical coolers (2-stage Stirling coolers). With the help of the mechanical coolers, 179 L (26.0 kg) of super-fluid liquid helium can keep the instruments cryogenically cooled for more than 500 days. The on-orbit performance of the AKARI cryogenics is consistent with the design and pre-flight test, and the boil-off gas flow rate is as small as 0.32 mg/s. We observed the increase of the major axis of the AKARI orbit, which can be explained by the thrust due to thermal pressure of vented helium gas.

Takao Nakagawa; Keigo Enya; Masayuki Hirabayashi; Hidehiro Kaneda; Tsuneo Kii; Yoshiyuki Kimura; Toshio Matsumoto; Hiroshi Murakami; Masahide Murakami; Katsuhiro Narasaki; Masanao Narita; Akira Ohnishi; Shoji Tsunematsu; Seiji Yoshida

2007-08-14

262

Measurement of heat flux and heat transfer coefficient during continuous cryogen spray cooling for laser dermatologic surgery  

Microsoft Academic Search

Cryogen spray cooling (CSC) has been used for selective epidermal cooling of human skin during laser therapy of patients with port wine stain (PWS) birthmarks. Unfortunately, current commercial CSC devices do not provide optimal cooling selectivity and, therefore, provide insufficient epidermal protection for some PWS patients. To assist in the development of improved atomizing nozzle designs, a reliable method to

Guillermo Aguilar; Wim Verkruysse; Boris Majaron; Lars O. Svaasand; Enrique J. Lavernia; J. Stuart Nelson

2001-01-01

263

Specification and Design of the SBRC-190: A Cryogenic Multiplexer for Far Infrared Photoconductor Detectors  

NASA Technical Reports Server (NTRS)

Arrays of far-infrared photoconductor detectors operate at a few degrees Kelvin and require electronic amplifiers in close proximity. For the electronics, a cryogenic multiplexer is ideal to avoid the large number of wires associated with individual amplifiers for each pixel, and to avoid adverse effects of thermal and radiative heat loads from the circuitry. For low background applications, the 32 channel CRC 696 CMOS device was previously developed for SIRTF, the cryogenic Space Infrared Telescope Facility. For higher background applications, we have developed a similar circuit, featuring several modifications: (a) an AC coupled, capacitive feedback transimpedence unit cell, to minimize input offset effects, thereby enabling low detector biases, (b) selectable feedback capacitors to enable operation over a wide range of backgrounds, and (c) clamp and sample & hold output circuits to improve sampling efficiency, which is a concern at the high readout rates required. We describe the requirements for and design of the new device.

Erickson, E. F.; Young, E. T.; Wolf, J.; Asbrock, J. F.; Lum, N.; DeVincenzi, D. (Technical Monitor)

2002-01-01

264

Ceramic Fiber Structures for Cryogenic Load-Bearing Applications  

NASA Technical Reports Server (NTRS)

This invention is intended for use as a load-bearing device under cryogenic temperatures and/or abrasive conditions (i.e., during missions to the Moon). The innovation consists of small-diameter, ceramic fibers that are woven or braided into devices like ropes, belts, tracks, or cables. The fibers can be formed from a variety of ceramic materials like silicon carbide, carbon, aluminosilicate, or aluminum oxide. The fiber architecture of the weave or braid is determined by both the fiber properties and the mechanical requirements of the application. A variety of weave or braid architectures is possible for this application. Thickness of load-bearing devices can be achieved by using either a 3D woven structure, or a layered, 2D structure. For the prototype device, a belt approximately 0.10 in. (0.25 cm) thick, and 3.0 in. (7.6 cm) wide was formed by layering and stitching a 2D aluminosilicate fiber weave.

Jaskowiak, Martha H.; Eckel, Andrew J.

2009-01-01

265

Cryogenic pellet production developments for long-pulse plasma operation  

NASA Astrophysics Data System (ADS)

Long pulse plasma operation on large magnetic fusion devices require multiple forms of cryogenically formed pellets for plasma fueling, on-demand edge localized mode (ELM) triggering, radiative cooling of the divertor, and impurity transport studies. The solid deuterium fueling and ELM triggering pellets can be formed by extrusions created by helium cooled, twin-screw extruder based injection system that freezes deuterium in the screw section. A solenoid actuated cutter mechanism is activated to cut the pellets from the extrusion, inserting them into the barrel, and then fired by the pneumatic valve pulse of high pressure gas. Fuel pellets are injected at a rate up to 10 Hz, and ELM triggering pellets are injected at rates up to 20 Hz. The radiative cooling and impurity transport study pellets are produced by introducing impurity gas into a helium cooled section of a pipe gun where it deposits in-situ. A pneumatic valve is opened and propellant gas is released downstream where it encounters a passive punch which initially accelerates the pellet before the gas flow around the finishes the pellet acceleration. This paper discusses the various cryogenic pellet production techniques based on the twin-screw extruder, pipe gun, and pellet punch designs.

Meitner, S. J.; Baylor, L. R.; Combs, S. K.; Fehling, D. T.; McGill, J. M.; Duckworth, R. C.; McGinnis, W. D.; Rasmussen, D. A.

2014-01-01

266

Gamma Radiation Induced Calibration Shift for Four Cryogenic Thermometer Types  

NASA Astrophysics Data System (ADS)

Cryogenic temperature sensors utilized in space environments are exposed to ionizing radiation with the total dose dependent upon the length of the mission. Based upon their minimal size and robust packaging, four models of cryogenic Resistance Thermometer Devices (RTDs) manufactured by Lake Shore Cryotronics, Inc. were tested to determine their reliability for space applications with regard to radiation. Samples of Cernox™ RTDs (CX-1050-SD), ruthenium oxide RTDs (models RX-102A-AA and RX-103A-AA), and silicon diode thermometers (model DT-670-SD) were irradiated at room temperature by a cesium-137 gamma source to total doses ranging from 5 Gy to 10 kGy. This paper presents the resulting temperature shifts induced by the gamma radiation as a function of total dose over the 1.4 K to 325 K temperature range. These data show that 1) Cernox™ RTDs exhibit high radiation hardness to 10 kGy from 1.4 K to 325 K, 2) ruthenium oxide RTDs show moderate radiation hardness to 10 kGy below 10 K, and 3) silicon diodes temperature sensors exhibit some radiation tolerance to low levels of radiation (especially below 70 K), but quickly shift calibration at radiation levels above 300 Gy, especially above 100 K.

Courts, S. Scott; Yeager, C. J.

2004-06-01

267

Carbon nanotube electrical-substitution cryogenic radiometer: initial results.  

PubMed

A carbon nanotube cryogenic radiometer (CNCR) has been fabricated for electrical-substitution optical power measurements. The CNCR employs vertically aligned multiwall carbon nanotube arrays (VANTAs) as the absorber, heater, and thermistor, with a micromachined silicon substrate as the weak thermal link. Compared to conventional cryogenic radiometers, the CNCR is simpler, more easily reproduced and disseminated, orders of magnitude faster, and can operate over a wide range of wavelengths without the need for a receiver cavity. We describe initial characterization results of the radiometer at 3.9 K, comparing electrical measurements and fiber-coupled optical measurements from 50 ?W to 1.5 mW at the wavelength of 1550 nm. We find the response to input electrical and optical power is equivalent to within our measurement uncertainty, which is currently limited by the experimental setup (large temperature fluctuations of the cold stage) rather than the device itself. With improvements in the temperature stability, the performance of the CNCR should be limited only by our ability to measure the reflectance of the optical absorber VANTA. PMID:23454953

Tomlin, N A; Lehman, J H

2013-01-15

268

Engineering and fabrication cost considerations for cryogenic wind tunnel models  

NASA Technical Reports Server (NTRS)

Design and fabrication cost drivers for cryogenic transonic wind tunnel models are defined. The major cost factors for wind tunnel models are model complexity, tolerances, surface finishes, materials, material validation, and model inspection. The cryogenic temperatures require the use of materials with relatively high fracture toughness but at the same time high strength. Some of these materials are very difficult to machine, requiring extensive machine hours which can add significantly to the manufacturing costs. Some additional engineering costs are incurred to certify the materials through mechanical tests and nondestructive evaluation techniques, which are not normally required with conventional models. When instrumentation such as accelerometers and electronically scanned pressure modules is required, temperature control of these devices needs to be incorporated into the design, which requires added effort. Additional thermal analyses and subsystem tests may be necessary, which also adds to the design costs. The largest driver to the design costs is potentially the additional static and dynamic analyses required to insure structural integrity of the model and support system.

Boykin, R. M., Jr.; Davenport, J. B., Jr.

1983-01-01

269

Electronic Components and Systems for Cryogenic Space Applications  

NASA Technical Reports Server (NTRS)

Electronic components and systems capable of operation at cryogenic temperatures are anticipated in many future NASA space missions such as deep space probes and planetary surface exploration. For example, an unheated interplanetary probe launched to explore the rings of Saturn would reach an average temperature near Saturn of about - 183 C. In addition to surviving the deep space harsh environment, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing payload development and launch costs. Terrestrial applications where components and systems must operate in low temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. An on-going research and development program at the NASA Glenn Research Center focuses on the development of reliable electronic devices and efficient power systems capable of surviving in low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. Ongoing research activities that are being performed in collaboration with various organizations will also be presented.

Patterson, R. L.; Hammoud, A.; Dickman, J. E.; Gerber, S.; Elbuluk, M. E.; Overton, E.

2001-01-01

270

On 32-GHz cryogenically cooled HEMT low-noise amplifiers  

NASA Technical Reports Server (NTRS)

The cryogenic noise temperature performance of a two-stage and a three-stage 32 GHz High Electron Mobility Transistor (HEMT) amplifier was evaluated. The amplifiers employ 0.25 micrometer conventional AlGaAs/GaAs HEMT devices, hybrid matching input and output microstrip circuits, and a cryogenically stable dc biasing network. The noise temperature measurements were performed in the frequency range of 31 to 33 GHz over a physical temperature range of 300 K down to 12 K. Across the measurement band, the amplifiers displayed a broadband response, and the noise temperature was observed to decrease by a factor of 10 in cooling from 300 K to 15 K. The lowest noise temperature measured for the two-stage amplifier at 32 GHz was 35 K with an associated gain of 16.5 dB, while the three-stage amplifier measured 39 K with an associated gain of 26 dB. It was further observed that both amplifiers were insensitive to light.

Bautista, J. J.; Ortiz, G. G.; Duh, K. H. G.; Kopp, W. F.; Ho, P.; Chao, P. C.; Kao, M. Y.; Smith, P. M.; Ballingall, J. M.

1988-01-01

271

Cryogenic pellet production developments for long-pulse plasma operation  

SciTech Connect

Long pulse plasma operation on large magnetic fusion devices require multiple forms of cryogenically formed pellets for plasma fueling, on-demand edge localized mode (ELM) triggering, radiative cooling of the divertor, and impurity transport studies. The solid deuterium fueling and ELM triggering pellets can be formed by extrusions created by helium cooled, twin-screw extruder based injection system that freezes deuterium in the screw section. A solenoid actuated cutter mechanism is activated to cut the pellets from the extrusion, inserting them into the barrel, and then fired by the pneumatic valve pulse of high pressure gas. Fuel pellets are injected at a rate up to 10 Hz, and ELM triggering pellets are injected at rates up to 20 Hz. The radiative cooling and impurity transport study pellets are produced by introducing impurity gas into a helium cooled section of a pipe gun where it deposits in-situ. A pneumatic valve is opened and propellant gas is released downstream where it encounters a passive punch which initially accelerates the pellet before the gas flow around the finishes the pellet acceleration. This paper discusses the various cryogenic pellet production techniques based on the twin-screw extruder, pipe gun, and pellet punch designs.

Meitner, S. J.; Baylor, L. R.; Combs, S. K.; Fehling, D. T.; McGill, J. M.; Duckworth, R. C.; McGinnis, W. D.; Rasmussen, D. A. [Oak Ridge National Laboratory, 1Bethel Valley Rd Oak Ridge, TN 37831 (United States)

2014-01-29

272

IC-compatible processing of inertial sensors using SF6-O2 cryogenic plasma process  

Microsoft Academic Search

An IC-technology compatible process lor high aspect ratio trench based microinertial devices was developed, using cryogenic SF6-O2 plasma etching as a single postprocessing step. Furthermore it involves either silicon to silicon dry etch BCB bonding, Si wafer thinning and a method for front-to-backside alignment using ASML PAS5000\\/50 waferstepper. The wafer thinning is performed using TMAH wet etching bringing the advantage

G. Craciun; H. Yang; L. Pakula; P. J. French; M. A. Blauw; E. van der Drift

2003-01-01

273

Cryogenic On-Orbit Liquid Depot Storage, Acquisition, and Transfer Satellite (COLD-SAT)  

Microsoft Academic Search

The Cryogenic On-Orbit Liquid Depot Storage, Acquisition, and Transfer Satellite (COLD-SAT) will perform subcritical liquid hydrogen handling experiments under low gravity conditions to provide engineering data for future space transportation missions. Comprising the four Class 1 enabling experiments are tank press control, tank chilldown, tank no-vent fill, and liquid acquisition device fill\\/refill. The nine Class 2 enhancing experiments are tanker

John R. Schuster; Edwin J. Russ; Joseph P. Wachter

1990-01-01

274

Performance of the SBRC 190, a cryogenic multiplexer for photoconductor arrays  

NASA Technical Reports Server (NTRS)

The SBRC 190 cryogenic readouts were developed for use with far-infrared arrays of Ge:Sb and Ge:Ga photoconductor detectors. The SBRC 190 provides an AC-coupled CTIA (capacitance transimpedance amplifier) unit cell for each detector and multiplexes up to 32 detectors. This paper presents our test results characterizing and optimizing the performance of these novel devices. We will discuss their basic behavior in addition to describing the trade-offs inherent in different sampling strategies.

Dotson, Jessie L.; Koerber, C. T.; Mason, C. G.; Simpson, J. P.; Moore, E. M.; Witteborn, F. C.; Farhoomand, J.; Erickson, E. F.; DeVincenzi, D. (Technical Monitor)

2002-01-01

275

Cryogenic characterization and testing of magnetically-actuated microshutter arrays for the James Webb Space Telescope  

Microsoft Academic Search

Two-dimensional MEMS microshutter arrays (MSA) have been fabricated at the NASA Goddard Space Flight Center (GSFC) for the James Webb Space Telescope (JWST) to enable cryogenic (~35 K) spectrographic astronomy measurements at near-infrared wavelengths. Functioning as a focal plane object selection device, the MSA is a 2D programmable aperture mask with fine resolution, high efficiency and high contrast. The MSA

T. T. King; G. Kletetschka; M. A. Jah; M. A. Beamesderfer; M. J. Li; L. L. Wang; S. H. Moseley; L. M. Sparr; M. D. Jhabvala; A. S. Kutyrev; R. F. Silverberg; D. Rapchun; Y. Zheng; D. S. Schwinger; G. M. Voellmer

2005-01-01

276

Cryogenic characterization and testing of magnetically-actuated microshutter arrays for the James Webb Space Telescope  

Microsoft Academic Search

Two-dimensional MEMS microshutter arrays (MSA) have been fabricated at the NASA Goddard Space Flight Center (GSFC) for the James Webb Space Telescope (JWST) to enable cryogenic (?35 K) spectrographic astronomy measurements at near-infrared wavelengths. Functioning as a focal plane object selection device, the MSA is a 2D programmable aperture mask with fine resolution, high efficiency and high contrast. The MSA

T T King; G Kletetschka; M A Jah; M A Beamesderfer; M J Li; L L Wang; S H Moseley; L M Sparr; M D Jhabvala; A S Kutyrev; R F Silverberg; D Rapchun; Y Zheng; D S Schwinger; G M Voellmer

2005-01-01

277

Thermodynamic Vent System for an On-Orbit Cryogenic Reaction Control Engine  

NASA Technical Reports Server (NTRS)

A report discusses a cryogenic reaction control system (RCS) that integrates a Joule-Thompson (JT) device (expansion valve) and thermodynamic vent system (TVS) with a cryogenic distribution system to allow fine control of the propellant quality (subcooled liquid) during operation of the device. It enables zero-venting when coupled with an RCS engine. The proper attachment locations and sizing of the orifice are required with the propellant distribution line to facilitate line conditioning. During operations, system instrumentation was strategically installed along the distribution/TVS line assembly, and temperature control bands were identified. A sub-scale run tank, full-scale distribution line, open-loop TVS, and a combination of procured and custom-fabricated cryogenic components were used in the cryogenic RCS build-up. Simulated on-orbit activation and thruster firing profiles were performed to quantify system heat gain and evaluate the TVS s capability to maintain the required propellant conditions at the inlet to the engine valves. Test data determined that a small control valve, such as a piezoelectric, is optimal to provide continuously the required thermal control. The data obtained from testing has also assisted with the development of fluid and thermal models of an RCS to refine integrated cryogenic propulsion system designs. This system allows a liquid oxygenbased main propulsion and reaction control system for a spacecraft, which improves performance, safety, and cost over conventional hypergolic systems due to higher performance, use of nontoxic propellants, potential for integration with life support and power subsystems, and compatibility with in-situ produced propellants.

Hurlbert, Eric A.; Romig, Kris A.; Jimenez, Rafael; Flores, Sam

2012-01-01

278

Argon SDC detector cryogenic design  

SciTech Connect

A first cut at designing the cryogenic systems is resented. The point design or sample design presented includes flow-rate calculations, piping sizes, dewar elevations, etc. In summary, the analysis shows argon cooling is ample even with relatively small piping, headers, dewar elevations, etc. This will afford the designer considerable latitude to change the design as required to meet other system requirements. For example, dewar elevation above the detector and horizontal distance to the detector could be varied to meet hall-space requirements. The point design shows a simple system with only one argon supply-and-return pipe to the detector. No nitrogen cooling is required at the detector. No seals or piping (except for an open supply and return header) are required in the detector and a minimum, of baffling to director argon flow is required. No thermal insulation is required to protect modules from pre-amp heat. A simple temperature control technique for the argon loop using a single nitrogen dewar and heat exchanger is shown.

Slack, D.S.

1991-10-25

279

A Cryogenic Infrared Calibration Target  

E-print Network

A compact cryogenic calibration target is presented that has a peak diffuse reflectance, $R \\le 0.003$, from $800-4,800\\,{\\rm cm}^{-1}$ $(12-2\\,\\mu$m). Upon expanding the spectral range under consideration to $400-10,000\\,{\\rm cm}^{-1}$ $(25-1\\,\\mu$m) the observed performance gracefully degrades to $R \\le 0.02$ at the band edges. In the implementation described, a high-thermal-conductivity metallic substrate is textured with a pyramidal tiling and subsequently coated with a thin lossy dielectric coating that enables high absorption and thermal uniformity across the target. The resulting target assembly is lightweight, has a low-geometric profile, and has survived repeated thermal cycling from room temperature to $\\sim4\\,$K. Basic design considerations, governing equations, and test data for realizing the structure described are provided. The optical properties of selected absorptive materials -- Acktar Fractal Black, Aeroglaze Z306, and Stycast 2850 FT epoxy loaded with stainless steel powder -- are character...

Wollack, Edward J; Rinehart, Stephan A

2014-01-01

280

Cryogenic System for the Spallation Neutron Source  

SciTech Connect

The Spallation Neutron Source (SNS) is a neutron-scattering facility being built at Oak Ridge, TN for the US Department of Energy. The SNS accelerator linac consists of superconducting radio-frequency (SRF) cavities in cryostats (cryomodules). The linac cryomodules are cooled to 2.1 K by a 2300 watt cryogenic refrigeration system. As an SNS partner laboratory, Jefferson Lab is responsible for the installed integrated cryogenic system design for the SNS linac accelerator consisting of major subsystem equipment engineered and procured from industry. Jefferson Lab's work included developing the major vendor subsystem equipment procurement specifications, equipment procurement, and the integrated system engineering support of the field installation and commissioning. The major cryogenic system components include liquid nitrogen storage, gaseous helium storage, cryogen distribution transfer line system, 2.1-K cold box consisting of four stages of cold compressors, 4.5-K cold box, warm helium compressors with its associated oil removal, gas management, helium purification, gas impurity monitoring systems, and the supportive utilities of electrical power, cooling water and instrument air. The system overview, project organization, the important aspects, and the capabilities of the cryogenic system are described.

Arenius, D.; Chronis, W.; Creel, J.; Dixon, K.; Ganni, V.; Knudsen, P. [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue, Newport News, VA 23606 (United States)

2004-06-23

281

Cryogenic Applications of Commercial Electronic Components  

NASA Technical Reports Server (NTRS)

We have developed a range of techniques useful for constructing analog and digital circuits for operation in a liquid Helium environment (4.2K), using commercially available low power components. The challenges encountered in designing cryogenic electronics include finding components that can function usefully in the cold and possess low enough power dissipation so as not to heat the systems they are designed to measure. From design, test, and integration perspectives it is useful for components to operate similarly at room and cryogenic temperatures; however this is not a necessity. Some of the circuits presented here have been used successfully in the MUSTANG and in the GISMO camera to build a complete digital to analog multiplexer (which will be referred to as the Cryogenic Address Driver board). Many of the circuit elements described are of a more general nature rather than specific to the Cryogenic Address Driver board, and were studied as a part of a more comprehensive approach to addressing a larger set of cryogenic electronic needs.

Buchanan, Ernest D.; Benford, Dominic J.; Forgione, Joshua B.; Moseley, S. Harvey; Wollack, Edward J.

2012-01-01

282

Aerogel Blanket Insulation Materials for Cryogenic Applications  

NASA Technical Reports Server (NTRS)

Aerogel blanket materials for use in thermal insulation systems are now commercially available and implemented by industry. Prototype aerogel blanket materials were presented at the Cryogenic Engineering Conference in 1997 and by 2004 had progressed to full commercial production by Aspen Aerogels. Today, this new technology material is providing superior energy efficiencies and enabling new design approaches for more cost effective cryogenic systems. Aerogel processing technology and methods are continuing to improve, offering a tailor-able array of product formulations for many different thermal and environmental requirements. Many different varieties and combinations of aerogel blankets have been characterized using insulation test cryostats at the Cryogenics Test Laboratory of NASA Kennedy Space Center. Detailed thermal conductivity data for a select group of materials are presented for engineering use. Heat transfer evaluations for the entire vacuum pressure range, including ambient conditions, are given. Examples of current cryogenic applications of aerogel blanket insulation are also given. KEYWORDS: Cryogenic tanks, thermal insulation, composite materials, aerogel, thermal conductivity, liquid nitrogen boil-off

Coffman, B. E.; Fesmire, J. E.; White, S.; Gould, G.; Augustynowicz, S.

2009-01-01

283

Cryogenic applications of commercial electronic components  

NASA Astrophysics Data System (ADS)

We have developed a range of techniques useful for constructing analog and digital circuits for operation in a liquid Helium environment (4.2 K), using commercially available low power components. The challenges encountered in designing cryogenic electronics include finding components that can function usefully in the cold and possess low enough power dissipation so as not to heat the systems they are designed to measure. From design, test, and integration perspectives it is useful for components to operate similarly at room and cryogenic temperatures; however this is not a necessity. Some of the circuits presented here have been used successfully in the MUSTANG [1] and in the GISMO [2] camera to build a complete digital to analog multiplexer (which will be referred to as the Cryogenic Address Driver board). Many of the circuit elements described are of a more general nature rather than specific to the Cryogenic Address Driver board, and were studied as a part of a more comprehensive approach to addressing a larger set of cryogenic electronic needs.

Buchanan, Ernest D.; Benford, Dominic J.; Forgione, Joshua B.; Harvey Moseley, S.; Wollack, Edward J.

2012-10-01

284

Status of the ESS cryogenic system  

NASA Astrophysics Data System (ADS)

The European Spallation Source (ESS) is a neutron science facility funded by a collaboration of 17 European countries currently under design and construction in Lund, Sweden. The centerpiece of ESS is a 2.5 GeV proton linac utilizing superconducting RF cavities operating at 2 K. In addition to cooling the SRF cavities, cryogenics is also used at ESS in the liquid hydrogen moderators surrounding the target. ESS also uses both liquid helium and liquid nitrogen in a number of the planned neutron instruments. There is also a significant cryogenic installation associated with the site acceptance testing of the ESS cryomodules. The ESS cryogenic system consists of 3 separate helium refrigeration/liquefaction plants supplying the accelerator, target moderators and instruments. An extensive cryogenic distribution system connects the accelerator cryoplant with the cryomodules. This paper describes the preliminary design of the ESS cryogenic system including the expected heat loads. Challenges associated with the required high reliability and turn-down capability will also be discussed. A unique feature of ESS is its commitment to sustainability and energy recovery. A conceptual design for recovering waste heat from the helium compressors for use in the Lund district heating system will also be described.

Weisend, J. G., II; Darve, C.; Gallimore, S.; Hees, W.; Jurns, J.; Köttig, T.; Ladd, P.; Molloy, S.; Parker, T.; Wang, X. L.

2014-01-01

285

Advanced cryogenics for cutting tools. Final report  

SciTech Connect

The purpose of the investigation was to determine if cryogenic treatment improved the life and cost effectiveness of perishable cutting tools over other treatments or coatings. Test results showed that in five of seven of the perishable cutting tools tested there was no improvement in tool life. The other two tools showed a small gain in tool life, but not as much as when switching manufacturers of the cutting tool. The following conclusions were drawn from this study: (1) titanium nitride coatings are more effective than cryogenic treatment in increasing the life of perishable cutting tools made from all cutting tool materials, (2) cryogenic treatment may increase tool life if the cutting tool is improperly heat treated during its origination, and (3) cryogenic treatment was only effective on those tools made from less sophisticated high speed tool steels. As a part of a recent detailed investigation, four cutting tool manufacturers and two cutting tool laboratories were queried and none could supply any data to substantiate cryogenic treatment of perishable cutting tools.

Lazarus, L.J.

1996-10-01

286

Cryogenic measurements of aerojet GaAs n-JFETs  

NASA Technical Reports Server (NTRS)

The spectral noise characteristics of Aerojet gallium arsenide (GaAs) junction field effect transistors (JFET's) have been investigated down to liquid-helium temperatures. Noise characterization was performed with the field effect transistor (FET) in the floating-gate mode, in the grounded-gate mode to determine the lowest noise readings possible, and with an extrinsic silicon photodetector at various detector bias voltages to determine optimum operating conditions. The measurements indicate that the Aerojet GaAs JFET is a quiet and stable device at liquid helium temperatures. Hence, it can be considered a readout line driver or infrared detector preamplifier as well as a host of other cryogenic applications. Its noise performance is superior to silicon (Si) metal oxide semiconductor field effect transistor (MOSFET's) operating at liquid helium temperatures, and is equal to the best Si n channel junction field effect transistor (n-JFET's) operating at 300 K.

Goebel, John H.; Weber, Theodore T.

1993-01-01

287

Study of magnetic properties of a cryogenic temperature sensor diode  

NASA Astrophysics Data System (ADS)

The magnetic properties of a cryogenic silicon diode temperature sensor (Lake Shore) are studied in the temperature range 5-255 K using a superconducting quantum interference device magnetometer. The M vs H curve at 5 and 250 K showed practically negligible magnetic hysteresis. The magnetization in a field of 100 Oe is found to be temperature independent to within 10% in the temperature range 5-255 K. The observed magnetization comes mainly from the packaging materials which includes ferromagnetic Kovar leads and nickel plating. We suggest a change of the construction materials. Our measurements show that, the existing diodes, if used in close proximity to the sample, in magnetization measurements, can be conveniently used only after background calibration.

Ota, S. B.; Mishra, P. K.; Sahni, V. C.; Singh, M. R.; Bascuñán, Juan

2000-04-01

288

Cryogenic optomechanics with a 261kHz mechanical oscillator  

NASA Astrophysics Data System (ADS)

Mechanical motion can interact with light via radiation pressure force. With recent experimental advances over the last few years, such optomechanical coupling has been used to reach quantum ground state of mechanical oscillators, which opens interesting new regime of observing quantum mechanics in macroscopic objects. The optomechanical devices used in this talk consist of a dielectric SiN membrane located inside a high finesse optical cavity. Combining cryogenic cooling in He3 refrigerator and resolved sideband laser cooling enables us to cool the membrane's mechanical mode (whose mechanical frequency is 261kHz) to less than 60 phonons. We will describe some technical challenges in our experiments such as the role of classical phase noise of the cooling laser at the mechanical frequency and our efforts to significantly reduce it via a filter cavity.

Lee, Donghun; Jayich, Andrew; Sankey, Jack; Yang, Chen; Childress, Lily; Underwood, Mitchell; Borkje, Kjetil; Girvin, Steve; Harris, Jack

2012-02-01

289

Operational Experience with the LHC Superconducting Links and Evaluation of Possible Cryogenic Schemes for Future Remote Powering of Superconducting Magnets  

E-print Network

In the LHC, a large number of superconducting magnets are powered remotely by 5 superconducting links at distances of 70 up to 520 m. This innovation allowed choosing more convenient locations for installing the electrical feedboxes and their related equipment. The consolidations performed after the first commissioning campaign and the operational experience with the superconducting links over a period of several months are presented. Based on the successful application of superconducting links in the LHC, such devices can be envisaged for powering future accelerator magnets. Several possible cryogenic configurations for future superconducting links are presented with their respective figures of merit from the cryogenic and practical implementation point of view.

Perin, A; Claudet, S

2010-01-01

290

Fractional watt Vuillemier cryogenic refrigerator program engineering notebook. Volume 1: Thermal analysis  

NASA Technical Reports Server (NTRS)

The cryogenic refrigerator thermal design calculations establish design approach and basic sizing of the machine's elements. After the basic design is defined, effort concentrates on matching the thermodynamic design with that of the heat transfer devices (heat exchangers and regenerators). Typically, the heat transfer device configurations and volumes are adjusted to improve their heat transfer and pressure drop characteristics. These adjustments imply that changes be made to the active displaced volumes, compensating for the influence of the heat transfer devices on the thermodynamic processes of the working fluid. Then, once the active volumes are changed, the heat transfer devices require adjustment to account for the variations in flows, pressure levels, and heat loads. This iterative process is continued until the thermodynamic cycle parameters match the design of the heat transfer devices. By examing several matched designs, a near-optimum refrigerator is selected.

Miller, W. S.

1974-01-01

291

Design of a precision etalon position control system for a cryogenic spectrometer  

NASA Technical Reports Server (NTRS)

The Upper Atmosphere Research Satellite (UARS) will be launched in 1988 to study the distribution of a series of trace elements in the upper atmosphere and to study atmospheric dynamics. The UARS carries on board a cryogenically cooled infrared spectrometer to measure the concentration of a series of chemical species that are important for understanding the ozone layer in the stratosphere. This device, known as the Cryogenic Limb Array Etalon Spectrometer (CLAES), uses a multiposition filter wheel combined with tilt-scanned Fabry Perot etalons to obtain the high resolution required for these experiments. The CLAES optical system is sealed in a dewar where it is maintained at cryogenic temperatures by a supply of solid hydrogen. Operating temperatures for CLAES range from 130 K at the entrance aperture to 13 K at the focal plane. The design and test of a special control system using a unique actuator concept to provide position and can control for the CLAES etalon are described. Results of performance tests at cryogenic temperatures simulating the CLAES on-orbit environment are discussed.

Aubrun, J. N.; Lorell, K. R.; Zacharie, D. F.; Thatcher, J. B.

1984-01-01

292

Ultra-low vibration linear stirling cryogenic refrigerator for sub-nano resolution microscopy  

NASA Astrophysics Data System (ADS)

Wide use of so called "dry-cooling" technology, eventually replacing the LN2 cooling approach in high-resolution instrumentation, such as Scanning Electronic Microscopes, Helium Ion Microscopes, Superconductive Quantum Interference Devices, etc., motivates further quieting of appropriate cryogenic refrigerators. Linear Stirling cryogenic refrigerators are known to be a major source of harmful vibration export compromising the overall performance of vibration-sensitive equipment. The dual-piston approach to a design of a linear compressor yields inherently low vibration export and, therefore, is widely accepted across the industry. However, the residual vibration disturbance originated even from the technological tolerances, natural wear and contamination cannot be completely eliminated. Moreover, a vibration disturbance produced by a pneumatically driven cold head is much more powerful as compared to this of a compressor. The authors successfully redesigned the existing Ricor model K535 Stirling cryogenic refrigerator for use in vibration-sensitive electronic microscopy, where the image resolution is specified in angstroms. The objective was achieved by passive mechanical counterbalancing of the expander portion of the refrigerator, in a combination with an active two-axis control of residual vibrations, relying on National Instruments CompactRIO hardware, incorporating a real-time processor and reconfigurable FPGA for reliable stand-alone embedded application, developed using LabVIEW graphical programming tools. The attainable performance of the Ultra-Low Vibration linear Stirling cryogenic refrigerator RICOR model K535-ULV was evaluated through the full-scale experimentation.

Riabzev, S. V.; Veprik, A. M.; Vilenchik, H. S.; Pundak, N.; Castiel, E.

2008-04-01

293

Viscosity of Cryoprotective Agents Near Glass Transition: A New Device, Technique, and Data on DMSO, DP6,  

E-print Network

part of the cryogenic temperature range (where the CPA has a comparatively low viscosity of the cryogenic temperature range is largely unavailable. A new measurement device is presented in this study forming ice. It has been found that depressing the homogeneous nucleation temperature until it equals

Rabin, Yoed

294

Conceptual design of the FRIB cryogenic system  

SciTech Connect

The Facility for Rare Isotope Beams (FRIB) is a new nuclear science facility funded by the DOE Office of Science and Michigan State University (MSU). FRIB is currently under design and will be located on the MSU campus. The centerpiece of FRIB is a heavy ion linac utilizing superconducting RF cavities and magnets which in turn requires a large cryogenic system. The cryogenic system consists of a commercially produced helium refrigeration plant and an extensive distribution system. Superconducting components will operate at both 4.5 K and 2 K. This paper describes the conceptual design of the system including the expected heat loads and operating modes. The strategy for procuring a custom turnkey helium refrigeration plant from industry, an overview of the distribution system, the interface of the cryogenic system to the conventional facilities and the project schedule are also described.

Weisend II, J G; Bull, Brad; Burns, Chris; Fila, Adam; Kelley, Patrick; Laumer, Helmut; Mann, Thomas; McCartney, Allyn; Jones, S

2012-06-01

295

A survey of cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

Following the development of the cryogenic wind tunnel at the NASA Langley Research Center in 1972, a large number of cryogenic wind-tunnel projects have been undertaken at various research establishments around the world. The purpose of this paper is to describe some of the more significant of these projects. Described in this paper are cryogenic wind-tunnel projects in China (CARDC), England (College of Aeronautics at Cranfield, RAE-Bedford, and University of Southampton), 'Europe' (Pilot European Transonic Windtunnel at NAL-Amsterdam, and the European Transonic Windtunnel proposed for DFVLR-Koeln), France (ONERA-CERT), Germany (DFVLR-Koeln, and DFVLR-Goettingen), Japan (NAL, University of Tsukuba, and National Defense Academy), Sweden (Rollab), and the United States (Douglas Aircraft Co., University of Illinois at Urbana-Champaign, and NASA-Langley).

Kilgore, R. A.; Dress, D. A.

1985-01-01

296

The Management of Cryogens at CERN  

E-print Network

CERN is a large user of industrially procured cryogens essentially liquid helium and nitrogen. Recent contracts have been placed by the Organization for the delivery of quantities up to 280 tons of liquid helium over four years and up to 50000 tons of liquid nitrogen over three years. Main users are the very large cryogenic system of the LHC accelerator complex, the physics experiments using superconducting magnets and liquefied gases and all the related test facilities whether industrial or laboratory scale. With the commissioning of LHC, the need of cryogens at CERN will considerably increase and the procurement policy must be adapted accordingly. In this paper, we discuss procurement strategy for liquid helium and nitrogen, including delivery rates, distribution methods and adopted safety standards. Global turnover, on site re-liquefaction capacity, operational consumption, accidental losses, purification means and storage capacity will be described. Finally, the short to medium term evolution of the Orga...

Delikaris, D; Passardi, Giorgio; Serio, L; Tavian, L

2005-01-01

297

Spacelab 2 infrared telescope cryogenic system  

NASA Technical Reports Server (NTRS)

The paper discusses the development of a cryogenic helium system to provide cooling to a scanning infrared telescope for the Spacelab 2 mission. The infrared optical/detector system and related electronics are being developed by the Smithsonian Astrophysical Observatory and the University of Arizona. A superfluid helium dewar and porous plug phase separator permit gas cooling of the infrared focal plane assembly to about 2.5 K, and of the two telescope sections to 8 K and 60 K. The design of the cryogenic system,including a commandable vacuum cover, and the prelaunch liquid helium servicing and maintenance approach were discussed. It is concluded that the system will satisfy the Infrared Telescope requirements, and the superfluid helium system shall be capable of satisfying cryogenic helium cooled requirements for the next several years.

Urban, E. W.; Katz, L.; Hendricks, J. B.; Karr, G. R.

1979-01-01

298

Performance of Power Converters at Cryogenic Temperatures  

NASA Technical Reports Server (NTRS)

Power converters capable of operation at cryogenic temperatures are anticipated to play an important role in the power system architecture of future NASA deep space missions. Design of such converters to survive cryogenic temperatures will improve the power system performance and reduce development and launch costs. Aerospace power systems are mainly a DC distribution network. Therefore, DC/DC and DC/AC converters provide the outputs needed to different loads at various power levels. Recently, research efforts have been performed at the NASA Glenn Research Center (GRC) to design and evaluate DC/DC converters that are capable of operating at cryogenic temperatures. This paper presents a summary of the research performed to evaluate the low temperature performance of five DC/DC converters. Various parameters were investigated as a function of temperature in the range of 20 to -196 C. Data pertaining to the output voltage regulation and efficiency of the converters is presented and discussed.

Elbuluk, Malik E.; Gerber, Scott; Hammoud, Ahmad; Patterson, Richard L.

2001-01-01

299

Development of dual solid cryogens for high reliability refrigeration system  

NASA Technical Reports Server (NTRS)

High reliability solid cryogen refrigeration system consists of a container initially filled with a solid cryogen which is coupled thermally to an infrared detector by means of a link of high thermal conductivity extending from a heat exchanger within the cryogen container.

Caren, R. P.; Coston, R. M.

1967-01-01

300

Microstructure of cryogenic treated M2 tool steel  

Microsoft Academic Search

Cryogenic treatment has been claimed to improve wear resistance of certain steels and has been implemented in cutting tools, autos, barrels etc. Although it has been confirmed that cryogenic treatment can improve the service life of tools, the underling mechanism remains unclear. In this paper, we studied the microstructure changes of M2 tool steel before and after cryogenic treatment. We

J. Y Huang; Y. T Zhu; X. Z Liao; I. J Beyerlein; M. A Bourke; T. E Mitchell

2003-01-01

301

Two-Phase Cryogenic Heat Exchanger for the Thermodynamic Vent System  

NASA Technical Reports Server (NTRS)

A two-phase cryogenic heat exchanger for a thermodynamic vent system was designed and analyzed, and the predicted performance was compared with test results. A method for determining the required size of the Joule-Thomson device was also developed. Numerous sensitivity studies were performed to show that the design was robust and possessed a comfortable capacity margin. The comparison with the test results showed very similar heat extraction performance for similar inlet conditions. It was also shown that estimates for Joule- Thomson device flow rates and exit quality can vary significantly and these need to be accommodated for with a robust system design.

Christie, Robert J.

2011-01-01

302

Far-infrared calibration sources for use in cryogenic telescopes  

NASA Astrophysics Data System (ADS)

IR calibration sources have been built using a 'reverse bolometer' approach. A NiCr thin film is deposited on a thin sapphire chip, forming a robust, resistive heater with high emissivity. The heater is suspended within a metal ring using nylon fibers, and electrically connected with low thermal conductivity wires. Finished devices may be mounted directly ona cryostat work surface and provide a wide range of greybody output with minimal power dissipation to the cold bath. Under typical operating conditions, a 40K equivalent blackbody output can be obtained with 1 to 2 mW electrical input power. The time constant varies according to type of device and specified temperature, but ranges from 100 ms to seconds. Accelerated lifetime test show output repeatability to within +/- 0.8 percent throughout 94,000 cycles from 4.2 K to 60K. The devices have survived shake testing at cryogenic temperatures and will be used for in- flight array calibration in the Multiband Imaging Photometer for SIRTF instrument, a part of the SIRTF.

Beeman, Jeffrey W.; Haller, Eugene E.

2002-02-01

303

Conceptual design of pressure relief systems for cryogenic application  

SciTech Connect

The conceptual design of pressure relief systems is an important aspect in the early phase of any cryogenic system design, because a prudent and responsible evaluation of relief systems involves much more than just relief devices. The conceptual design consists of various steps: At first, hazard scenarios must be considered and the worst-case scenario identified. Next, a staged interaction against pressure increase is to be defined. This is followed by the selection of the general type of pressure relief device for each stage, such as safety valve and rupture disc, respectively. Then, a decision concerning their locations, their capacities and specific features must be taken. Furthermore, it is mandatory to consider the inlet pressure drop and the back pressure in the exhaust line for sizing the safety devices. And last but not least, economic and environmental considerations must be made in case of releasing the medium to the atmosphere. The development of the system's safety concept calls for a risk management strategy based on identification and analysis of hazards, and consequent risk mitigation using a system-based approach in compliance with the standards.

Grohmann, S. [Institute for Technical Thermodynamics and Refrigeration, Karlsruhe Institute of Technology, Engler-Bunte-Ring 21, 76131 Karlsruhe, Germany and Institute for Technical Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 E (Germany); Süßer, M. [Institute for Technical Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2014-01-29

304

Cryogenic electron beam induced chemical etching.  

PubMed

Cryogenic cooling is used to enable efficient, gas-mediated electron beam induced etching (EBIE) in cases where the etch rate is negligible at room and elevated substrate temperatures. The process is demonstrated using nitrogen trifluoride (NF3) as the etch precursor, and Si, SiO2, SiC, and Si3N4 as the materials volatilized by an electron beam. Cryogenic cooling broadens the range of precursors that can be used for EBIE, and enables high-resolution, deterministic etching of materials that are volatilized spontaneously by conventional etch precursors as demonstrated here by NF3 and XeF2 EBIE of silicon. PMID:25333843

Martin, Aiden A; Toth, Milos

2014-11-12

305

Sorption cryogenic refrigeration - Status and future  

NASA Technical Reports Server (NTRS)

The operation principles of sorption cryogenic refrigeration are discussed. Sorption refrigerators have virtually no wear-related moving parts, have negligible vibration, and offer extremely long life (at least ten years), making it possible to obtain efficient, long life and low vibration cooling to as low as 7 K for cryogenic sensors. The physisorption and chemisorption systems recommended for various cooling ranges down to 7 K are described in detail. For long-life cooling at 4-5 K temperatures, a hybrid chemisorption-mechanical refrigeration system is recommended.

Jones, Jack A.

1988-01-01

306

A cryogenic helium II system for Spacelab  

NASA Technical Reports Server (NTRS)

A description is presented of a helium II storage and gas delivery system which is to provide refrigeration to a scanning infrared telescope experiment which will be flown in space in 1981 aboard the Spacelab 2 mission. Instead of submerging the infrared apparatus within a large, specially constructed helium dewar, which has been the usual approach to space cryogenics, it was decided to separate the cooled infrared optical system from the storage dewar. As a result of this decision the cryogenic supply system will be able to deliver gaseous or liquid helium cooling to other types of experiments on later Spacelab missions.

Urban, E. W.; Katz, L.; Hendricks, J. B.; Karr, G. R.

1978-01-01

307

Thermoelectric Module Performance in Cryogenic Temperature  

NASA Astrophysics Data System (ADS)

Performance of thermoelectric (TE) modules for the TE power conversion system combined with open rack type LNG vaporizer (ORV) is discussed. Most of the conventional BiTe TE modules suffer sudden decrease of the power at cryogenic temperature as low as -160°C. This is called as Mayer-Marschall effect. Authors investigated the cause of this effect and found TE modules that could avoid such effect. Performance data of such TE modules obtained at the cryogenic thermoelectric (CTE) test rig which could realize temperature and fluid dynamic condition of the ORV is presented.

Kambe, Mitsuru; Morita, Ryo; Omoto, Kazuyuki; Koji, Yasuhiro; Yoshida, Tatsuo; Noishiki, Koji

308

Experimental research on the residual magnetization of a rare-earth permanent magnet for a cryogenic undulator  

NASA Astrophysics Data System (ADS)

The magnetic properties of commercial polycrystalline Nd2Fe14B (N50M, N45H, N40SH, N35EH) and Sm2Co17 (XG30/20, XG26/25, XG22/20) magnets at cryogenic temperatures were tested by using a comprehensive physical properties measurement system (PPMS). The results show that the spin tilt temperature Tst of Nd2Fe14B magnets is closely related to intrinsic coercivity Hci, N50M and N45H with smaller Hci show a residual magnetization jump at 235 K and 225 K, respectively. For Sm2Co17 magnets, in 50-300 K, with temperature decreasing, residual magnetization Mrc shows a nearly linear increase, while in 10-50 K, Mrc has little change. The research results provide a reference for cryogenic undulators and other high-precision cryogenic devices.

He, Yong-Zhou

2013-07-01

309

CRYOGENIC AND VACUUM TECHNOLOGICAL ASPECTS OF THE LOW-ENERGY ELECTROSTATIC CRYOGENIC STORAGE RING  

SciTech Connect

The cryogenic and vacuum concepts for the electrostatic Cryogenic ion Storage Ring (CSR), under construction at the Max-Planck-Institut fuer Kernphysik in Heidelberg, is presented. The ring will operate in a broad temperature range from 2 to 300 K and is required to be bakeable up to 600 K. Extremely high vacuum and low temperatures are necessary to achieve long lifetimes of the molecular ions stored in the ring so that the ions will have enough time to cool by radiation to their vibrational and rotational ground states. To test cryogenic and vacuum technological aspects of the CSR, a prototype is being built and will be connected to the commercial cryogenic refrigerator recently installed, including a specialized 2-K connection system. The first results and the status of current work with the prototype are also presented.

Orlov, D. A.; Lange, M.; Froese, M.; Hahn, R. von; Grieser, M.; Mallinger, V.; Sieber, T.; Weber, T.; Wolf, A. [Max-Planck-Institut fuer Kernphysik, Heidelberg, 69029 Germany (Germany); Rappaport, M. [Weizmann Institute of Science, Rehovot 76100 (Israel)

2008-03-16

310

Method of measuring heat influx of a cryogenic transfer system  

DOEpatents

A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

Niemann, Ralph C. (Downers Grove, IL); Zelipsky, Steven A. (Tinley Park, IL); Rezmer, Ronald R. (Lisle, IL); Smelser, Peter (Bruner, MO)

1981-01-01

311

ANALYSIS AND DESIGN OF CRYOGENIC BALL VALVE  

Microsoft Academic Search

Natural gas is being hailed as alternative energy sources for a petroleum, because it is almost no emissions of pollutants in the environment. Use of equipment for liquefied natural gas, along with increased demand for natural gas is also growing. Cryogenic ball valve is used to control the liquified natural gas which temperature is -196 , supplied pressure ?? is

Dong-Soo KIM; Myoung-Sub KIM

2008-01-01

312

Elastic vacuum seal for cryogenic temperatures  

SciTech Connect

Cold-hardened silicone rubber is proposed as a vacuum seal in units that contain materials with vastly different expansion coefficients and which operate at cryogenic temperatures. The cold vulcanization process and the polymerization catalyst used to accelerate and stabilize the process are described. Test results obtained for vacuum tightness in liquid nitrogen are assessed.

Kolenko, E.A.

1988-06-01

313

Cost-Efficient Storage of Cryogens  

NASA Technical Reports Server (NTRS)

NASA's cryogenic infrastructure that supports launch vehicle operations and propulsion testing is reaching an age where major refurbishment will soon be required. Key elements of this infrastructure are the large double-walled cryogenic storage tanks used for both space vehicle launch operations and rocket propulsion testing at the various NASA field centers. Perlite powder has historically been the insulation material of choice for these large storage tank applications. New bulk-fill insulation materials, including glass bubbles and aerogel beads, have been shown to provide improved thermal and mechanical performance. A research testing program was conducted to investigate the thermal performance benefits as well as to identify operational considerations and associated risks associated with the application of these new materials in large cryogenic storage tanks. The program was divided into three main areas: material testing (thermal conductivity and physical characterization), tank demonstration testing (liquid nitrogen and liquid hydrogen), and system studies (thermal modeling, economic analysis, and insulation changeout). The results of this research work show that more energy-efficient insulation solutions are possible for large-scale cryogenic storage tanks worldwide and summarize the operational requirements that should be considered for these applications.

Fesmire, J. E.; Sass, J. P.; Nagy, Z.; Sojoumer, S. J.; Morris, D. L.; Augustynowicz, S. D.

2007-01-01

314

Cryogenics Testbed Laboratory Flange Baseline Configuration  

NASA Technical Reports Server (NTRS)

As an intern at Kennedy Space Center (KSC), I was involved in research for the Fluids and Propulsion Division of the NASA Engineering (NE) Directorate. I was immersed in the Integrated Ground Operations Demonstration Units (IGODU) project for the majority of my time at KSC, primarily with the Ground Operations Demonstration Unit Liquid Oxygen (GODU L02) branch of IGODU. This project was established to develop advancements in cryogenic systems as a part of KSC's Advanced Exploration Systems (AES) program. The vision of AES is to develop new approaches for human exploration, and operations in and beyond low Earth orbit. Advanced cryogenic systems are crucial to minimize the consumable losses of cryogenic propellants, develop higher performance launch vehicles, and decrease operations cost for future launch programs. During my internship, I conducted a flange torque tracking study that established a baseline configuration for the flanges in the Simulated Propellant Loading System (SPLS) at the KSC Cryogenics Test Laboratory (CTL) - the testing environment for GODU L02.

Acuna, Marie Lei Ysabel D.

2013-01-01

315

Cryogenic Heat Exchanger with Turbulent Flows  

ERIC Educational Resources Information Center

An evaporator-type cryogenic heat exchanger is designed and built for introducing fluid-solid heat exchange phenomena to undergraduates in a practical and efficient way. The heat exchanger functions at liquid nitrogen temperature and enables cooling of N[subscript 2] and He gases from room temperatures. We present first the experimental results of…

Amrit, Jay; Douay, Christelle; Dubois, Francis; Defresne, Gerard

2012-01-01

316

Exergy analysis of cryogenic air separation  

Microsoft Academic Search

An exergy analysis is performed to analyse the possibilities of fuel saving in the cryogenic distillation process, which is the main method of air separation. It is shown that more than half of the exergy loss takes place in the liquefaction unit and almost one-third in the air compression unit. Minor exergy losses are taking place in the distillation unit

R. L. Cornelissen; G. G. Hirs

1998-01-01

317

Cryogenic air separation with cold argon recycle  

Microsoft Academic Search

The invention provides an efficient means of increasing oxygen purity and recovery and also argon recovery in cryogenic distillative air separation plants. In addition, the invention makes it possible to increase the oxygen delivery pressure from high efficiency triple pressure configurations without using an oxygen vacuum compressor. These advantages are obtained by incorporating an argon recycle compressor within the cold

Erickerson

1985-01-01

318

Efficiencies of trays in cryogenic distillation columns  

Microsoft Academic Search

This Paper considers the behaviour of the distillation trays in conventional use in cryogenic air separation plants. An earlier study showed that the trays should operate at higher efficiencies than plant experience would indicate. This conclusion was based on the assumption of uniform liquid flow across the trays. In practice, stagnant zones can occur which reduce the efficiency. A study

M. W. Biddulph

1986-01-01

319

Cryogenic Fuel Tank Draining Analysis Model  

NASA Technical Reports Server (NTRS)

One of the technological challenges in designing advanced hypersonic aircraft and the next generation of spacecraft is developing reusable flight-weight cryogenic fuel tanks. As an aid in the design and analysis of these cryogenic tanks, a computational fluid dynamics (CFD) model has been developed specifically for the analysis of flow in a cryogenic fuel tank. This model employs the full set of Navier-Stokes equations, except that viscous dissipation is neglected in the energy equation. An explicit finite difference technique in two-dimensional generalized coordinates, approximated to second-order accuracy in both space and time is used. The stiffness resulting from the low Mach number is resolved by using artificial compressibility. The model simulates the transient, two-dimensional draining of a fuel tank cross section. To calculate the slosh wave dynamics the interface between the ullage gas and liquid fuel is modeled as a free surface. Then, experimental data for free convection inside a horizontal cylinder are compared with model results. Finally, cryogenic tank draining calculations are performed with three different wall heat fluxes to demonstrate the effect of wall heat flux on the internal tank flow field.

Greer, Donald

1999-01-01

320

Cryogenic Laser Calorimetry for Impurity Analysis  

NASA Technical Reports Server (NTRS)

The results of a one-year effort to determine the applicability of laser-calorimetric spectroscopy to the study of deep-level impurities in silicon are presented. Critical considerations for impurity analysis by laser-calorimetric spectroscopy are discussed, the design and performance of a cryogenic laser calorimeter is described, and measurements of background absorption in high-purity silicon are presented.

Swimm, R. T.

1985-01-01

321

Jacketed cryogenic piping is stress relieved  

NASA Technical Reports Server (NTRS)

Jacketed design of piping used to transfer cryogenic fluids, relieves severe stresses associated with the temperature gradients that occur during transfer cycles and ambient periods. The inner /transfer/ pipe is preloaded in such a way that stress relief takes place automatically as cycling occurs.

Bowers, W. M.

1967-01-01

322

Inflatable-Seal Assembly For Cryogenic Fluids  

NASA Technical Reports Server (NTRS)

Connector for cryogenic fluid lines quickly joined or separated, seals tightly, and reduces transfer of heat to fluid. Features redundant sealing rings inflated after joining so they wedge tightly against connector base, preventing leakage. Cylinder of FEP inflatable. Pair of threaded stainless-steel rings - one at each end of cylinder - secure cylinder in quick-disconnect assembly.

Buehler, Kurt; Fesmire, James E.

1989-01-01

323

Fiber optic level sensor for cryogens  

NASA Technical Reports Server (NTRS)

Sensor is useful in cryogenic environments where liquids of very low index of refraction are encountered. It is "yes/no" indication of whether liquid is in contact with sensor. Sharp bends in fiber alter distribution of light among propagation modes. This amplifies change in light output observed when sensor contacts liquid, without requiring long fiber that would increse insertion loss.

Sharma, M.

1981-01-01

324

Cryogenic thermoelectric thermometer using a heat tube  

SciTech Connect

An original application of heat tubes is proposed for increasing the accuracy of cryogenic temperature measurement. This is achieved by supplementary action on the working end of the thermocouple, based on the tube`s heat energy transmission, controlled by a magnetic field.

Skripnik, Yu.A.; Khimicheva, A.I.

1995-09-01

325

A cryogenic torsion pendulum: progress report  

Microsoft Academic Search

A cryogenic torsion pendulum for gravitational experiments is being refined at its remote operation site near Richland, Washington. Features of the apparatus include: four stages of temperature control, an angular readout of the pendulum about three orthogonal axes and a remote operation capability. Currently, we are testing the apparatus with a nominally symmetric pendulum suspended from a 25 µm diameter

M. K. Bantel; R. D. Newman

2000-01-01

326

Cryogenic gyroscopes for the relativity mission  

Microsoft Academic Search

The relativity mission, also known as gravity probe B (GP-B), uses high-precision electrostatically suspended cryogenic gyroscopes for measuring the relativistic precessions of the frame of reference in a 650 km polar orbit. A 2 K environment is used to ensure the thermal stability and to implement the readout technique based on the magnetic dipole moment generated by a rotating superconductor.

Saps Buchman; C. W. F Everitt; Brad Parkinson; J. P Turneaure; G. M Keiser

2000-01-01

327

Adjustable expandable cryogenic piston and ring  

Microsoft Academic Search

The operation of a reciprocating expansion engine for cryogenic refrigeration is improved by changing the pistons and rings so that the piston can be operated from outside the engine to vary the groove in which the piston ring is located. This causes the ring, which is of a flexible material, to be squeezed so that its contact with the wall

P. O. Mazur; C. B. Pallaver

1980-01-01

328

Miniature cryogenic expansion turbines - A review  

Microsoft Academic Search

Lord Rayleigh (1898) has first suggested the use of a turbine instead of a piston expander for the liquification of air. The development of expansion turbines is discussed, taking into account the first successful commercial application for cryogenic expansion turbines in Germany, Kapitza's turbine, work on much smaller turbines conducted in England, the development of a helium expansion turbine at

H. Sixsmith

1984-01-01

329

Adjustable expandable cryogenic piston and ring  

Microsoft Academic Search

The operation of a reciprocating expansion engine for cryogenic refrigeration is improved by changing the pistons and rings so that the piston can be operated from outside the engine to vary the groove in which the piston ring is located. This causes the ring, which is of a flexible material, to be squeezed so that its contact with the wall

P. O. Mazur; C. B. Pallaver

1978-01-01

330

A cryogenic fiber maker for continuous extrusion  

Microsoft Academic Search

A cryogenic fiber maker that continuously extrudes fibers is presented. The design of the fiber maker is based on the use of two cooling stages maintained at different temperatures. The fiber maker consists of two copper reservoirs that are connected in series and are kept at different temperatures. The first reservoir is used to liquefy the gas coming in from

R. Aliaga-Rossel; J. Bayley

1998-01-01

331

Cryogenically enhanced magneto-Archimedes levitation  

Microsoft Academic Search

The application of both a strong magnetic field and magnetic field gradient to a diamagnetic body can produce a vertical force which is sufficient to counteract its weight due to gravity. By immersing the body in a paramagnetic fluid, an additional adjustable magneto-buoyancy force is generated which enhances the levitation effect. Here we show that cryogenic oxygen and oxygen–nitrogen mixtures

A T Catherall; P López-Alcaraz; K A Benedict; P J King; L Eaves

2005-01-01

332

Energy Efficient Storage and Transfer of Cryogens  

NASA Technical Reports Server (NTRS)

Cryogenics is globally linked to energy generation, storage, and usage. Thermal insulation systems research and development is an enabling part of NASA's technology goals for Space Launch and Exploration. New thermal testing methodologies and materials are being transferred to industry for a wide range of commercial applications.

Fesmire, James E.

2013-01-01

333

Robust Multilayer Insulation for Cryogenic Systems  

NASA Technical Reports Server (NTRS)

New requirements for thermal insulation include robust Multilayer insulation (MU) systems that work for a range of environments from high vacuum to no vacuum. Improved MLI systems must be simple to install and maintain while meeting the life-cycle cost and thermal performance objectives. Performance of actual MLI systems has been previously shown to be much worse than ideal MLI. Spacecraft that must contain cryogens for both lunar service (high vacuum) and ground launch operations (no vacuum) are planned. Future cryogenic spacecraft for the soft vacuum environment of Mars are also envisioned. Industry products using robust MLI can benefit from improved cost-efficiency and system safety. Novel materials have been developed to operate as excellent thermal insulators at vacuum levels that are much less stringent than the absolute high vacuum requirement of current MLI systems. One such robust system, Layered Composite Insulation (LCI), has been developed by the Cryogenics Test Laboratory at NASA Kennedy Space Center. The experimental testing and development of LCI is the focus of this paper. LCI thermal performance under cryogenic conditions is shown to be six times better than MLI at soft vacuum and similar to MLI at high vacuum. The experimental apparent thermal conductivity (k-value) and heat flux data for LCI systems are compared with other MLI systems.

Fesmire, J. E.; Scholtens, B. F.; Augustynowicz, S. D.

2007-01-01

334

Cryogenic propellant prestart conditioning for NLS  

NASA Technical Reports Server (NTRS)

An overview is presented of a candidate National Launch System (NLS) passive cryogenic propellant prestart conditioning system that offers a stable propellant thermal environment and minimum system complexity. A 2D, multinode model utilizing real fluid properties was developed. This model predicts flow recirculation due to thermal gradients by assuming vertical cold and warm opposing flow streams produced by density differential.

Gaynor, T. L.; Merlin, M. V.; Gautney, T. T.

1992-01-01

335

Subcooling for Long Duration In-Space Cryogenic Propellant Storage  

NASA Technical Reports Server (NTRS)

Cryogenic propellants such as hydrogen and oxygen are crucial for exploration of the solar system because of their superior specific impulse capability. Future missions may require vehicles to remain in space for months, necessitating long-term storage of these cryogens. A Thermodynamic Cryogen Subcooler (TCS) can ease the challenge of cryogenic fluid storage by removing energy from the cryogenic propellant through isobaric subcooling of the cryogen below its normal boiling point prior to launch. The isobaric subcooling of the cryogenic propellant will be performed by using a cold pressurant to maintain the tank pressure while the cryogen's temperature is simultaneously reduced using the TCS. The TCS hardware will be integrated into the launch infrastructure and there will be no significant addition to the launched dry mass. Heat leaks into all cryogenic propellant tanks, despite the use of the best insulation systems. However, the large heat capacity available in the subcooled cryogenic propellants allows the energy that leaks into the tank to be absorbed until the cryogen reaches its operational thermodynamic condition. During this period of heating of the subcooled cryogen there will be minimal loss of the propellant due to venting for pressure control. This simple technique can extend the operational life of a spacecraft or an orbital cryogenic depot for months with minimal mass penalty. In fact isobaric subcooling can more than double the in-space hold time of liquid hydrogen compared to normal boiling point hydrogen. A TCS for cryogenic propellants would thus provide an enhanced level of mission flexibility. Advances in the important components of the TCS will be discussed in this paper.

Mustafi, Shuvo; Johnson, Wesley; Kashani, Ali; Jurns, John; Kutter, Bernard; Kirk, Daniel; Shull, Jeff

2010-01-01

336

Energy Efficiency of large Cryogenic Systems: the LHC Case and Beyond  

E-print Network

Research infrastructures for high-energy and nuclear physics, nuclear fusion and production of high magnetic fields are increasingly based on applied superconductivity and associated cryogenics in their quest for scientific breakthroughs at affordable capital and operation costs, a condition for their acceptance and sustained funding by society. The thermodynamic penalty for operating at low temperature makes energy efficiency a key requirement for their large cryogenic systems, from conceptual design to procurement, construction and operation. Meeting this requirement takes a combined approach on several fronts in parallel: management of heat loads and sizing of cooling duties, distribution of cooling power matching the needs of the superconducting devices, efficient production of refrigeration, optimal control resting on precise instrumentation and diagnostics, as well as a targeted industrial procurement policy. The case of the Large Hadron Collider (LHC) at CERN is presented. Potential improvements for fu...

Claudet, S; Ferlin, G; Lebrun, P; Tavian, L; Wagner, U

2013-01-01

337

Test of a trail cryogenic balance in the ONERA T2 wind tunnel  

NASA Technical Reports Server (NTRS)

The three component cryogenic balance designed and manufactured by the ONERA Large Means Directorate, was equipped with a light alloy schematic model and tested at the end of 1984 at the T2 wind tunnel in gusts at low temperatures up to 120 K. The tests pertained to the impact of the cryogenic conditions on the behavior of extensometric bridges while cooling the balance-model system mounted in the conditioning device and during gusts with models in the test section. A few tests with thermal disequilibrium between the flow and balance made it possible to confirm the proper operation in the range 120 to 300 K. This gust system showed that the balance, which was well compensated thermally, may be used in T2 with and without precooling. For any thermal gradient, the analysis was always performed with the same matrices and aerodynamic coefficients were obtained with the same precision.

Blanchard, A.; Seraudie, A.; Plazanet, M.; Payry, M. J.

1987-01-01

338

Cryogenic ferromagnetic patterns with controlled magnetization for superconducting phase-shift elements  

NASA Astrophysics Data System (ADS)

The magnetic field generated by cryogenic PdNi ferromagnetic patterns was controlled at 4.2 K to fabricate superconducting phase-shift elements (PSEs) that would lead to production of energy-efficient devices. Cryogenic ferromagnetic patterns of Pd0.89Ni0.11 were magnetized by field cooling (FC) involving the application of external magnetic fields during sample cooling. The magnetic field from the PdNi patterns was evaluated by examining rectangular Josephson junctions in the vicinity of the patterns. Our experimental results show that the strength of the field induced by the PdNi patterns was nearly proportional to the applied field strength during FC. The field strength also depended on the end temperature of FC.

Taniguchi, Soya; Ito, Hiroshi; Ishikawa, Kouta; Akaike, Hiroyuki; Fujimaki, Akira

2015-04-01

339

Flow Visualization of Density in a Cryogenic Wind Tunnel Using Planar Rayleigh and Raman Scattering  

NASA Technical Reports Server (NTRS)

Using a pulsed Nd:YAG laser (532 nm) and a gated, intensified charge-coupled device, planar Rayleigh and Raman scattering techniques have been used to visualize the unseeded Mach 0.2 flow density in a 0.3-meter transonic cryogenic wind tunnel. Detection limits are determined for density measurements by using both unseeded Rayleigh and Raman (N2 vibrational) methods. Seeding with CO2 improved the Rayleigh flow visualization at temperatures below 150 K. The seeded Rayleigh version was used to demonstrate the observation of transient flow features in a separated boundary layer region, which was excited with an oscillatory jet. Finally, a significant degradation of the laser light sheet, in this cryogenic facility, is discussed.

Herring, Gregory C.; Shirinzadeh, Behrooz

2002-01-01

340

Development and test of two flexible cryogenic heat pipes. [for spaceborne instrument cooling  

NASA Technical Reports Server (NTRS)

Results are presented for a comprehensive test program directed toward determining the physical and thermal performance of two flexible cryogenic heat pipes that can provide a highly efficient thermal link between a detector and a space radiator or other cooling system in spacecraft applications. A 100-200 K high-power heat pipe is tested with methane at 100-140 K while a 15-100 K low-temperature pipe is designed for operation with nitrogen and oxygen and is optimized for oxygen in the range 75-90 K. Parametric performance and design tradeoff studies are carried out to determine the optimum geometry and materials for the container and wicking systems. A spiral multiwrap wick in conjunction with braided bellows appears to be a workable solution to the problem of developing highly flexible heat transport devices for cryogenic applications.

Wright, J. P.; Brennan, P. J.; Mccreight, C. R.

1976-01-01

341

Cryogenic small-signal conversion with relaxation oscillations in Josephson junctions  

E-print Network

Broadband detection of small electronic signals from cryogenic devices, with the option of simple implementation for multiplexing, is often a highly desired, although non-trivial task. We investigate and demonstrate a small-signal analog-to-frequency conversion system based on relaxation oscillations in a single Josephson junction. Operation and stability conditions are derived, with special emphasis on noise analysis, showing the dominant noise sources to originate from fluctuation processes in the junction. At optimum conditions the circuit is found to deliver excellent noise performance over a broad dynamic range. Our simple models successfully apply within the regime of classical Josephson junction and circuit dynamics, which we confirm by experimental results. A discussion on possible applications includes a measurement of the response to a cryogenic radiation detector.

Furlan, M

2006-01-01

342

Test Results of Selected Commercial DC/DC Converters under Cryogenic Temperatures - A Digest  

NASA Technical Reports Server (NTRS)

DC/DC converters are widely used in space power systems in the areas of power management and distribution, signal conditioning, and motor control. Design of DC/DC converters to survive cryogenic temperatures will improve the power system performance, simplify design, and reduce development and launch costs. In this work, the performance of nine COTS modular, low-tomedium power DC/DC converters was investigated under cryogenic temperatures. The converters were evaluated in terms of their output regulation, efficiency, and input and output currents. At a given temperature, these properties were obtained at various input voltages and at different load levels. A summary on the performance of the tested converters was given. More comprehensive testing and in-depth analysis of performance under long-term exposure to extreme temperatures are deemed necessary to establish the suitability of these and other devices for use in the harsh environment of space exploration missions.

Patterson, Richard; Hammoud, Ahmad

2010-01-01

343

Design and Testing of a Cryogenic Capillary Pumped Loop Flight Experiment  

NASA Technical Reports Server (NTRS)

This paper details the flight configuration and pre-flight performance test results of the fifth generation cryogenic capillary pumped loop (CCPL-5). This device will fly on STS-95 in October 1998 as part of the CRYOTSU Flight Experiment. This flight represents the first in-space demonstration of a CCPL; a miniaturized two-phase fluid circulator for thermally linking cryogenic components. CCPL-5 utilizes N2 as the working fluid and has a practical operating range of 75-110 K. Test results indicate that CCPL-5, which weighs about 200 grams, can transport over 10 W of cooling a distance of 0.25 m (or more) with less than a 5 K temperature drop.

Bugby, David C.; Kroliczek, Edward J.; Ku, Jentung; Swanson, Ted; Tomlinson, B. J.; Davis, Thomas M.; Baumann, Jane; Cullimore, Brent

1998-01-01

344

Thales Cryogenics rotary cryocoolers for HOT applications  

NASA Astrophysics Data System (ADS)

Thales Cryogenics has an extensive background in delivering reliable linear and rotary coolers for military, civil and space programs. Recent work carried out at detector level enable to consider a higher operation temperature for the cooled detectors. This has a direct impact on the cooling power required to the cryocooler. In continuation of the work presented last year, Thales cryogenics has studied the operation and optimization of the rotary cryocoolers at high cold regulation temperature. In this paper, the performances of the Thales Cryogenics rotary cryocoolers at elevated cold regulation temperature will be presented. From these results, some trade-offs can be made to combine correct operation of the cryocooler on all the ambient operational range and maximum efficiency of the cryocooler. These trade-offs and the impact on MTTF of elevated cold regulation temperature will be presented and discussed. In correlation with the increase of the cold operation temperature, the cryocooler input power is significantly decreased. As a consequence, the cooler drive electronics own consumption becomes relatively important and must be reduced in order to minimize global input power to the cooling function (cryocooler and cooler drive electronics). Thales Cryogenics has developed a new drive electronics optimized for low input power requirements. In parallel, improvements on RM1 and RM2 cryocoolers have been defined and implemented. The main impacts on performances of these new designs will be presented. Thales cryogenics is now able to propose an efficient cooling function for application requiring a high cold regulation temperature including a range of tuned rotary coolers.

Martin, Jean-Yves; Cauquil, Jean-Marc; Benschop, Tonny; Freche, Sébastien

2012-06-01

345

Cryogenic systems for the large deployable reflector  

NASA Technical Reports Server (NTRS)

There are five technologies which may have application for Large Deployable Reflector (LDR), one passive and four active. In order of maturity, they are passive stored cryogen systems, and mechanical, sorption, magnetic, and pulse-tube refrigerators. In addition, deep space radiators will be required to reject the heat of the active systems, and may be useful as auxiliary coolers for the stored cryogen systems. Hybrid combinations of these technologies may well be more efficient than any one alone, and extensive system studies will be required to determine the best trade-offs. Stored cryogen systems were flown on a number of missions. The systems are capable of meeting the temperature requirements of LDR. The size and weight of stored cryogen systems are proportional to heat load and, as a result, are applicable only if the low-temperature heat load can be kept small. Systems using chemisorption and physical adsorption for compressors and pumps have received considerable attention in the past few years. Systems based on adiabatic demagnetization of paramagnetic salts were used for refrigeration for many years. Pulse-tube refrigerators were recently proposed which show relatively high efficiency for temperatures in the 60 to 80 K range. The instrument heat loads and operating temperatures are critical to the selection and design of the cryogenic system. Every effort should be made to minimize heat loads, raise operating temperatures, and to define these precisely. No one technology is now ready for application to LDR. Substantial development efforts are underway in all of the technologies and should be monitored and advocated. Magnetic and pulse-tube refrigerators have high potential.

Mason, Peter V.

1988-01-01

346

The Nuclear Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

Nuclear Thermal Propulsion (NTP) development efforts in the United States have demonstrated the technical viability and performance potential of NTP systems. For example, Project Rover (1955 - 1973) completed 22 high power rocket reactor tests. Peak performances included operating at an average hydrogen exhaust temperature of 2550 K and a peak fuel power density of 5200 MW/m3 (Pewee test), operating at a thrust of 930 kN (Phoebus-2A test), and operating for 62.7 minutes in a single burn (NRX-A6 test). Results from Project Rover indicated that an NTP system with a high thrust-to-weight ratio and a specific impulse greater than 900 s would be feasible. Excellent results were also obtained by the former Soviet Union. Although historical programs had promising results, many factors would affect the development of a 21st century nuclear thermal rocket (NTR). Test facilities built in the US during Project Rover no longer exist. However, advances in analytical techniques, the ability to utilize or adapt existing facilities and infrastructure, and the ability to develop a limited number of new test facilities may enable affordable development, qualification, and utilization of a Nuclear Cryogenic Propulsion Stage (NCPS). Bead-loaded graphite fuel was utilized throughout the Rover/NERVA program, and coated graphite composite fuel (tested in the Nuclear Furnace) and cermet fuel both show potential for even higher performance than that demonstrated in the Rover/NERVA engine tests.. NASA's NCPS project was initiated in October, 2011, with the goal of assessing the affordability and viability of an NCPS. FY 2014 activities are focused on fabrication and test (non-nuclear) of both coated graphite composite fuel elements and cermet fuel elements. Additional activities include developing a pre-conceptual design of the NCPS stage and evaluating affordable strategies for NCPS development, qualification, and utilization. NCPS stage designs are focused on supporting human Mars missions. The NCPS is being designed to readily integrate with the Space Launch System (SLS). A wide range of strategies for enabling affordable NCPS development, qualification, and utilization should be considered. These include multiple test and demonstration strategies (both ground and in-space), multiple potential test sites, and multiple engine designs. Two potential NCPS fuels are currently under consideration - coated graphite composite fuel and tungsten cermet fuel. During 2014 a representative, partial length (approximately 16") coated graphite composite fuel element with prototypic depleted uranium loading is being fabricated at Oak Ridge National Laboratory (ORNL). In addition, a representative, partial length (approximately 16") cermet fuel element with prototypic depleted uranium loading is being fabricated at Marshall Space Flight Center (MSFC). During the development process small samples (approximately 3" length) will be tested in the Compact Fuel Element Environmental Tester (CFEET) at high temperature (approximately 2800 K) in a hydrogen environment to help ensure that basic fuel design and manufacturing process are adequate and have been performed correctly. Once designs and processes have been developed, longer fuel element segments will be fabricated and tested in the Nuclear Thermal Rocket Element Environmental Simulator (NTREE) at high temperature (approximately 2800 K) and in flowing hydrogen.

Houts, Michael G.; Kim, Tony; Emrich, William J.; Hickman, Robert R.; Broadway, Jeramie W.; Gerrish, Harold P.; Belvin, Anthony D.; Borowski, Stanley K.; Scott, John H.

2014-01-01

347

Ground-Based Investigations with the Cryogenic Hydrogen Maser  

NASA Technical Reports Server (NTRS)

The cryogenic hydrogen maser (CHM) developed at the Smithsonian Astrophysical Observatory (SAO) was designed to be functionally similar to SAO room temperature hydrogen masers with appropriate modifications made for operation at cryogenic temperatures. A schematic of the SAO CHM is shown in Figure 1, and a description of this device and its operation follows. A beam of molecular hydrogen is dissociated into atoms at room temperature. The resultant beam of atomic hydrogen is then cooled, magnetically state selected, and focused into a quartz storage bulb centered inside of a microwave cavity resonant with the hydrogen hyperfine transition at 1420 MHz. The quartz storage bulb is coated with a superfluid He-4 film, and both the bulb and cavity are maintained near 0.5 K. The maser signal is coupled out inductively and carried to room temperature via semi-rigid coaxial cable. After passing through a room temperature isolator and preamp, the maser signal is detected with a low-noise heterodyne receiver as used in the room temperature SAO hydrogen masers. The maser temperature is lowered to 0.5 K using a recirculating He-3 refrigerator. This refrigerator consists of several cooling stages: a liquid nitrogen stage at 77 K, a liquid 4He bath at 4.2 K, a pumped He-4 pot at approximately 1.7 K, and the pumped, recirculating He-3 stage at 0.5 K. The atomic hydrogen beam, state selector, storage bulb and cavity are all connected inside a single, maser vacuum chamber (MVC). This space is pumped out from below by a turbo pump. Above the MVC, an inlet to the space allows for the input of flowing superfluid 4He film. External to the MVC is a second, outer vacuum chamber (OVC), maintained for operation of the cryostat and also pumped by a turbo pump. Inside the OVC, there is radiation shielding at 77 K and 1.7 K.

Walsworth, Ronald L.; Mattison, Edward; Vessot, Robert F. C.

2003-01-01

348

Cryogenic measurements of aerojet GaAs n-JFETs  

NASA Technical Reports Server (NTRS)

The spectral noise characteristics of Aerojet GaAs n-JFETs have been investigated down to liquid helium temperatures. Voltage noise characterization was performed with the FET in 1) the floating gate mode, 2) the grounded gate mode to determine the lowest noise readings possible and 3) with an extrinsic silicon photodetector at various detector bias voltages, to determine optimum operating conditions. Current noise characterization was measured at the drain in the temperature range 300 to 77 K. Device design and MBE processing are described. Static I-V characterization is done at 300, 77 and 6 K. The measurements indicate that the Aerojet GaAs n-JFET is a quiet and stable device at liquid helium temperatures. Hence, it can be considered as a readout line driver or infrared detector preamplifier as well as a host of other cryogenic applications. Its noise performance is superior to that of Si MOSFETs operating at liquid helium temperatures, and is equal to the best Si n-JFETs operating at 300 K.

Goebel, John H.; Weber, Theodore T.; Van Rheenen, Arthur D.; Jostad, Leon; Kim, Joo-Young; Gable, Ben

1992-01-01

349

Liquid Oxygen/Liquid Methane Propulsion and Cryogenic Advanced Development  

NASA Technical Reports Server (NTRS)

Exploration Systems Architecture Study conducted by NASA in 2005 identified the liquid oxygen (LOx)/liquid methane (LCH4) propellant combination as a prime candidate for the Crew Exploration Vehicle Service Module propulsion and for later use for ascent stage propulsion of the lunar lander. Both the Crew Exploration Vehicle and Lunar Lander were part the Constellation architecture, which had the objective to provide global sustained lunar human exploration capability. From late 2005 through the end of 2010, NASA and industry matured advanced development designs for many components that could be employed in relatively high thrust, high delta velocity, pressure fed propulsion systems for these two applications. The major investments were in main engines, reaction control engines, and the devices needed for cryogenic fluid management such as screens, propellant management devices, thermodynamic vents, and mass gauges. Engine and thruster developments also included advanced high reliability low mass igniters. Extensive tests were successfully conducted for all of these elements. For the thrusters and engines, testing included sea level and altitude conditions. This advanced development provides a mature technology base for future liquid oxygen/liquid methane pressure fed space propulsion systems. This paper documents the design and test efforts along with resulting hardware and test results.

Klem, Mark D.; Smith, Timothy D.; Wadel, Mary F.; Meyer, Michael L.; Free, James M.; Cikanek, Harry A., III

2011-01-01

350

Status of the Cryogen-Free Cryogenic System for the CUORE Experiment  

NASA Astrophysics Data System (ADS)

The CUORE detector will be made of 988 TeO2 crystals and will need a base temperature lower than 10 mK in order to meet the performance specifications. To cool the CUORE detector a large cryogen-free cryostat with five pulse tubes and one specially designed high-power dilution refrigerator has been designed. The detector assembly has a total mass of about 1.5 ton and uses a vibration decoupling suspension system. Because of the stringent requirements regarding radioactivity, about 12 tons of lead shielding need to be cooled to 4 K and below, and only a limited number of construction materials are acceptable. The eight retractable radioactive sources for detector calibration and about 2600 signal wires add further complexity to the system. The many stringent and contrasting requirements together with the overall large size made the design of the CUORE cryogenic system a real mechanical and cryogenic engineering challenge. The cryogenic system is expected to be fully operational in the Gran Sasso Laboratory in July 2013. We report here about the current status of the cryogenic system construction, which has started about one year.

Nucciotti, A.; Alessandria, F.; Ameri, M.; Bucci, C.; Bersani, A.; Canonica, L.; Cereseto, R.; Ceruti, G.; Cremonesi, O.; Dally, A.; Datskov, V.; Dossena, S.; Ejzak, L.; Faverzani, M.; Ferri, E.; Franceschi, A.; Gregerson, G.; Heeger, K.; Ligi, C.; Napolitano, T.; Orlandi, D.; Sisti, M.; Taffarello, L.; Tatananni, L.; Wise, T.; Woodcraft, A.

2011-11-01

351

Optimized Heat Interception for Cryogen Tank Support  

NASA Technical Reports Server (NTRS)

We consider means for using the cooling available in boil-off gas to intercept heat conducted through the support structure of a cryogen tank. A one-dimensional model of the structure coupled to a gas stream gives an analytical expression for heat leak in terms of flow rate for temperature independent-properties and laminar flow. A numerical model has been developed for heat transfer on a thin cylindrical tube with an attached vent line. The model is used to determine the vent path layout that will minimize heat flow into the cryogen tank. The results are useful for a number of applications, but the one of interest in this study is the minimization of the boil-off in large cryopropellant tanks in low Earth and low lunar orbit.

Canavan, Edgar R.; Miller, F. K.

2007-01-01

352

Cryogenic hydrogen circulation system of neutron source  

SciTech Connect

Cold neutron sources of reactors and spallation neutron sources are classic high flux neutron sources in operation all over the world. Cryogenic fluids such as supercritical or supercooled hydrogen are commonly selected as a moderator to absorb the nuclear heating from proton beams. By comparing supercritical hydrogen circulation systems and supercooled hydrogen circulation systems, the merits and drawbacks in both systems are summarized. When supercritical hydrogen circulates as the moderator, severe pressure fluctuations caused by temperature changes will occur. The pressure control system used to balance the system pressure, which consists of a heater as an active controller for thermal compensation and an accumulator as a passive volume controller, is preliminarily studied. The results may provide guidelines for design and operation of other cryogenic hydrogen system for neutron sources under construction.

Qiu, Y. N. [Institute of Physics and Chemistry, Chinese Academy of Sciences, BJ100190 China and University of Chinese Academy of Sciences, Chinese Academy of Sciences, BJ100049 (China); Hu, Z. J.; Wu, J. H.; Li, Q.; Zhang, Y. [Institute of Physics and Chemistry, Chinese Academy of Sciences, BJ100190 (China); Zhang, P. [School of Energy and Power Engineering, HuaZhong University of Science and Technology, WH430074 (China); Wang, G. P. [Institute of High Energy Physics, Chinese Academy of Sciences, BJ100049 (China)

2014-01-29

353

D0 Cryogenic In-Line Filters  

SciTech Connect

The DO cryogenic system utilizes liquid argon (serving as the detector ionizing medium) and liquid nitrogen (refrigerant for the argon). In order to keep these fluids pure and minimize the likelihood of plugged instrumentation due to contamination, in-line filters will be installed on the following lines (see Cryogenic Flow Diagram, drawing 3740-ME-222394): 445LN, 412LN, 447LA, 427LA. and 422GA. The lines referred to by these labels are argon dewar LN2 supply, cryostat LN2 supply, LAr dewar fill/drain line, cryostat LAr fill/drain line, and dewar-to-cryostat argon gas line, respectively. Five filters are required. As of this writing, one has been built and tested. The others are to be identical in concept and construction.

Fuerst, J.D.; /Fermilab

1988-10-04

354

IRAS cryogenic system flight performance report  

NASA Technical Reports Server (NTRS)

It is pointed out that the Infrared Astronomical Satellite (IRAS) is the first telescope to perform observations in the far infrared from orbit. IRAS was launched on January 25, 1983 into a 900 km orbit. The use of the first large superfluid helium dewar in space makes it possible to provide a 2 K telescope environment for an anticipated period of one year. A description of the cryogenic system of IRAS is presented, taking into account the superfluid helium tank, the insulation system, the vacuum shell, the aperture cover, and the fluid management system. The dynamic performance of the cryogenic system is considered along with aspects of prelaunch preparations. Details of flight performance are also discussed, giving attention to transient performance, and steady state performance.

Urbach, A. R.; Mason, P. V.

1984-01-01

355

Absorber Materials at Room and Cryogenic Temperatures  

SciTech Connect

We recently reported on investigations of RF absorber materials at cryogenic temperatures conducted at Jefferson Laboratory (JLab). The work was initiated to find a replacement material for the 2 Kelvin low power waveguide Higher Order Mode (HOM) absorbers employed within the original cavity cryomodules of the Continuous Electron Beam Accelerator Facility (CEBAF). This effort eventually led to suitable candidates as reported in this paper. Furthermore, though constrained by small funds for labor and resources, we have analyzed a variety of lossy ceramic materials, several of which could be usable as HOM absorbers for both normal conducting and superconducting RF structures, e.g. as loads in cavity waveguides and beam tubes either at room or cryogenic temperatures and, depending on cooling measures, low to high operational power levels.

F. Marhauser, T.S. Elliott, A.T. Wu, E.P. Chojnacki, E. Savrun

2011-09-01

356

Design concepts for the ASTROMAG cryogenic system  

NASA Technical Reports Server (NTRS)

Described is a proposed cryogenic system used to cool the superconducting magnet for the Space Station based ASTROMAG Particle Astrophysics Facility. This 2-meter diameter superconducting magnet will be cooled using stored helium II. The paper presents a liquid helium storage concept which would permit cryogenic lifetimes of up to 3 years between refills. It is proposed that the superconducting coil be cooled using superfluid helium pumped by the thermomechanical effect. It is also proposed that the storage tank be resupplied with helium in orbit. A method for charging and discharging the magnet with minimum helium loss using split gas-cooled leads is discussed. A proposal to use a Stirling cycle cryocooler to extend the storage life of the cryostat will also be presented.

Green, M. A.; Castles, S.

1987-01-01

357

Design concepts for the ASTROMAG cryogenic system  

NASA Technical Reports Server (NTRS)

Described is a proposed cryogenic system used to cool the superconducting magnet for the Space Station based ASTROMAG Particle Astrophysics Facility. This 2-meter diameter superconducting magnet will be cooled using stored helium II. The paper presents a liquid helium storage concept which would permit cryogenic lifetimes of up to 3 years between refills. It is proposed that the superconducting coil be cooled using superfluid helium pumped by the thermomechanical effect. It is also proposed that the storage tank be resupplied with helium in orbit. A method for charging and discharging the magnet with minimum helium loss using split gas-cooled leads is discussed. A proposal to use a Stirling cycle cryocooler to extend the storage life of the cryostat will also be presented.

Green, M. A.; Castles, S.

1988-01-01

358

Cryogenic cooling for high power laser amplifiers  

NASA Astrophysics Data System (ADS)

Using DPSSL (Diode Pumped Solid State Lasers) as pumping technology, PW-class lasers with enhanced repetition rates are developed. Each of the Yb YAG amplifiers will be diode-pumped at a wavelength of 940 nm. This is a prerequisite for achieving high repetition rates (light amplification duration 1 millisecond and repetition rate 10 Hz). The efficiency of DPSSL is inversely proportional to the temperature, for this reason the slab amplifier have to be cooled at a temperature in the range of 100 K-170 K with a heat flux of 1 MW*m-2. This paper describes the thermo-mechanical analysis for the design of the amplification laser head, presents a preliminary proposal for the required cryogenic cooling system and finally outlines the gain of cryogenic operation for the efficiency of high pulsed laser.

Perin, J. P.; Millet, F.; Divoky, M.; Rus, B.

2013-11-01

359

Cryogenic fluid management (base R/T): Cryogenic fluid systems, Cryogenic Orbital Nitrogen Experiment (CONE), Cryogenic Orbital Hydrogen Experiment (COHE). (Transportation focused technology)  

NASA Technical Reports Server (NTRS)

The topics presented are covered in viewgraph form. The concluded remarks are: (1) advanced cryogenic fluid systems technology is enhancing or enabling to all known transportation scenarios for space exploration; (2) an integrated/coordinated program involving LeRC/MSFC has been formulated to address all known CFM needs - new needs should they develop, can be accommodated within available skills/facilities; (3) all required/experienced personnel and facilities are finally in place - data from initial ground-based experiments is being collected and analyzed - small scale STS experiments are nearing flight - program is beginning to yield significant results; (4) future proposed funding to primarily come from two sources; and (5) cryogenic fluid experimentation is essential to provide required technology and assure implementation in future NASA missions.

Symons, Pat

1991-01-01

360

Cryogenic laser fusion target material design considerations  

NASA Astrophysics Data System (ADS)

Laser fusion target designs exhibit improved performance when the fusion fuel, a deuterium-tritium (DT) mixture, is frozen into a uniform, solid shell. The formation of such a shell requires rapid isothermal cooling of the target to cryogenic temperatures. The cooling rate must be sufficiently fast to prevent significant, gravitationally driven downward flow of the DT as it passes from the gaseous through the liquid state. Because it is not possible to measure the uniformity of a solid DT layer in opaque, multishell targets, we have modeled such targets to calculate the cooling rate and, hence, the expected thickness uniformity of the DT shell. The presented results provide target designers with practical guidelines for the selection of materials and configurations, which will assist in the fabrication of high-quality cryogenic targets.

Miller, J. R.; Fries, R. J.; Press, W. J.

1979-12-01

361

Alignment Stage for a Cryogenic Dilatometer  

NASA Technical Reports Server (NTRS)

A three-degree-of-freedom alignment stage has been designed and built for use in a cryogenic dilatometer that is used to measure thermal strains. The alignment stage enables precise adjustments of the positions and orientations of optical components to be used in the measurements and, once adjustments have been completed, keeps the components precisely aligned during cryogenic-dilatometer operations that can last as long as several days. The alignment stage includes a case, a circular tilt/tip platform, and a variety of flexural couplings between the case and the platform, all machined from a single block of the low-thermal-expansion iron/nickel alloy Invar, in order to minimize effects of temperature gradients and to obtain couplings that are free of stiction and friction. There are three sets of flexural couplings clocked at equal angles of 120 degrees around the platform, constituting a three-point kinematic support system.

Dudik, Matthew; Moore, Donald

2005-01-01

362

Cryogenic Magnetic Bearing Test Facility (CMBTF)  

NASA Technical Reports Server (NTRS)

The Cryogenic Magnetic Bearing Test Facility (CMBTF) was designed and built to evaluate compact, lightweight magnetic bearings for use in the SSME's (space shuttle main engine) liquid oxygen and liquid hydrogen turbopumps. State of the art and tradeoff studies were conducted which indicated that a hybrid permanent magnet bias homopolar magnetic bearing design would be smaller, lighter, and much more efficient than conventional industrial bearings. A test bearing of this type was designed for the test rig for use at both room temperature and cryogenic temperature (-320 F). The bearing was fabricated from state-of-the-art materials and incorporated into the CMBTF. Testing at room temperature was accomplished at Avcon's facility. These preliminary tests indicated that this magnetic bearing is a feasible alternative to older bearing technologies. Analyses showed that the hybrid magnetic bearing is one-third the weight, considerably smaller, and uses less power than previous generations of magnetic bearings.

1992-01-01

363

Cryogenic helium 2 systems for space applications  

NASA Technical Reports Server (NTRS)

Two cryogenic systems are described which will provide cooling for experiments to be flown on Spacelab 2 in the early 1980's. The first system cools a scanning infrared telescope by the transfer of cold helium gas from a separate superfluid helium storage dewar. The flexible design permits the helium storage dewar and transfer assembly to be designed independent of the infrared experiment. Where possible, modified commerical apparatus is used. The second cryogenic system utilizes a specially designed superfluid dewar in which a superfluid helium experiment chamber is immersed. Each dewar system employs a porous plug as a phase separator to hold the liquid helium within the dewar and provide cold gas to a vent line. To maintain the low vapor pressure of the superfluid, each system requires nearly continuous prelaunch vacuum pump service, and each will vent to space during the Spacelab 2 flight.

Urban, E.; Katz, L.; Hendricks, J.; Karr, G.

1978-01-01

364

Optimized Heat Interception for Cryogen Tank Support  

NASA Astrophysics Data System (ADS)

We consider means for using the cooling available in boil-off gas to intercept heat conducted through the support structure of a cryogen tank. A one-dimensional model of the structure coupled to a gas stream gives an analytical expression for heat leak in terms of flow rate for temperature independent-properties and laminar flow. A numerical model has been developed for heat transfer on a thin cylindrical tube with an attached vent line. The model is used to determine the vent path layout that will minimize heat flow into the cryogen tank. The results are useful for a number of applications, but the one of interest in this study is the minimization of the boil-off in large cryopropellant tanks in low Earth and low lunar orbit.

Canavan, E. R.; Miller, F. K.

2008-03-01

365

Test of a cryogenic helium pump  

SciTech Connect

The design of a cryogenic helium pump for circulating liquid helium in a magnet and the design of a test loop for measuring the pump performance in terms of mass flow vs pump head at various pump speeds are described. A commercial cryogenic helium pump was tested successfully. Despite flaws in the demountable connections, the piston pump itself has performed satisfactorily. A helium pump of this type is suitable for the use of flowing supercritical helium through Internally Cooled Superconductor (ICS) magnets. It has pumped supercritical helium up to 7.5 atm with a pump head up to 2.8 atm. The maximum mass flow rate obtained was about 16 g/s. Performance of the pump was degraded at lower pumping speeds. (LCL)

Lue, J.W.; Miller, J.R.; Walstrom, P.L.; Herz, W.

1981-01-01

366

Ethane rejection from existing cryogenic plants  

SciTech Connect

Natural gas cryogenic expander plants are designed for maximum economic ethane recovery. The percentage of ethane recovered depends on various factors, such as temperature, pressure, and composition of the inlet gas; demethanizer tower pressure; type of cryogenic process; and whether supplemental refrigeration is used. Plants now in service typically recover in the range of 70 to 80% ethane. However, with the high cost of gas, it may not be profitable to operate at a high ethane recovery; it may be more economical to operate at high propane recovery and reject as much ethane as possible. How existing plants can be operated to reject ethane, and what can be expected in the way of propane recovery are discussed.

Schnack, H.L.

1982-01-01

367

Cryogenic hydrogen circulation system of neutron source  

NASA Astrophysics Data System (ADS)

Cold neutron sources of reactors and spallation neutron sources are classic high flux neutron sources in operation all over the world. Cryogenic fluids such as supercritical or supercooled hydrogen are commonly selected as a moderator to absorb the nuclear heating from proton beams. By comparing supercritical hydrogen circulation systems and supercooled hydrogen circulation systems, the merits and drawbacks in both systems are summarized. When supercritical hydrogen circulates as the moderator, severe pressure fluctuations caused by temperature changes will occur. The pressure control system used to balance the system pressure, which consists of a heater as an active controller for thermal compensation and an accumulator as a passive volume controller, is preliminarily studied. The results may provide guidelines for design and operation of other cryogenic hydrogen system for neutron sources under construction.

Qiu, Y. N.; Hu, Z. J.; Wu, J. H.; Li, Q.; Zhang, Y.; Zhang, P.; Wang, G. P.

2014-01-01

368

Cryogen free sample environment for neutron scattering experiments at ISIS  

NASA Astrophysics Data System (ADS)

Most neutron facilities have a fleet of cryostats providing low temperature and high magnetic fields for sample environment. This large scale usage of cryogenic equipment requires significant resources and can create a number of problems including health and safety issues and the considerable cost of the required cryogens. The last problem has become more significant due to the increasing costs of liquid helium caused by global helium supply problems. The ISIS facility has an internal development programme intended to gradually substitute all conventional cryogenic systems with cryogen free systems preferably based on the pulse tube refrigerator. The programme includes a number of development projects which are aiming to deliver a range of cryogen free equipment including a top-loading 1.5 K cryostat, superconducting magnets in re-condensing cryostats and cryogen free dilution refrigerators. Here we are going to describe the design of these systems and discuss the results of prototype testing.

Kirichek, O.; Down, R. B. E.; Keeping, J.; Evans, B.; Bowden, Z. A.

2012-02-01

369

Feasibility study for the Cryogenic Orbital Nitrogen Experiment (CONE)  

NASA Technical Reports Server (NTRS)

An improved understanding of low gravity subcritical cryogenic fluid behavior is critical for the continued development of space based systems. Although early experimental programs provided some fundamental understanding of zero gravity cryogenic fluid behavior, more extensive flight data are required to design space based cryogenic liquid storage and transfer systems with confidence. As NASA's mission concepts evolve, the demand for optimized in-space cryogenic systems is increasing. Cryogenic Orbital Nitrogen Experiment (CONE) is an attached shuttle payload experiment designed to address major technological issues associated with on-orbit storage and supply of cryogenic liquids. During its 7 day mission, CONE will conduct experiments and technology demonstrations in active and passive pressure control, stratification and mixing, liquid delivery and expulsion efficiency, and pressurant bottle recharge. These experiments, conducted with liquid nitrogen as the test fluid, will substantially extend the existing low gravity fluid data base and will provide future system designers with vital performance data from an orbital environment.

Bell, R. S.; Crouch, M. A.; Hanna, G. J.; Cady, E. C.; Meserole, J. S.

1991-01-01

370

Value for controlling flow of cryogenic fluid  

DOEpatents

A valve is provided for accurately controlling the flow of cryogenic fluids such as liquid nitrogen. The valve comprises a combination of disc and needle valves affixed to a valve stem in such a manner that the disc and needle are free to rotate about the stem, but are constrained in lateral and vertical movements. This arrangement provides accurate and precise fluid flow control and positive fluid isolation.

Knapp, Philip A. (Moore, ID)

1996-01-01

371

Cryogenic System for the Spallation Neutron Source  

Microsoft Academic Search

The Spallation Neutron Source (SNS) is a neutron-scattering facility being built at Oak Ridge, TN for the US Department of Energy. The SNS accelerator linac consists of superconducting radio-frequency (SRF) cavities in cryostats (cryomodules). The linac cryomodules are cooled to 2.1 K by a 2300 watt cryogenic refrigeration system. As an SNS partner laboratory, Jefferson Lab is responsible for the

D. Arenius; W. Chronis; J. Creel; K. Dixon; V. Ganni; P. Knudsen

2004-01-01

372

Method and apparatus for producing cryogenic targets  

SciTech Connect

An improved method and apparatus are given for producing cryogenic inertially driven fusion targets in the fast isothermal freezing (FIF) method. Improved coupling efficiency and greater availability of volume near the target for diagnostic purposes and for fusion driver beam propagation result. Other embodiments include a new electrical switch and a new explosive detonator, all embodiments making use of a purposeful heating by means of optical fibers.

Murphy, J.T.; Miller, J.R.

1981-08-28

373

Active Control of Cryogenic Propellants in Space  

NASA Technical Reports Server (NTRS)

A new era of space exploration is being planned. Exploration architectures under consideration require the long term storage of cryogenic propellants in space. This requires development of active control systems to mitigate the effect of heat leak. This work summarizes current state of the art, proposes operational design strategies and presents options for future architectures. Scaling and integration of active systems will be estimated. Ideal long range spacecraft systems will be proposed with Exploration architecture benefits considered.

Notardonato, William

2011-01-01

374

Cryogenic Boil-Off Reduction System  

NASA Astrophysics Data System (ADS)

A computational model of the cryogenic boil-off reduction system being developed by NASA as part of the Cryogenic Propellant Storage and Transfer technology maturation project has been applied to a range of propellant storage tanks sizes for high-performing in-space cryogenic propulsion applications. This effort focuses on the scaling of multi-layer insulation (MLI), cryocoolers, broad area cooling shields, radiators, solar arrays, and tanks for liquid hydrogen propellant storage tanks ranging from 2 to 10 m in diameter. Component scaling equations were incorporated into the Cryogenic Analysis Tool, a spreadsheet-based tool used to perform system-level parametric studies. The primary addition to the evolution of this updated tool is the integration of a scaling method for reverse turbo-Brayton cycle cryocoolers, as well as the development and inclusion of Self-Supporting Multi-Layer Insulation. Mass, power, and sizing relationships are traded parametrically to establish the appropriate loiter period beyond which this boil-off reduction system application reduces mass. The projected benefit compares passive thermal control to active thermal control, where active thermal control is evaluated for reduced boil-off with a 90 K shield, zero boil-off with a single heat interception stage at the tank wall, and zero boil-off with a second interception stage at a 90 K shield. Parametric studies show a benefit over passive storage at loiter durations under one month, in addition to showing a benefit for two-stage zero boil-off in terms of reducing power and mass as compared to single stage zero boil-off. Furthermore, active cooling reduces the effect of varied multi-layer insulation performance, which, historically, has been shown to be significant.

Plachta, David W.; Guzik, Monica C.

2014-03-01

375

Compensating For Shrinkage In A Cryogenic Seal  

NASA Technical Reports Server (NTRS)

Proposed design for seals in liquid-hydrogen plumbing eliminates leaks caused by contraction of seals at low operating temperature. Each seal consists of rubber, polytetrafluorethylene, or lead O-ring including hollow core filled with water. At temperature of liquid hydrogen, anomalous expansion of water keeps seal gland filled and leaktight despite shrinkage of surrounding O-ring material. Design also used in systems using cryogenic fluids other than liquid hydrogen.

Hill, Arnold E.

1993-01-01

376

Active control of cryogenic propellants in space  

NASA Astrophysics Data System (ADS)

A new era of space exploration is being planned. Exploration architectures under consideration require the long term storage of cryogenic propellants in space. This requires development of active control systems to mitigate the effect of heat leak. This work summarizes current state of the art, proposes operational design strategies and presents options for future architectures. Scaling and integration of active systems will be estimated. Ideal long range spacecraft systems will be proposed with exploration architecture benefits considered.

Notardonato, William

2012-04-01

377

CRYOGENIC FLUIDS IN NUCLEAR PROPULSION SYSTEMS  

Microsoft Academic Search

Nuclear rocket engines employ hydrogen, a cryogenic liquid, as a ;\\u000a propellant in order to obtain a system with a high specific impulse. Since ;\\u000a hydrogen is also an excellent moderator of neutrons, it provides a reactivity ;\\u000a contribution which must be taken into consideration in the design of a reactor ;\\u000a and in its programmed operation. The reactivity worth

R. S. Thurston; J. D. Balcomb; G. P. Watts; R. S. Pollock; A. R. Lyle

1963-01-01

378

Thin-film cryogenic current comparator  

Microsoft Academic Search

We analyze a thin-film cryogenic current comparator (CCC) intended to be used in ac measurements. Our analysis shows that by calibrating the dc ratio error of the thin-film CCC against a conventional CCC, it can be used up to 10 kHz as a sensitive and highly accurate current comparator. We have fabricated a practical 1:1 planar CCC integrated with a

H. Seppa; A. Satrapinski; M. Kiviranta; V. Virkki

1999-01-01

379

Cryogenic Treatment of Tool Materials: A Review  

Microsoft Academic Search

Cryogenic treatment (CT) of materials has shown significant improvement in their properties. Various advantages like increase in wear resistance, reduced residual stresses, increase in hardness, fatigue resistance, toughness imparted by transformation of retained austenite to martensite, precipitation of carbides, eta-carbide formation, perfect distributed\\/homogenous crystal structure, better thermal conductivity, and reduced chemical degradation. Moreover, this technology is an eco-friendly, nontoxic, and

Nirmal S. Kalsi; Rakesh Sehgal; Vishal S. Sharma

2010-01-01

380

Cryogenic adhesives and sealants: Abstracted publications  

NASA Technical Reports Server (NTRS)

Abstracts of primary documents containing original experimental data on the properties of adhesives and sealants at cryogenic temperatures are presented. The most important references mentioned in each document are cited. In addition, a brief annotation is given for documents considered secondary in nature, such as republications or variations of original reports, progress reports leading to final reports included as primary documents, and experimental data on adhesive properties at temperatures between about 130 K and room temperature.

Williamson, F. R.; Olien, N. A.

1977-01-01

381

Method and apparatus for producing cryogenic targets  

DOEpatents

An improved method and apparatus are given for producing cryogenic inertially driven fusion targets in the fast isothermal freezing (FIF) method. Improved coupling efficiency and greater availability of volume near the target for diagnostic purposes and for fusion driver beam propagation result. Other embodiments include a new electrical switch and a new explosive detonator, all embodiments making use of a purposeful heating by means of optical fibers. 6 figs.

Murphy, J.T.; Miller, J.R.

1984-08-07

382

Terrestrial Planet Finder cryogenic delay line development  

NASA Technical Reports Server (NTRS)

Delay lines provide the path-length compensation that makes the measurement of interference fringes possible. When used for nulling interferometry, the delay line must control path-lengths so that the null is stable and controlled throughout the measurement. We report on a low noise, low disturbance, and high bandwidth optical delay line capable of meeting the TPF interferometer optical path length control requirements at cryogenic temperatures.

Smythe, Robert F.; Swain, Mark R.; Alvarez-Salazar, Oscar; Moore, James D.

2004-01-01

383

Design, construction and cooling system performance of a prototype cryogenic stopping cell for the Super-FRS at FAIR  

NASA Astrophysics Data System (ADS)

A cryogenic stopping cell for stopping energetic radioactive ions and extracting them as a low energy beam was developed. This first ever cryogenically operated stopping cell serves as prototype device for the Low-Energy Branch of the Super-FRS at FAIR. The cell has a stopping volume that is 1 m long and 25 cm in diameter. Ions are guided by a DC field along the length of the stopping cell and by a combined RF and DC fields provided by an RF carpet at the exit-hole side. The ultra-high purity of the stopping gas required for optimum ion survival is reached by cryogenic operation. The design considerations and construction of the cryogenic stopping cell, as well as some performance characteristics, are described in detail. Special attention is given to the cryogenic aspects in the design and construction of the stopping cell and the cryocooler-based cooling system. The cooling system allows the operation of the stopping cell at any desired temperature between about 70 K and room temperature. The cooling system performance in realistic on-line conditions at the FRS Ion Catcher Facility at GSI is discussed. A temperature of 110 K at which efficient ion survival was observed is obtained after 10 h of cooling. A minimum temperature of the stopping gas of 72 K was reached. The expertise gained from the design, construction and performance of the prototype cryogenic stopping cell has allowed the development of a final version for the Low-Energy Branch of the Super-FRS to proceed.

Ranjan, M.; Dendooven, P.; Purushothaman, S.; Dickel, T.; Reiter, M. P.; Ayet, S.; Haettner, E.; Moore, I. D.; Kalantar-Nayestanaki, N.; Geissel, H.; Plaß, W. R.; Schäfer, D.; Scheidenberger, C.; Schreuder, F.; Timersma, H.; Van de Walle, J.; Weick, H.

2015-01-01

384

Properties and Processes for Cryogenic Refrigeration R. Radebaugh, P. Bradley, M. Lewis (838), J. Gary, and A. O'Gallagher (ITL)  

E-print Network

Properties and Processes for Cryogenic Refrigeration R. Radebaugh, P. Bradley, M. Lewis (838), J device company, we completed measurements on the performance of a simple pulse tube refrigerator with pulse tube refrigerators). Using a compressor with a piston-position sensor we were able to characterize

Magee, Joseph W.

385

Cryogenic operation of GaAs based multiplier chains to 400 GHz A. Maestrini, D. Pukala, F. Maiwald, E. Schlecht, G. Chattopadhyay, and I. Mehdi  

E-print Network

of frequencies will be described. Preliminary measurements at cryogenic temperatures done on individual multi advances in the fabrication of the circuits and planar devices has re- sulted in tremendous progress between the various diode parameters when one is designing for low-temperature high input-power appli

Chattopadhyay, Goutam

386

NTF: Soldering Technology Development for Cryogenics  

NASA Technical Reports Server (NTRS)

The advent of the National Transonic Facility (NTF) brought about a new application for an old joining method, soldering. Soldering for use at cryogenic temperatures requires that solders remain ductile and free from tin-pest (grey tin), have toughness to withstand aerodynamic loads associated with flight research, and maintain their surface finishes. Solders are used to attach 347 Stainless-Steel tubing in surface grooves of models. The solder must fill up the gap and metallurgically bound to the tubing and model. Cryogenic temperatures require that only specific materials for models can be used, including: Vasco Max 200 CVM, lescalloy A-286 Vac Arc, pH 13-8 Mo. Solders identified for testing at this time are: 50% Sn - 49.5% Pb - 0.5% Sb, 95% Sn - 5% Sb, 50% In 50% Pb, and 37.5% Sn - 37.5% Pb - 25% In. With these materials and solders, it is necessary to determine their solderability. After solderability is determined, tube/groove specimens are fabricated and stressed under cryogenic temperatures. Compatible solders are then used for acutual models.

Hall, E. T., Jr.

1985-01-01

387

Miniature thermo-electric cooled cryogenic pump  

DOEpatents

A miniature thermo-electric cooled cryogenic pump for removing residual water molecules from an inlet sample prior to sample analysis in a mass spectroscopy system, such as ion cyclotron resonance (ICR) mass spectroscopy. The cryogenic pump is a battery operated, low power (<1.6 watts) pump with a .DELTA.T=100.degree. C. characteristic. The pump operates under vacuum pressures of 5.times.10.sup.-4 Torr to ultra high vacuum (UHV) conditions in the range of 1.times.10.sup.-7 to 3.times.10.sup.-9 Torr and will typically remove partial pressure, 2.times.10.sup.-7 Torr, residual water vapor. The cryogenic pump basically consists of an inlet flange piece, a copper heat sink with a square internal bore, four two tier Peltier (TEC) chips, a copper low temperature square cross sectional tubulation, an electronic receptacle, and an exit flange piece, with the low temperature tubulation being retained in the heat sink at a bias angle of 5.degree., and with the TECs being positioned in parallel to each other with a positive potential being applied to the top tier thereof.

Keville, Robert F. (Valley Springs, CA)

1997-01-01

388

Miniature thermo-electric cooled cryogenic pump  

DOEpatents

A miniature thermo-electric cooled cryogenic pump is described for removing residual water molecules from an inlet sample prior to sample analysis in a mass spectroscopy system, such as ion cyclotron resonance (ICR) mass spectroscopy. The cryogenic pump is a battery operated, low power (<1.6 watts) pump with a {Delta}T=100 C characteristic. The pump operates under vacuum pressures of 5{times}10{sup {minus}4} Torr to ultra high vacuum (UHV) conditions in the range of 1{times}10{sup {minus}7} to 3{times}10{sup {minus}9} Torr and will typically remove partial pressure, 2{times}10{sup {minus}7} Torr, residual water vapor. The cryogenic pump basically consists of an inlet flange piece, a copper heat sink with a square internal bore, four two tier Peltier (TEC) chips, a copper low temperature square cross sectional tubulation, an electronic receptacle, and an exit flange piece, with the low temperature tubulation being retained in the heat sink at a bias angle of 5{degree}, and with the TECs being positioned in parallel to each other with a positive potential being applied to the top tier thereof. 2 figs.

Keville, R.F.

1997-11-18

389

Design Tool for Cryogenic Thermal Insulation Systems  

SciTech Connect

Thermal isolation of low-temperature systems from ambient environments is a constant issue faced by practitioners of cryogenics. For energy-efficient systems and processes to be realized, thermal insulation must be considered as an integrated system, not merely an add-on element. A design tool to determine the performance of insulation systems for comparative trade-off studies of different available material options was developed. The approach is to apply thermal analysis to standard shapes (plane walls, cylinders, spheres) that are relatively simple to characterize with a one-dimensional analytical or numerical model. The user describes the system hot and cold boundary geometry and the operating environment. Basic outputs such as heat load and temperature profiles are determined. The user can select from a built-in insulation material database or input user defined materials. Existing information has been combined with the new experimental thermal conductivity data produced by the Cryogenics Test Laboratory for cryogenic and vacuum environments, including high vacuum, soft vacuum, and no vacuum. Materials in the design tool include multilayer insulation, aerogel blankets, aerogel bulk-fill, foams, powders, composites, and other insulation system constructions. A comparison of the design tool to a specific composite thermal insulation system is given.

Demko, Jonathan A [ORNL] [ORNL; Fesmire, J. E. [NASA Kennedy Space Center, Kennedy Space Center, Florida] [NASA Kennedy Space Center, Kennedy Space Center, Florida; Augustynowicz, S. D. [Sierra Lobo Inc., Kennedy Space Center, Florida] [Sierra Lobo Inc., Kennedy Space Center, Florida

2008-01-01

390

Developing NDE Techniques for Large Cryogenic Tanks  

NASA Technical Reports Server (NTRS)

The Shuttle Program requires very large cryogenic ground storage tanks in which to store liquid oxygen and hydrogen. The existing Pads A and B Launch Complex-39 tanks, which will be passed onto future launch programs, are 45 years old and have received minimal refurbishment and only external inspections over the years. The majority of the structure is inaccessible without a full system drain of cryogenic liquid and granular insulation in the annular region. It was previously thought that there was a limit to the number of temperature cycles that the tanks could handle due to possible insulation compaction before undergoing a costly and time consuming complete overhaul; therefore the tanks were not drained and performance issues with these tanks, specifically the Pad B liquid hydrogen tank, were accepted. There is a needind an opportunity, as the Shuttle program ends and work to upgrade the launch pads progresses, to develop innovative non-destructive evaluation (NDE) techniques to analyze the current tanks. Techniques are desired that can aid in determining the extent of refurbishment required to keep the tanks in service for another 20+ years. A nondestructive technique would also be a significant aid in acceptance testing of new and refurbished tanks, saving significant time and money, if corrective actions can be taken before cryogen is introduced to the systems.

Parker, Don; Starr, Stan; Arens, Ellen

2011-01-01

391

Thermal Performance Testing Of Cryogenic Piping Systems  

NASA Technical Reports Server (NTRS)

Thermal performance measurement of piping systems under actual field conditions is important for space launch development and commercial industry. Knowledge of the true insulating effectiveness is needed in system design, development, and research activities. A new 18-meter-long test apparatus for cryogenic pipelines has been developed. Three different pipelines, rigid or flexible, can be tested simultaneously. Critical factors in heat leak measurements include eliminating heat transfer at end connections and obtaining proper liquid saturation condition. Effects due to variations in the external ambient conditions like wind, humidity, and solar radiation must be minimized. The static method of liquid nitrogen evaporation has been demonstrated, but the apparatus can be adapted for dynamic testing with cryogens, chilled water, or other working fluids. This technology is suited for the development of an industry standard test apparatus and method. Examples of the heat transfer data from testing commercially available pipelines are given. Prototype pipelines are currently being tested and evaluated at the Cryogenics Test Laboratory of NASA Kennedy Space Center.

Fesmire, J. E.; Augustynowicz, S. D.; Nagy, Z. F.

2003-01-01

392

Temperature Stratification in a Cryogenic Fuel Tank  

NASA Technical Reports Server (NTRS)

A reduced dynamical model describing temperature stratification effects driven by natural convection in a liquid hydrogen cryogenic fuel tank has been developed. It accounts for cryogenic propellant loading, storage, and unloading in the conditions of normal, increased, and micro- gravity. The model involves multiple horizontal control volumes in both liquid and ullage spaces. Temperature and velocity boundary layers at the tank walls are taken into account by using correlation relations. Heat exchange involving the tank wall is considered by means of the lumped-parameter method. By employing basic conservation laws, the model takes into consideration the major multi-phase mass and energy exchange processes involved, such as condensation-evaporation of the hydrogen, as well as flows of hydrogen liquid and vapor in the presence of pressurizing helium gas. The model involves a liquid hydrogen feed line and a tank ullage vent valve for pressure control. The temperature stratification effects are investigated, including in the presence of vent valve oscillations. A simulation of temperature stratification effects in a generic cryogenic tank has been implemented in Matlab and results are presented for various tank conditions.

Daigle, Matthew John; Smelyanskiy, Vadim; Boschee, Jacob; Foygel, Michael Gregory

2013-01-01

393

Safety Aspects of Big Cryogenic Systems Design  

NASA Astrophysics Data System (ADS)

Superconductivity and helium cryogenics are key technologies in the construction of large scientific instruments, like accelerators, fusion reactors or free electron lasers. Such cryogenic systems may contain more than hundred tons of helium, mostly in cold and high-density phases. In spite of the high reliability of the systems, accidental loss of the insulation vacuum, pipe rupture or rapid energy dissipation in the cold helium can not be overlooked. To avoid the danger of over-design pressure rise in the cryostats, they need to be equipped with a helium relief system. Such a system is comprised of safety valves, bursting disks and optionally cold or warm quench lines, collectors and storage tanks. Proper design of the helium safety relief system requires a good understanding of worst case scenarios. Such scenarios will be discussed, taking into account different possible failures of the cryogenic system. In any case it is necessary to estimate heat transfer through degraded vacuum superinsulation and mass flow through the valves and safety disks. Even if the design of the helium relief system does not foresee direct helium venting into the environment, an occasional emergency helium spill may happen. Helium propagation in the atmosphere and the origins of oxygen-deficiency hazards will be discussed.

Chorowski, M.; Fydrych, J.; Poli?ski, J.

2010-04-01

394

Realization and performance of cryogenic selection mechanisms  

NASA Astrophysics Data System (ADS)

Within Infra-Red large wavelength bandwidth instruments the use of mechanisms for selection of observation modes, filters, dispersing elements, pinholes or slits is inevitable. The cryogenic operating environment poses several challenges to these cryogenic mechanisms; like differential thermal shrinkage, physical property change of materials, limited use of lubrication, high feature density, limited space etc. MATISSE the mid-infrared interferometric spectrograph and imager for ESO's VLT interferometer (VLTI) at Paranal in Chile coherently combines the light from 4 telescopes. Within the Cold Optics Bench (COB) of MATISSE two concepts of selection mechanisms can be distinguished based on the same design principles: linear selection mechanisms (sliders) and rotating selection mechanisms (wheels).Both sliders and wheels are used at a temperature of 38 Kelvin. The selection mechanisms have to provide high accuracy and repeatability. The sliders/wheels have integrated tracks that run on small, accurately located, spring loaded precision bearings. Special indents are used for selection of the slider/wheel position. For maximum accuracy/repeatability the guiding/selection system is separated from the actuation in this case a cryogenic actuator inside the cryostat. The paper discusses the detailed design of the mechanisms and the final realization for the MATISSE COB. Limited lifetime and performance tests determine accuracy, warm and cold and the reliability/wear during life of the instrument. The test results and further improvements to the mechanisms are discussed.

Aitink-Kroes, Gabby; Bettonvil, Felix; Kragt, Jan; Elswijk, Eddy; Tromp, Niels

2014-07-01

395

Liquid Cryogenic Target Development for Fast Ignition*  

NASA Astrophysics Data System (ADS)

As an alternative to foam-stabilized cryogenic solid D-T fuel layers for indirect-drive fast ignitor targets, which will tend to ?-layer to a nonuniform distribution in a reentrant cone geometry [1], we are investigating hemispherical cryogenic fast ignition capsules with a liquid fuel layer confined between a thick outer ablator shell and a thin inner shell [2]. The shape and surface quality of the fuel layer is determined entirely by the characteristics of the bounding shells. In the present design, structural support for the thin (4.5 um) hemispherical GDP inner shell is provided by a mounting ring. Fabrication of stronger thin Be hemi-shells is also being investigated. Technology issues for liquid cryogenic fuel capsule development and progress toward demonstration of a working target will be presented. [1] J.K. Hoffer et al., Fusion Sci. Technol. 50, 15 (2006). [2] D.L. Hanson et al., Fusion Sci. Technol. 49, 500 (2006). *Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

Hanson, D. L.; Russell, C.; Vesey, R. A.; Schroen, D. G.; Taylor, J. L.; Back, C. A.; Steinman, D.; Nikroo, A.; Kaae, J. L.; Giraldez, E.; Johnston, R. R.; Youngman, K.

2007-11-01

396

Demonstration of Microsphere Insulation in Cryogenic Vessels  

NASA Astrophysics Data System (ADS)

While microspheres have been recognized as a legitimate insulation material for decades, actual use in full-scale cryogenic storage tanks has not been demonstrated until now. The performance and life-cycle-cost advantages previously predicted have now been proven. Most bulk cryogenic storage tanks are insulated with either multilayer insulation (MLI) or perlite. Microsphere insulation, consisting of hollow glass bubbles, combines in a single material the desirable properties that other insulations only have individually. The material has high crush strength, low density, is noncombustible, and performs well in soft vacuum. These properties were proven during recent field testing of two 22,700-L (6,000-gallon) liquid nitrogen tanks, one insulated with microsphere insulation and the other with perlite. Normal evaporation rates (NER) for both tanks were monitored with precision test equipment and insulation levels within the tanks were observed through view ports as an indication of insulation compaction. Specific industrial applications were evaluated based on the test results and beneficial properties of microsphere insulation. Over-the-road trailers previously insulated with perlite will benefit not only from the reduced heat leak, but also the reduced mass of microsphere insulation. Economic assessments for microsphere-insulated cryogenic vessels including life-cycle cost are also presented.

Baumgartner, R. G.; Myers, E. A.; Fesmire, J. E.; Morris, D. L.; Sokalski, E. R.

2006-04-01

397

Modifications developed to improve x-ray detection devices  

NASA Technical Reports Server (NTRS)

Improvements in the development of x-ray detection devices are described. Emphasis is placed on lowering the temperature in order to achieve better x-ray response. A simplified charge integrator schematic is presented along with supporting tables. By using cryogenic operating temperatures, these x-ray detectors may eventually surpass the performance of the best semiconductor detectors.

1994-01-01

398

Neutron spin manipulation devices using YBCO films  

NASA Astrophysics Data System (ADS)

The Meissner effect in a thin-film superconductor can be used to create a sharp boundary between regions of different magnetic field and hence can be used as a component of neutron spin manipulation devices. We have developed two cryogenic neutron spin manipulation devices using single-crystal, high-Tc, YBCO films, which can be cooled without using liquid cryogens and eliminate small angle scattering associated with polycrystalline films. The devices are a spin flipper and a spin precession device both of which use 350-nm-thick YBCO films covered with gold on a 0.5 mm thick sapphire substrate. The spin flipper consists of one such film mounted on an oxygen-free copper frame and connected to a closed-cycle He refrigerator. The flipper is capable of working with a maximum neutron beam size of 42 x 42 mm2 and can be used with both vertical and horizontal guide fields. The spin precession device was constructed by mounting two of the YBCO films parallel to one another with an H-magnet between them. By changing the current through the H - magnet, the precession of the neutron polarisation between the films can be controlled. Tests at the Low Energy Neutron Source (LENS) show that this device is capable of generating controlled spin precession for a neutron beam up to 20 x 20 mm2 in cross section.

Wang, T.; Li, F.; Parnell, S. R.; Hamilton, W. A.; Kaiser, H.; Washington, A. L.; Baxter, D. V.; Pynn, R.

2014-07-01

399

Cryogenic Technology Development For The MEG Liquid Xenon Calorimeter  

SciTech Connect

Cryogenic key technologies have been developed for the muon rare decay experiment (MEG) at the Paul Scherrer Institute, Switzerland. These technologies are the high power pulse tube cryocooler for precise temperature and pressure control of liquid xenon in the calorimeter, a purification system with a cryogenic liquid pump and a cryogenic dewar with 1000 L storage capacity. The paper describes the general concepts and the first test results of each technology. All the results imply a promising performance for the coming MEG experiment.

Haruyama, Tomiyoshi [KEK, High Energy Accelerator Research Organization 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

2008-02-21

400

Rapid-Chill Cryogenic Coaxial Direct-Acting Solenoid Valve  

NASA Technical Reports Server (NTRS)

A commercially available cryogenic direct- acting solenoid valve has been modified to incorporate a rapid-chill feature. The net effect of the modifications is to divert some of the cryogenic liquid to the task of cooling the remainder of the cryogenic liquid that flows to the outlet. Among the modifications are the addition of several holes and a gallery into a valve-seat retainer and the addition of a narrow vent passage from the gallery to the atmosphere.

Richard, James; Castor, Jim; Sheller, Richard

2006-01-01

401

Friction Stir Welded Thin Wall Cryogenic Tank Skins  

Microsoft Academic Search

A cryogenic propellant tank is the common element of trans-planetary transportation systems, in-space storage depots, lunar landers, in-space habitats\\/laboratories, ascent\\/descent, and launch vehicles. Lockheed Martin's (LM) cryogenic tank approach integrates Friction Stir Welding (FSW) with thin-gage aluminum monocoque structural design, common spin formed FSW domes and variable tank lengths to tailor the cryogenic tank from smaller stages, such as landers

David M. Potter; Jennifer A. Takeshita; Michael J. Holguin

2007-01-01

402

Friction Stir Welded Thin Wall Cryogenic Tank Skins  

Microsoft Academic Search

A cryogenic propellant tank is the common element of trans-planetary transportation systems, in-space storage depots, lunar landers, in-space habitats\\/laboratories, ascent\\/descent, and launch vehicles. Lockheed Martin’s (LM) cryogenic tank approach integrates Friction Stir Welding (FSW) with thin-gage aluminum monocoque structural design, common spin formed FSW domes and variable tank lengths to tailor the cryogenic tank from smaller stages, such as landers

David M. Potter; Jennifer A. Takeshita; Michael J. Holguin

2007-01-01

403

The sorption heat pipe—a new device for thermal control and active cooling  

NASA Astrophysics Data System (ADS)

The sorption heat pipe (SHP) is a new heat transfer device, which can be used as a sorption cooler or as a heat pipe. The SHP has a sorbent bed (adsorber/desorber and evaporator) at one end and a condenser+evaporator at the other end. This device is insensitive to some " g" acceleration and could be suggested for space and ground application. The most crucial feature of this device is that in different cases it can be used, for example, as a loop heat pipe, because they have the same evaporator and condenser, or as a SHP. The SHP can be used also as a cryogenic cooler. The SHP is convenient for cryogenic fluid storage, when the system does not work at low pressure and room temperature, and for use in the active cryogenic thermal control systems of spacecraft in orbit (cold plates for infrared observation of the Earth or space), or as an efficient electronic component cooling device.

Vasiliev, L. L.; Vasiliev, L. L.

2004-03-01

404

Assessment of the performance and radiation damage effects under cryogenic temperatures of a P-channel CCD204s  

NASA Astrophysics Data System (ADS)

CCDs continue to be the detector of choice for high resolution and high performance space applications. One perceived drawback is their susceptibility to radiation damage, in particular the formation of trap sites leading to a decrease in charge transfer efficiency. To that end, ESA has started a programme to investigate a new generation of devices based upon p-channel technology. The expectation is that once mature, p-channel devices may offer a significant increase in tolerance to proton radiation over traditional n-type buried channel CCDs. Early studies of e2v devices to assess the radiation hardness of p-channel devices were limited by the quality of devices available, however more recently, good quality p-channel CCD204s have been manufactured and studied. A more detailed evaluation of p-channel CCDs is now underway to realise the full potential of the technology for use in future high radiation environment space missions. A key aspect is the development of a cryogenic test rig that will allow for the first time a direct comparison of the radiation damage effects when the irradiation is performed both traditionally unbiased at room temperature and cryogenically with the device operational. Subsequent characterisations will also be performed on the cryogenic device after periods of storage at room temperature to investigate the potential annealing effects upon the lattice damage. Here we describe and present early results from an extensive programme of testing which will address all key performance parameters for p-channel CCDs, such as full electro-optical characterisation, assessment of radiation hardness and investigation of trap species.

Murray, Neil J.; Holland, Andrew D.; Gow, Jason P. D.; Hall, David J.; Stefanov, Konstantin D.; Dryer, Ben J.; Barber, Simeon; Burt, David J.

2014-07-01

405

Cryogenic Test of a Coaxial Coupling Scheme for Fundamental and Higher Order Modes in Superconducting Cavities  

SciTech Connect

A coaxial coupling device located in the beam pipe of the TESLA type superconducting cavities provides for better propagation of Higher Order Modes (HOMs) and their strong damping in appropriate HOM couplers. Additionally, it also provides efficient coupling for fundamental mode RF power into the superconducting cavity. The whole coupling device can be designed as a detachable system. If appropriately dimensioned, the magnetic field can be minimized to a negligible level at the flange position. This scheme, presented previously*, provides for several advantages: strong HOM damping, flangeable solution, exchangeability of the HOM damping device on a cavity, less complexity of the superconducting cavity, possible cost advantages. This contribution will describe the results of the first cryogenic test.

J.K. Sekutowicz, P. Kneisel

2009-05-01

406

REVIEW OF SUPERCONDUCTING MAGNETOMETERS AND CRYOGENIC REFRIGERATION TECHNIQUES  

E-print Network

3. REVIEW OF SUPERCONDUCTING MAGNETOMETERS AND CRYOGENIC REFRIGERATION TECHNIQUES By W. S. GOREE and handling problems may be encountered in field applications. Closed cycle miniature refrigerators could make

Boyer, Edmond

407

Commissioning the cryogenic system of the first LHC sector  

SciTech Connect

The LHC machine, composed of eight sectors with superconducting magnets and accelerating cavities, requires a complex cryogenic system providing high cooling capacities (18 kW equivalent at 4.5 K and 2.4 W at 1.8 K per sector produced in large cold boxes and distributed via 3.3-km cryogenic transfer lines). After individual reception tests of the cryogenic subsystems (cryogen storages, refrigerators, cryogenic transfer lines and distribution boxes) performed since 2000, the commissioning of the cryogenic system of the first LHC sector has been under way since November 2006. After a brief introduction to the LHC cryogenic system and its specificities, the commissioning is reported detailing the preparation phase (pressure and leak tests, circuit conditioning and flushing), the cool-down sequences including the handling of cryogenic fluids, the magnet powering phase and finally the warm-up. Preliminary conclusions on the commissioning of the first LHC sector will be drawn with the review of the critical points already solved or still pending. The last part of the paper reports on the first operational experience of the LHC cryogenic system in the perspective of the commissioning of the remaining LHC sectors and the beam injection test.

Millet, F.; Claudet, S.; Ferlin, G.; Perin, A.; Riddone, G.; Serio, L.; Soubiran, M.; Tavian, L.; /CERN; Ronayette, L.; /GHMFL, Grenoble; Rabehl, R.; /Fermilab

2007-12-01

408

Cryogenic optical tests of a lightweight HIP beryllium mirror  

NASA Technical Reports Server (NTRS)

Five interferometric tests were conducted at cryogenic temperatures on a lightweight, 50 cm diameter, hot isostatic pressed (HIP) beryllium mirror in the Ames Research Center (ARC) Cryogenic Optics Test Facility. The purpose of the tests was to determine the stability of the mirror's figure when cooled to cryogenic temperatures. Test temperatures ranged from room ambient to 8 K. One cycle to 8 K and five cycles to 80 K were performed. Optical and thermal test methods are described. Data is presented to show the amount of cryogenic distortion and hysteresis present in the mirror when measured with an earlier, Shack interferometer, and with a newly-acquired, phase-measuring interferometer.

Melugin, Ramsey K.; Miller, Jacob H.; Young, J. A.; Howard, Steven D.; Pryor, G. Mark

1989-01-01

409

Commissioning the Cryogenic System of the First Lhc Sector  

NASA Astrophysics Data System (ADS)

The LHC machine, composed of eight sectors with superconducting magnets and accelerating cavities requires a complex cryogenic system providing high cooling capacities (18 kW equivalent at 4.5 K and 2.4 kW at 1.8 K per sector produced in large cold boxes and distributed via 3.3-km cryogenic transfer lines). After individual reception tests of the cryogenic subsystems (cryogen storages, refrigerators, cryogenic transfer lines and distribution boxes) performed since 2000, the commissioning of the cryogenic system of the first LHC sector has been under way since November 2006. After a brief introduction to the LHC cryogenic system and its specificities, the commissioning is reported detailing the preparation phase (pressure and leak tests, circuit conditioning and flushing), the cool-down sequences including the handling of cryogenic fluids, the magnet powering phase and finally the warm-up. Preliminary conclusions on the commissioning of the first LHC sector will be drawn with the review of the critical points already solved or still pending. The last part of the paper reports on the first operational experience of the LHC cryogenic system in the perspective of the commissioning of the remaining LHC sectors and the beam injection test.

Millet, F.; Claudet, S.; Ferlin, G.; Perin, A.; Rabehl, R.; Riddone, G.; Ronayette, L.; Serio, L.; Soubiran, M.; Tavian, L.

2008-03-01

410

Cryopumping in Cryogenic Insulations for a Reusable Launch Vehicle  

NASA Technical Reports Server (NTRS)

Testing at cryogenic temperatures was performed to verify the material characteristics and manufacturing processes of reusable propellant tank cryogenic insulations for a Reusable Launch Vehicle (RLV). The unique test apparatus and test methods developed for the investigation of cryopumping in cryogenic insulations are described. Panel level test specimens with various types of cryogenic insulations were subjected to a specific thermal profile where the temperature varied from -262 C to 21 C. Cryopumping occurred if the interior temperature of the specimen exhibited abnormal temperature fluctuations, such as a sudden decrease in temperature during the heating phase.

Johnson, Theodore F.; Weiser, Erik S.; Grimsley, Brian W.; Jensen, Brian J.

2003-01-01

411

Magnetic characterization for cryogenic permanent-magnet undulators: a first result.  

PubMed

The cryogenic permanent-magnet undulator (CPMU) is a novel insertion device recently proposed at SPring-8, in which permanent magnets (PMs) are cooled to cryogenic temperatures to improve the magnetic performances, such as remanence and coercivity. A new measurement system for carrying out high-precision magnetic field mapping using a Hall probe has been developed in order to characterize the magnetic field generated by PM arrays at cryogenic temperatures. In this system, alignment of the Hall probe was dynamically performed by means of detecting the variation in its transverse position using optical laser beams introduced into the vacuum chamber. Magnetic measurements of a CPMU prototype were made at different temperatures in order to investigate variations of the magnetic performances owing to temperature. The maximum remanence deduced from the average peak value of the field profile was found to be close to that obtained from a former measurement with a single piece of the same PM material. In addition, the error components in the field profile were found to be insensitive to temperature in terms of the electron trajectory and phase error. This result suggests that the field correction of CPMUs can be performed based on the field profile measured at room temperature, which considerably reduces the task and time necessary for construction of CPMUs. PMID:17717383

Tanaka, Takashi; Tsuru, Rieko; Nakajima, Takashige; Kitamura, Hideo

2007-09-01

412

Cryogenic high-heat-load optics at the advanced photon source  

SciTech Connect

Cryogenically cooled silicon monochromators have found wide application at the Advanced Photon Source (APS) and other third-generation synchrotron radiation facilities. Currently, 17 insertion device beamlines at the APS are implementing cryogenic, silicon double-crystal monochromators (DCM) at the first optical element. Recently, several silicon crystal monochromators internally cooled with liquid nitrogen have been tested on the sector 1-ID undulator beamline at the APS. Rocking curves at various energies were measured simultaneously in first and third order from a Si(111) DCM in the Bragg reflection geometry at a fixed undulator gap of 11.1 mm. The crystal exhibited a sub-arc second thermal broadening of the rocking curve over a first order energy range from 6.0 to 17.0 keV up to a maximum incident power of 561 W in a 2.5 V x 2.0 H mm{sup 2} beam. It has been demonstrated that cryogenic silicon monochromators can handle the highest power beams from hard x-ray undulators at the APS without significant thermo-mechanical distortion.

Rogers, C.S.

1997-06-01

413

Cryogenic high-heat-load optics at the advanced photon source (Invited)  

SciTech Connect

Cryogenically cooled silicon monochromators have found wide application at the Advanced Photon Source (APS) and other third-generation synchrotron radiation facilities. Currently, 17 insertion device beamlines at the APS are implementing cryogenic, silicon double-crystal monochromators (DCM) as the first optical element. Recently, several silicon crystal monochromators internally cooled with liquid nitrogen have been tested on the sector 1-ID undulator beamline at the APS. Rocking curves at various energies were measured simultaneously in first and third order from a Si(111) DCM in the Bragg reflection geometry at a fixed undulator gap of 11.1 mm. The crystal exhibited sub-arc second thermal broadening of the rocking curve over a first order energy range from 6.0 to 17.0 keV up to a maximum incident power of 561 W in a 2.5 Vx2.0 H mm{sup 2} beam. It has been demonstrated that cryogenic silicon monochromators can handle the highest power beams from hard x-ray undulators at the APS without significant thermo-mechanical distortion.

Rogers, C. S. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

1997-07-01

414

Cryogenic high-heat-load optics at the advanced photon source (Invited)  

SciTech Connect

Cryogenically cooled silicon monochromators have found wide application at the Advanced Photon Source (APS) and other third-generation synchrotron radiation facilities. Currently, 17 insertion device beamlines at the APS are implementing cryogenic, silicon double-crystal monochromators (DCM) as the first optical element. Recently, several silicon crystal monochromators internally cooled with liquid nitrogen have been tested on the sector 1-ID undulator beamline at the APS. Rocking curves at various energies were measured simultaneously in first and third order from a Si(111) DCM in the Bragg reflection geometry at a fixed undulator gap of 11.1 mm. The crystal exhibited sub-arc second thermal broadening of the rocking curve over a first order energy range from 6.0 to 17.0 keV up to a maximum incident power of 561 W in a 2.5V{times}2.0Hmm{sup 2} beam. It has been demonstrated that cryogenic silicon monochromators can handle the highest power beams from hard x-ray undulators at the APS without significant thermo-mechanical distortion. {copyright} {ital 1997 American Institute of Physics.}

Rogers, C.S. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois60439 (United States)

1997-07-01

415

Recommendations for a cryogenic system for ITER (International Thermonuclear Experimental Reactor)  

SciTech Connect

The International Thermonuclear Experimental Reactor (ITER) is a new tokamak design project with joint participation from Japan, the European Community, the Soviet Union, and the United States. ITER will be a large machine requiring up to 100 kW of refrigeration at 4.5 K to cool its superconducting magnets. Unlike earlier fusion experiments, the ITER cryogenic system must handle pulse loads constituting a large percentage of the total load. These come from neutron heating during a fusion burn and from ac losses during ramping of current in the PF (poloidal field) coils. This paper presents a conceptual design for a cryogenic system that meets ITER requirements. It describes a system with the following features: Only time-proven components are used. The system obtains a high efficiency without use of cold pumps or other developmental components. High reliability is achieved by paralleling compressors and expanders and by using adequate isolation valving. The problem of load fluctuations is solved by a simple load-leveling device. The cryogenic system can be housed in a separate building located at a considerable distance from the ITER core, if desired. The paper also summarizes physical plant size, cost estimates, and means of handling vented helium during magnet quench. 4 refs., 4 figs., 3 tabs.

Slack, D.S.

1989-09-20

416

KOTOBUKI-1 apparatus for cryogenic coherent X-ray diffraction imaging  

SciTech Connect

We have developed an experimental apparatus named KOTOBUKI-1 for use in coherent X-ray diffraction imaging experiments of frozen-hydrated non-crystalline particles at cryogenic temperature. For cryogenic specimen stage with small positional fluctuation for a long exposure time of more than several minutes, we here use a cryogenic pot cooled by the evaporation cooling effect for liquid nitrogen. In addition, a loading device is developed to bring specimens stored in liquid nitrogen to the specimen stage in vacuum. The apparatus allows diffraction data collection for frozen-hydrated specimens at 66 K with a positional fluctuation of less than 0.4 ?m and provides an experimental environment to easily exchange specimens from liquid nitrogen storage to the specimen stage. The apparatus was developed and utilized in diffraction data collection of non-crystalline particles with dimensions of ?m from material and biological sciences, such as metal colloid particles and chloroplast, at BL29XU of SPring-8. Recently, it has been applied for single-shot diffraction data collection of non-crystalline particles with dimensions of sub-?m using X-ray free electron laser at BL3 of SACLA.

Nakasako, Masayoshi; Takayama, Yuki; Oroguchi, Tomotaka; Sekiguchi, Yuki; Kobayashi, Amane [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan) [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Shirahama, Keiya [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)] [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan); Yamamoto, Masaki; Hikima, Takaaki; Yonekura, Koji; Maki-Yonekura, Saori; Kohmura, Yoshiki; Inubushi, Yuichi [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)] [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Takahashi, Yukio; Suzuki, Akihiro [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan) [RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan); Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Matsunaga, Sachihiro; Inui, Yayoi [Department of Applied Biological Science Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan)] [Department of Applied Biological Science Faculty of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510 (Japan); Tono, Kensuke; Kameshima, Takashi; Joti, Yasumasa [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan)] [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Hoshi, Takahiko [Kohzu Precision Co., Ltd., 2-6-15 Kurigi, Aso-ku, Kawasaki, Kanagawa 215-8521 (Japan)] [Kohzu Precision Co., Ltd., 2-6-15 Kurigi, Aso-ku, Kawasaki, Kanagawa 215-8521 (Japan)

2013-09-15

417

Cryogenic probe station for use in automated microwave and noise figure measurements  

NASA Technical Reports Server (NTRS)

A cryogenic measurement system capable of performing on-wafer RF testing of semiconductor devices and circuits has been developed. This 'CryoProbe Station' can wafer-probe devices and circuits at cryogenic temperatures, thus eliminating the need for wire bonds. The system operates under vacuum created by a sorption pump. It uses an open cycle cooling system that can be cooled with either liquid nitrogen or liquid helium. Presently, it can reach temperatures, as low as 80 K and 37 K for each of the coolants, respectively. The temperature can be raised using a heater and it is stabilized to within 0.2 K by use of a temperature controller. The CryoProbe Station features a 1 by 2 inch stage that can hold large circuits and calibration standards simultaneously. The system is used with a Hewlett Packard 8510C Automatic Network Analyzer (ANA) to obtain S-parameter data over the frequency range 0.045-26.5 GHz. S-parameter data on HEMT (high electron mobility transistors) devices has been obtained with this station. With the use of DEEMBED software from NIST, detailed transmission line studies have been performed. Although the CryoProbe Station is designed for frequencies up to 26.5 GHz, useful transmission line data has been obtained for frequencies as high as 40 GHz. The CryoProbe station has also been used with the ATN noise figure measurement system to perform automatic, temperature dependent noise figure measurements.

Taub, Susan R.; Alterovitz, Samuel A.; Young, Paul G.; Ebihara, Ben T.; Romanofsky, Robert R.

1994-01-01

418

Cryogenic probe station for use in automated microwave and noise figure measurements  

NASA Astrophysics Data System (ADS)

A cryogenic measurement system capable of performing on-wafer RF testing of semiconductor devices and circuits has been developed. This 'CryoProbe Station' can wafer-probe devices and circuits at cryogenic temperatures, thus eliminating the need for wire bonds. The system operates under vacuum created by a sorption pump. It uses an open cycle cooling system that can be cooled with either liquid nitrogen or liquid helium. Presently, it can reach temperatures, as low as 80 K and 37 K for each of the coolants, respectively. The temperature can be raised using a heater and it is stabilized to within 0.2 K by use of a temperature controller. The CryoProbe Station features a 1 by 2 inch stage that can hold large circuits and calibration standards simultaneously. The system is used with a Hewlett Packard 8510C Automatic Network Analyzer (ANA) to obtain S-parameter data over the frequency range 0.045-26.5 GHz. S-parameter data on HEMT (high electron mobility transistors) devices has been obtained with this station. With the use of DEEMBED software from NIST, detailed transmission line studies have been performed. Although the CryoProbe Station is designed for frequencies up to 26.5 GHz, useful transmission line data has been obtained for frequencies as high as 40 GHz. The CryoProbe station has also been used with the ATN noise figure measurement system to perform automatic, temperature dependent noise figure measurements.

Taub, Susan R.; Alterovitz, Samuel A.; Young, Paul G.; Ebihara, Ben T.; Romanofsky, Robert R.

1994-03-01

419

Superfluid helium quantum interference devices (SHeQUIDs): principles and performance  

NASA Astrophysics Data System (ADS)

We describe recent progress in developing a superfluid helium analog of the superconducting dc-SQUID. The devices tested thus far are sensitive detectors of rotation as well as useful probes for studies of superfluidity. The key ingredients of the superfluid helium quantum interference device (SHeQUID) involve commercially available technology and modest cryogenic facilities.

Packard, R. E.; Sato, Y.

2014-12-01

420

Cavity optomechanics with Si3N4 membranes at cryogenic temperatures  

E-print Network

We describe a cryogenic cavity-optomechanical system that combines Si3N4 membranes with a mechanically-rigid Fabry-Perot cavity. The extremely high quality-factor frequency products of the membranes allow us to cool a MHz mechanical mode to a phonon occupation of less than 10, starting at a bath temperature of 5 kelvin. We show that even at cold temperatures thermally-occupied mechanical modes of the cavity elements can be a limitation, and we discuss methods to reduce these effects sufficiently to achieve ground state cooling. This promising new platform should have versatile uses for hybrid devices and searches for radiation pressure shot noise.

Purdy, T P; Yu, P -L; Regal, C A

2012-01-01

421

Cavity optomechanics with Si3N4 membranes at cryogenic temperatures  

E-print Network

We describe a cryogenic cavity-optomechanical system that combines Si3N4 membranes with a mechanically-rigid Fabry-Perot cavity. The extremely high quality-factor frequency products of the membranes allow us to cool a MHz mechanical mode to a phonon occupation of less than 10, starting at a bath temperature of 5 kelvin. We show that even at cold temperatures thermally-occupied mechanical modes of the cavity elements can be a limitation, and we discuss methods to reduce these effects sufficiently to achieve ground state cooling. This promising new platform should have versatile uses for hybrid devices and searches for radiation pressure shot noise.

T. P. Purdy; R. W. Peterson; P. -L. Yu; C. A. Regal

2012-08-31

422

Apparatus for measuring tensile and compressive properties of solid materials at cryogenic temperatures  

DOEpatents

An apparatus for evaluating the tensile and compressive properties of material samples at very low or cryogenic temperatures employs a stationary frame and a dewar mounted below the frame. A pair of coaxial cylindrical tubes extend downward towards the bottom of the dewar. A compressive or tensile load is generated hydraulically and is transmitted by the inner tube to the material sample. The material sample is located near the bottom of the dewar in a liquid refrigerant bath. The apparatus employs a displacement measuring device, such as a linear variable differential transformer, to measure the deformation of the material sample relative to the amount of compressive or tensile force applied to the sample.

Gonczy, John D. (Oaklawn, IL); Markley, Finley W. (St. Charles, IL); McCaw, William R. (Burr Ridge, IL); Niemann, Ralph C. (Downers Grove, IL)

1992-01-01

423

New cryogenic environment for beamline ID22 at the European Synchrotron Radiation Facility  

NASA Astrophysics Data System (ADS)

A compact minicryostat has been well adapted on the hard x-ray microprobe ID22 of the European Synchrotron Radiation Facility. For variable low-temperature investigations, its special technical design provides precise scanning microscopy and allows easy access for multiple detection modes. Based on x-ray excited optical luminescence technique on the micrometer scale, details of the equipment, its temperature calibration, and typical results are described. Data collections from InAs quantum heterostructures support the excellent thermal performance of the novel cryogenic device.

Martínez-Criado, G.; Steinmann, R.; Alén, B.; Labrador, A.; Fuster, D.; Ripalda, J. M.; Homs, A.; Labouré, S.; Susini, J.

2007-02-01

424

New cryogenic environment for beamline ID22 at the European Synchrotron Radiation Facility.  

PubMed

A compact minicryostat has been well adapted on the hard x-ray microprobe ID22 of the European Synchrotron Radiation Facility. For variable low-temperature investigations, its special technical design provides precise scanning microscopy and allows easy access for multiple detection modes. Based on x-ray excited optical luminescence technique on the micrometer scale, details of the equipment, its temperature calibration, and typical results are described. Data collections from InAs quantum heterostructures support the excellent thermal performance of the novel cryogenic device. PMID:17578147

Martínez-Criado, G; Steinmann, R; Alén, B; Labrador, A; Fuster, D; Ripalda, J M; Homs, A; Labouré, S; Susini, J

2007-02-01

425

Nd 2Fe 14B and Pr 2Fe 14B magnets characterisation and modelling for cryogenic permanent magnet undulator applications  

NASA Astrophysics Data System (ADS)

Cryogenic permanent magnet undulators take benefit from improved magnetic properties of RE 2Fe 14B (Rare Earth based magnets) at cryogenic temperatures for achieving short period high magnetic field. In particular, using Praseodymium instead of Neodymium generally employed for insertion devices avoids limitation due to Spin Reorientation Transition phenomenon. Magnetic properties of magnet samples (Nd 2Fe 14B and Pr 2Fe 14B) versus temperature have been investigated and applied to a 20 mm period Nd 2Fe 14B (BH50) and to a 18 mm period Pr 2Fe 14B (CR53) systems. Four period undulators have been built, characterised and compared to the models.

Benabderrahmane, C.; Berteaud, P.; Valléau, M.; Kitegi, C.; Tavakoli, K.; Béchu, N.; Mary, A.; Filhol, J. M.; Couprie, M. E.

2012-03-01

426

Large Cryogenic Infrastructure for LHC Superconducting Magnet and Cryogenic Component Tests: Layout, Commissioning and Operational Experience  

SciTech Connect

The largest cryogenic test facility at CERN, located at Zone 18, is used to validate and to test all main components working at cryogenic temperature in the LHC (Large Hadron Collider) before final installation in the machine tunnel. In total about 1300 main dipoles, 400 main quadrupoles, 5 RF-modules, eight 1.8 K refrigeration units will be tested in the coming years.The test facility has been improved and upgraded over the last few years and the first 18 kW refrigerator for the LHC machine has been added to boost the cryogenic capacity for the area via a 25,000 liter liquid helium dewar. The existing 6 kW refrigerator, used for the LHC Test String experiments, will also be employed to commission LHC cryogenic components.We report on the design and layout of the test facility as well as the commissioning and the first 10,000 hours operational experience of the test facility and the 18 kW LHC refrigerator.

Calzas, C.; Chanat, D.; Knoops, S.; Sanmarti, M.; Serio, L. [Accelerator Technology Division, CERN, 1211 Geneva 23 (Switzerland)

2004-06-23

427

Use of Capillaries for Macromolecular Crystallization in a Cryogenic Dewar  

NASA Technical Reports Server (NTRS)

The Enhanced Gaseous Nitrogen (EGN) Dewar is a cryogenic dry shipper with a sealed cylinder inserted inside along with a temperature-monitoring device, and is intended for macromolecular crystallization experiments on the International Space Station. Within the Dewar, each crystallization experiment is contained as a solution within a plastic capillary. The standard procedure for loading samples in these tubes has involved rapid freezing of the precipitant and biomolecule solution directly in liquid nitrogen; this method, however, often results in uncontrolled formation of air voids. These air pockets, or bubbles, then can lead to irreproducible crystallization results. A novel protocol has been developed to prevent formation of bubbles, and this has been tested in the laboratory as well as aboard the International Space Station during a 42-day long mission of July/August of 2001. Furthermore, gain or loss of mass from solutions within the capillaries revealed that mass transport amongst separated tubes occurred, and that this mass transport was determined by the hygroscopic character of a solution contained in any given tube. The sample volume and the surface area of the plastic capillary tube also related to the observed mass transport.

Ciszak, Ewa; Hammons, Aaron S.; Hong, Young Soo; Curreri, Peter A. (Technical Monitor)

2001-01-01

428

Use of Capillaries for Macromolecular Crystallization in a Cryogenic Dewar  

NASA Technical Reports Server (NTRS)

The enhanced gaseous nitrogen (EGN) dewar is a cryogenic dry shipper with a sealed cylinder inserted inside along with a temperature monitoring device, and is intended for macromolecular crystallization experiments on the International Space Station. Within the dewar, each crystallization experiment is contained as a solution within a plastic capillary tube. The standard procedure for loading samples in these tubes has involved rapid freezing of the precipitant and biomolecular solution, e.g., protein, directly in liquid nitrogen; this method, however, often resulted in uncontrolled formation of air voids, These air pockets, or bubbles, can lead to irreproducible crystallization results. A novel protocol has been developed to prevent formation of bubbles, and this has been tested in the laboratory as well as aboard the International Space Station during a 42-day long mission of July/August 2001. The gain or loss of mass from solutions within the plastic capillaries revealed that mass transport occurred among separated tubes, and that this mass transport was dependent upon the hygroscopic character of the solution contained in any given tube. The surface area of the plastic capillary tube also related to the observed mass transport. Furthermore, the decreased mass of solutions of-protein correlated to observed formation of protein crystals.

Ciszak, Ewa; Hammons, Aaron S.; Hong, Young Soo

2002-01-01

429

The development of a cryogenic over-pressure pump  

SciTech Connect

A cryogenic over-pressure pump (OPP) was tested in the prototype telescope liquid nitrogen (LN2) cooling system for the Dark Energy Survey (DES) Project. This OPP consists of a process cylinder (PC), gas generator, and solenoid operated valves (SOVs). It is a positive displacement pump that provided intermittent liquid nitrogen (LN2) flow to an array of charge couple devices (CCDs) for the prototype Dark Energy Camera (DECam). In theory, a heater submerged in liquid would generate the drive gas in a closed loop cooling system. The drive gas would be injected into the PC to displace that liquid volume. However, due to limitations of the prototype closed loop nitrogen system (CCD cooling system) for DECam, a quasiclosed-loop nitrogen system was created. During the test of the OPP, the CCD array was cooled to its designed set point temperature of 173K. It was maintained at that temperature via electrical heaters. The performance of the OPP was captured in pressure, temperature, and flow rate in the CCD LN2 cooling system at Fermi National Accelerator Laboratory (FNAL)

Alvarez, M.; Cease, H.; Flaugher, B.; Flores, R.; Lathrop, A. [Fermi National Accelerator Laboratory, Batavia, IL, 60510 (United States); Garcia, J. [Illinois Institute of Technology, Chicago, IL, 60616 A (United States); Ruiz, F. [Illinois Institute of Technology, Chicago, IL, 60616 (United States)

2014-01-29

430

Two cryogenic mechanisms for Earth based infrared astronomy  

Microsoft Academic Search

The Infrared Multi-Object Spectrograph (IRMOS) is a ground based, low budget, principle investigator class, cryogenic instrument for IR astronomy. The instrument envelope and optomechanical designs were defined prior to beginning mechanism detailed designs, so serious volumetric constraints were encountered during the advanced design phase. This fact and the high precision requirements, room temperature and cryogenic operation, and budgetary constraints led

J. P. Schepis; M. W. McClendon; M. M. Webb; S. W. Zewari; J. E. Hylan; M. P. Barthelmy; J. MacKenty

2003-01-01

431

Unlined Reuseable Filament Wound Composite Cryogenic Tank Testing  

NASA Technical Reports Server (NTRS)

An unlined reusable filament wound composite cryogenic tank was tested at the Marshall Space Flight Center using LH2 cryogen and pressurization to 320 psig. The tank was fabricated by Phillips Laboratory and Wilson Composite Group, Inc., using an EnTec five-axis filament winder and sand mandrels. The material used was IM7/977-2 (graphite/epoxy).

Murphy, A. W.; Lake, R. E.; Wilkerson, C.

1999-01-01

432

Zero Gravity Cryogenic Vent System Concepts for Upper Stages  

Microsoft Academic Search

The capability to vent in zero gravity without resettling is a technology need that involves practically all uses of sub-critical cryogenics in space. Venting without resettling would extend cryogenic orbital transfer vehicle capabilities. However, the lack of definition regarding liquid\\/ullage orientation coupled with the somewhat random nature of the thermal stratification and resulting pressure rise rates, lead to significant technical

Alain Ravex; Robin Flachbart; Barney Holt

1999-01-01

433

Design of a cryogenic IR detector with integrated optics  

Microsoft Academic Search

Cryogenically cooled IR detectors, which are used in applications such as situational awareness, search & track, missile launch and approach warning, typically use wide angle, single field of view optical systems. We describe a complete IR imaging optical assembly for such applications, which is mounted inside a cold shield and is maintained at a stabilized cryogenic temperature inside the dewar.

Michael Singer; Dov Oster

2010-01-01

434

TESLA Report 2001-36 THE TESLA CRYOGENIC ACCELERATOR MODULES  

E-print Network

of the cryostat. The cryostat outer vacuum vessel is constructed from carbon steel and has a standard diameter by having a single long continuous string of about 2.5 km, called cryogenic unit [1]. Each long module). The modules are directly connected each other into a cryogenic unit. 2 CRYOSTAT Figure 1 shows a cross section

435

Optimal design of cryogenic air separation columns under uncertainty  

Microsoft Academic Search

Cryogenic air separation, while widely used in industry, is an energy intensive process. Effective design can improve efficiency and reduce energy consumption, however, uncertainties can make determination of the optimal design difficult. This paper addresses the conceptual design of cryogenic air separation process under uncertainty. A rigorous, highly nonlinear model of three integrated columns is developed to capture the coupled

Yu Zhu; Sean Legg; Carl D. Laird

2010-01-01

436

Analysis Of Transfer Of Cryogens In Low Gravity  

NASA Technical Reports Server (NTRS)

Report discusses calculations of thermodynamic aspects of refilling tanks with cryogenic liquids in low or zero gravity. Calculations required to design prototype system resupplying cryogenic propellant liquids to re-usable spacecraft not returning to Earth. Equations and computer programs developed for thermodynamic analysis used to extrapolate important design information from orbiting small-scale versions of system.

Defelice, David M.; Aydelott, John C.

1993-01-01

437

Contracting/expanding self-sealing cryogenic tube seals  

NASA Technical Reports Server (NTRS)

Contracting/expanding self-sealing cryogenic tube seals are disclosed which use the different properties of thermal contraction and expansion of selected dissimilar materials in accord with certain design criteria to yield self-tightening seals via sloped-surface sealing. The seals of the subject invention are reusable, simple to assemble, and adaptable to a wide variety of cryogenic applications.

Jia, Lin X. (Inventor)

1997-01-01

438

Contracting/expanding self-sealing cryogenic tube seals  

NASA Technical Reports Server (NTRS)

Contracting/expanding self-sealing cryogenic tube seals are disclosed which use the different properties of thermal contraction and expansion of selected dissimilar materials in accord with certain design criteria to yield self-tightening seals via sloped-surface sealing. The seals of the subject invention are reusable, simple to assemble, adaptable to a wide variety of cryogenic applications.

Jia, Lin X. (Inventor)

1997-01-01

439

Novel design of an all-cryogenic RF pound circuit  

NASA Technical Reports Server (NTRS)

We report on the design, construction and test of a new all-cryogenic RF Pound circuit used to stabilize a 100 MHz VCXO. Here, all active and passive RF components used to accomplish the phase modulation and detect a PM to AM conversion have been installed into the cryogenic environment.

Basu, Ronni; Wang, Rabi T.; Dick, G. John

2005-01-01

440

Measurement techniques for cryogenic Ka-band microstrip antennas  

NASA Technical Reports Server (NTRS)

The measurement of cryogenic antennas poses unique logistical problems since the antenna under test must be embedded in a cooling chamber. A method of measuring the performance of cryogenic microstrip antennas using a closed cycle gas cooled refrigerator in a far field range is described. Antenna patterns showing the performance of gold and superconducting Ka-band microstrip antennas at various temperatures are presented.

Richard, M. A.; Bhasin, K. B.; Gilbert, C.; Metzler, S.; Claspy, P. C.

1991-01-01

441

Materials for cold neutron sources: Cryogenic and irradiation effects  

Microsoft Academic Search

Materials for the construction of cold neutron sources must satisfy a range of demands. The cryogenic temperature and irradiation create a severe environment. Candidate materials are identified and existing cold sources are briefly surveyed to determine which materials may be used. Aluminum- and magnesium-based alloys are the preferred materials. Existing data for the effects of cryogenic temperature and near-ambient irradiation

1990-01-01

442

Long-term stability of a cryogenic diode thermometer  

Microsoft Academic Search

One of the most important qualities for a cryogenic thermometer is its ability to maintain its calibration upon thermal cycling. While it is most preferable to perform slow thermal cycling on cryogenic temperature sensors, it is not always practical to do so. Fast thermal cycling, or thermal shocking, induces stresses within the sensor that at best can cause shifts in

S. S. Courts; P. R. Swinehart

2002-01-01

443

A review of cryogenic thermometry and common temperature sensors  

Microsoft Academic Search

This paper reviews cryogenic temperature sensors and gives an overview of cryogenic thermometry over the range 20 mK to 100 K. It begins with a brief overview of primary thermometry and methods used to realize and disseminate the International Temperature Scale of 1990, ITS-90. A short review of secondary thermometry is presented, focusing the discussion on commonly available sensors. The

C. J. Yeager; S. S. Courts

2001-01-01

444

Forced-convective vitrification with liquid cryogens.  

PubMed

Cell cryopreservation by vitrification generally requires using vitrification solutions with high concentrations of cryoprotectants (CPAs), which are toxic and induce osmotic stresses associated with the addition and removal of CPAs. To increase the cooling rate and reduce the CPA concentration required for vitrification, this study proposed an innovative approach, named forced-convective vitrification with liquid cryogens, in which liquid oxygen at a temperature below its boiling point (LOX(bbp)) was used as the cryogen to reduce the generation of insulating bubbles of gaseous oxygen and the sample was subjected to a constant velocity to remove insulation bubbles from the sample. Results show that changing the cryogen from liquid nitrogen at its boiling temperature (LN(abp)) to LOX(bbp), increasing the sample velocity and reducing the test solution volume increased the cooling rate and thereby decreased the CPA concentration required for vitrification. Using the same velocity (1.2 m/s), the cooling rate achieved with LOX(bbp) was 2.3-fold greater than that achieved with LN(abp). With LOX(bbp), the increase in the sample velocity from 0.2 to 1.2 m/s enhanced the cooling rate by 1.9 times. With LOX(bbp), a velocity of 1.2m/s and a test solution volume of 1.73 ?l, the CPA concentration required for vitrification decreased to 25%. These results indicate that the new approach described here can reduce the CPA concentration required for vitrification, and thus decreases the toxicity and osmotic stresses associated with adding and removing the CPA. PMID:23545291

Lyu, Shaw-Ruey; Huang, Jen-Hung; Shih, Wei-Hung; Chen, Yung-Jiun; Hsieh, Wen-Hsin

2013-06-01

445

Cryogenic Scan Mechanism for Fourier Transform Spectrometer  

NASA Technical Reports Server (NTRS)

A compact and lightweight mechanism has been developed to accurately move a Fourier transform spectrometer (FTS) scan mirror (a cube corner) in a near-linear fashion with near constant speed at cryogenic temperatures. This innovation includes a slide mechanism to restrict motion to one dimension, an actuator to drive the motion, and a linear velocity transducer (LVT) to measure the speed. The cube corner mirror is double-passed in one arm of the FTS; double-passing is required to compensate for optical beam shear resulting from tilting of the moving cube corner. The slide, actuator, and LVT are off-the-shelf components that are capable of cryogenic vacuum operation. The actuator drives the slide for the required travel of 2.5 cm. The LVT measures translation speed. A proportional feedback loop compares the LVT voltage with the set voltage (speed) to derive an error signal to drive the actuator and achieve near constant speed. When the end of the scan is reached, a personal computer reverses the set voltage. The actuator and LVT have no moving parts in contact, and have magnetic properties consistent with cryogenic operation. The unlubricated slide restricts motion to linear travel, using crossed roller bearings consistent with 100-million- stroke operation. The mechanism tilts several arc seconds during transport of the FTS mirror, which would compromise optical fringe efficiency when using a flat mirror. Consequently, a cube corner mirror is used, which converts a tilt into a shear. The sheared beam strikes (at normal incidence) a flat mirror at the end of the FTS arm with the moving mechanism, thereby returning upon itself and compensating for the shear

Brasunas, John C.; Francis, John L.

2011-01-01

446

SPICA sub-Kelvin cryogenic chains  

NASA Astrophysics Data System (ADS)

SPICA, a Japanese led mission, is part of the JAXA future science program and is planned for launch in 2018. SPICA will perform imaging and spectroscopic observations in the mid- and far-IR waveband, and is developing instrumentation spanning the 5-400 ?m range. The SPICA payload features several candidate instruments, some of them requiring temperature down to 50 mK. This is currently the case for SAFARI, a core instrument developed by a European-based consortium, and BLISS proposed by CALTECH/JPL in the US. SPICA's distinctive feature is to actively cool its telescope to below 6 K. In addition, SPICA is a liquid cryogen free satellite and all the cooling will be provided by radiative cooling (L2 orbit) down to 30 K and by mechanical coolers for lower temperatures. The satellite will launch warm and slowly equilibrate to its operating temperatures once in orbit. This warm launch approach makes it possible to eliminate a large liquid cryogen tank and to use the mass saved to launch a large diameter telescope (3.2 m). This 4 K cooled telescope significantly reduces its own thermal radiation, offering superior sensitivity in the infrared region. The cryogenic system that enables this warm launch/cooled telescope concept is a key issue of the mission. This cryogenic chain features a number of cooling stages comprising passive radiators, Stirling coolers and several Joule Thomson loops, offering cooling powers at typically 20, 4.5, 2.5 and 1.7 K. The SAFARI and BLISS detectors require cooling to temperatures as low as 50 mK. The instrument coolers will be operated from these heat sinks. They are composed of a small demagnetization refrigerator (ADR) pre cooled by either a single or a double sorption cooler, respectively for SAFARI and BLISS. The BLISS cooler maintains continuous cooling at 300 mK and thus suppresses the thermal equilibrium time constant of the large focal plane. These hybrid architectures allow designing low weight coolers able to reach 50 mK. Because the sorption cooler has extremely low mass for a sub-Kelvin cooler, it allows the stringent mass budget to be met. These concepts are discussed in this paper.

Duband, L.; Duval, J. M.; Luchier, N.; Prouve, T.

2012-04-01

447

Canceling Torque Caused By Boiloff Of Cryogen  

NASA Technical Reports Server (NTRS)

Proposed technique for cancellation of small torques caused by venting of cryogens from tanks in spacecraft adaptable to use in making small corrections in orientations of terrestrial scientific instruments. Torque eliminated by directing exhaust gas through "T" vent. To cancel remaining small torque, that side of "T" from which exhaust produces smaller thrust heated just enough to equalize opposing thrusts. Concept useful in situations in which conventional electromagnetic actuators not suitable because of constraints related to temperature, radiation, or vibration and equipment required to be robust, simple, reliable, light in weight, and without moving parts.

Bhandari, Pradeep

1993-01-01

448

Piezoresistive silicon pressure sensors in cryogenic environment  

NASA Technical Reports Server (NTRS)

This paper presents data on low-temperature measurements of silicon pressure sensors. It was found that both the piezoresistance coefficients and the charge-carrier mobility increase with decreasing temperature. For lightly doped semiconductor materials, the density of free charge carriers decreases with temperature and can freeze out eventually. However, the effect of carrier freeze-out can be minimized by increasing the impurity content to higher levels, at which the temperature dependency of piezoresistance coefficients is reduced. An impurity density of 1 x 10 to the 19th/cu cm was found to be optimal for cryogenic applications of pressure sensor dies.

Kahng, Seun K.; Chapman, John J.

1989-01-01

449

Pressure transducer and system for cryogenic environments  

NASA Technical Reports Server (NTRS)

A silicon pressure die is bonded to a borosilicate substrate above the pneumatic port. A Wheatstone bridge circuit is formed on the silicon pressure die and has bridge elements of silicon doped with boron to a deposit density level of approximately 1 x 10(exp 19)-10(exp 21) boron/cc. A current source is provided to excite the Wheatstone bridge circuit. In addition, a temperature sensor is provided to provide temperature readings. An array may be formed of the resulting pressure transducers. This unique solution of materials permits operation of a pressure transducer in cryogenic environments.

Chapman, John J. (inventor)

1992-01-01

450

Increasing the Cryogenic Toughness of Steels  

NASA Technical Reports Server (NTRS)

Grain-refining heat treatments increase toughness without substantial strength loss. Five alloys selected for study, all at or near technological limit. Results showed clearly grain sizes of these alloys refined by such heat treatments and grain refinement results in large improvement in toughness without substantial loss in strength. Best improvements seen in HP-9-4-20 Steel, at low-strength end of technological limit, and in Maraging 200, at high-strength end. These alloys, in grain refined condition, considered for model applications in high-Reynolds-number cryogenic wind tunnels.

Rush, H. F.

1986-01-01

451

Cryogenic Active Magnetic Regenerator Test Apparatus  

NASA Astrophysics Data System (ADS)

An AMR Test Apparatus (AMRTA) used in experiments near room-temperature required a number of modifications to allow for testing at cryogenic temperatures and with a 5 T magnetic field. The impacts of parasitic heat leaks, frictional heat generation, and eddy current heating in the AMRTA are analyzed. A low temperature gas circulation (LTGC) system to control the operating temperature was developed. The LTGC consists of a GM cryocooler coupled to a compressor and helium circuit which circulates fluid through a set of heat exchangers and flexible transfer lines connected to the AMRTA. Design features are discussed as is some initial test data.

Tura, A.; Roszmann, J.; Dikeos, J.; Rowe, A.

2006-04-01

452

Geysering inhibitor for vertical cryogenic transfer piping  

NASA Technical Reports Server (NTRS)

Geysering (i.e., the expulsion of boiling liquid and its vapor from a vertical tube) has been a problem for the missile industry in long vertical cryogenic propellant feed lines connecting the launch vehicle propellant tank with the rocket engines. A proposed novel method of inhibiting geysering and the associated pressure gradients provides a self-starting self-regulating action that is not dependent on other active systems or components. The inhibiting action is attained by incorporating a concentric tube within the main transfer tube to prevent constriction of natural convective flow.

Howard, F. S.

1973-01-01

453

CESAR: Cryogenic Electronics for Space Applications  

NASA Astrophysics Data System (ADS)

Ultra-low temperature sensors provide unprecedented performances in X-ray and far infrared astronomy by taking advantage of physical properties of matter close to absolute zero. CESAR is an FP7 funded project started in December 2010, that gathers six European laboratories around the development of high performances cryogenic electronics. The goal of the project is to provide far-IR, X-ray and magnetic sensors with signal-processing capabilities at the heart of the detectors. We present the major steps that constitute the CESAR work, and the main results achieved so far.

Revéret, V.; de la Broïse, X.; Fermon, C.; Pannetier-Lecoeur, M.; Pigot, C.; Rodriguez, L.; Sauvageot, J.-L.; Jin, Y.; Marnieros, S.; Bouchier, D.; Putzeys, J.; Long, Y.; Kiss, C.; Kiraly, S.; Barbera, M.; Lo Cicero, U.; Brown, P.; Carr, C.; Whiteside, B.

2014-08-01

454

Sizing an emergency venting system for a cryogenic dewar  

NASA Technical Reports Server (NTRS)

If the vacuum vessel that insulates a cryogenic dewar for a spaceborne experiment prior to launch is damaged, air will leak into the vacuum insulation space. As the sudden heat load causes the pressure to rise in the dewar, a safety disk in the emergency vent line will burst at the design pressure differential to allow vaporized cryogenic fluid to escape. The emergency vent line should be sized such that sufficient gaseous cryogen will be vented to keep the pressure inside the dewar below the design limit. On the other hand, the line should not be so large as to impose an unnecessary heat load on the dewar filled with cryogenic fluid. A vent-line computer program was generated to compute the maximum flow rate allowed for a proposed vent-line system. Parametric studies have been carried out for different burst disk pressure differentials, liquid cryogen ullage, and vent-line sizes.

Liu, C. K.; Naes, L. G.; Manikowski, A. F., Jr.

1986-01-01

455

Radiation Requirements and Testing of Cryogenic Thermometers for the Ilc  

NASA Astrophysics Data System (ADS)

Large quantity of cryogenic temperature sensors will be used for operation of the International Linear Collider (ILC). Most of them will be subject to high radiation doses during the accelerator lifetime. Understanding of particle energy spectra, accumulated radiation dose in thermometers and its impact on performance are vital in establishing technical specification of cryogenic thermometry for the ILC. Realistic MARS15 computer simulations were performed to understand the ILC radiation environment. Simulation results were used to establish radiation dose requirements for commercially available cryogenic thermometers. Two types of thermometers, Cernox® and TVO, were calibrated prior to irradiation using different technique. The sensors were subjected then to up to 200 kGy electron beam irradiation with kinetic energy of 5 MeV, a representative of the situation at the ILC operation. A post-irradiation behavior of the sensors was studied. The paper describes the MARS15 model, simulation results, cryogenic test set-up, irradiation tests, and cryogenic test results.

Barnett, T.; Filippov, Yu. P.; Filippova, E. Yu.; Mokhov, N. V.; Nakao, N.; Klebaner, A. L.; Korenev, S. A.; Theilacker, J. C.; Trenikhina, J.; Vaziri, K.

2008-03-01

456

Evacuation time of cryogenic pipes for superconducting power transmission  

NASA Astrophysics Data System (ADS)

The vacuum insulation has been used for the thermal insulation of cryogenic pipes for the superconducting power transmission to reduce the heat leak from the environment at the room temperature to the low temperature parts. Since the cryogenic pipes, in particular, those for long distance power transmission, are considered to be thin long pipes, it might take a long time for evacuation. To estimate the evacuation time of the long cryogenic pipes, model calculations have been performed. According to the calculations, it is found that there is an optimum condition between the pumping speed, the diameter of the outer pipe and the length of the cryogenic pipe for efficient evacuation. It is also found that, if the outgassing is suppressed enough, the evacuation can be possible within 1 week even for the long cryogenic pipe with the length of 10 km. The reduction of outgassing is particularly important for the efficient evacuation.

Watanabe, Hirofumi; Sun, Jian; Yamamoto, Norimasa; Hamabe, Makoto; Kawahara, Toshio; Yamaguchi, Satarou

2013-11-01

457

Cryogenic Insulation Bondline Studies for Reusable Launch Vehicles  

NASA Technical Reports Server (NTRS)

Cryogenic insulations bonded to metallic substrates were characterized under simulated mission conditions representative for a reusable launch vehicle. The combined thermal and mechanical test consisted of 50 to a 100 cycles. These combined thermal and mechanical cycles simulated flight missions with temperatures ranging from -423 F to 450 F and a maximum mechanical tension load ranging from 20,000 lbs. to 97,650 lbs. The combined thermal and mechanical (uniaxial tension) test apparatus (1 ft. by 2 ft. Test Apparatus) developed at the NASA Langley Research Center, was used to perform cyclic tests on cryogenic insulations bonded to tank wall substrates. No visual delamination or degradation was observed in the cryogenic insulation-to-metallic substrate bondline or butt joints between cryogenic insulation panels. In addition, after cyclic testing was performed, residual property results from tension-pull and closed-cell content tests of the cryogenic insulations indicated a decrease in the bondline strength and closed-cell content.

Johnson, T. F.; Weiser, E. S.; Duong, P. G.

2003-01-01

458

THz quantum cascade lasers for operation above cryogenic temperatures  

NASA Astrophysics Data System (ADS)

High temperature operation of terahertz (THz) sources based on quantum cascade lasers (QCLs) is discussed. THz QCLs are compact, powerful sources but can only operate at cryogenic temperatures. State-of-the art THz QCLs are made with GaAs/AlGaAs heterostructures and use a single composition of AlGaAs for the barrier material. It was recently shown that multi-composition barriers in the band structure can result in gain > loss at temperature as high as ~240K. We demonstrate early experimental results that yield QCLs that operate up to 184K - similar to QCLs based on single composition barrier designs. An alternative method of producing room-temperature THz is based on intra-cavity difference-frequency generation (DFG) in mid-infrared (mid-IR) QCLs. Here we report devices with record conversion efficiency. THz DFG QCLs reported previously are highly inefficient since THz radiation produced more than ~100 ?m away from the exit facet is fully absorbed due to high THz losses in the QCL waveguide. Our lasers use a non-collinear Cherenkov DFG scheme to extract THz radiation from the active region. Dual-color mid-IR quantum cascade lasers with integrated giant optical nonlinearity are grown on semi-insulating (S.I.) InP substrates. THz radiation is emitted at an angle into the substrate with respect to the mid-infrared pumps. Since S.I. InP is virtually lossless to THz radiation, this scheme allows for efficient extraction of THz radiation along the whole waveguide length. As a result, our sources demonstrate large mid-infrared-to-THz conversion efficiency. Devices tested at room-temperature produced 18?W peakpower and 75?W/W2 conversion efficiency.

Belkin, M. A.; Vijayraghavan, K.; Vizbaras, A.; Jiang, A.; Demmerle, F.; Boehm, G.; Meyer, R.; Amann, M.-C.; Matyas, A.; Chashmahcharagh, R.; Lugli, P.; Jirauschek, C.; Wasilewski, Z. R.

2013-03-01

459

Daydreaming Devices  

E-print Network

Daydreaming Devices is a project on aspects of daydream and the design of convertible furniture within the context of art. This thesis addresses the concepts and the design of two daydreaming devices developed during my ...

Da Ponte, Ana Sofia Lopes

2008-01-01

460

Cryogenic Fluid Management Technology for Moon and Mars Missions  

NASA Technical Reports Server (NTRS)

In support of the U.S. Space Exploration Policy, focused cryogenic fluid management technology efforts are underway within the National Aeronautics and Space Administration. Under the auspices of the Exploration Technology Development Program, cryogenic fluid management technology efforts are being conducted by the Cryogenic Fluid Management Project. Cryogenic Fluid Management Project objectives are to develop storage, transfer, and handling technologies for cryogens to support high performance demands of lunar, and ultimately, Mars missions in the application areas of propulsion, surface systems, and Earth-based ground operations. The targeted use of cryogens and cryogenic technologies for these application areas is anticipated to significantly reduce propellant launch mass and required on-orbit margins, to reduce and even eliminate storage tank boil-off losses for long term missions, to economize ground pad storage and transfer operations, and to expand operational and architectural operations at destination. This paper organizes Cryogenic Fluid Management Project technology efforts according to Exploration Architecture target areas, and discusses the scope of trade studies, analytical modeling, and test efforts presently underway, as well as future plans, to address those target areas. The target areas are: liquid methane/liquid oxygen for propelling the Altair Lander Ascent Stage, liquid hydrogen/liquid oxygen for propelling the Altair Lander Descent Stage and Ares V Earth Departure Stage, liquefaction, zero boil-off, and propellant scavenging for Lunar Surface Systems, cold helium and zero boil-off technologies for Earth-Based Ground Operations, and architecture definition studies for long term storage and on-orbit transfer and pressurization of LH2, cryogenic Mars landing and ascent vehicles, and cryogenic production via in situ resource utilization on Mars.

Doherty, Michael P.; Gaby, Joseph D.; Salerno, Louis J.; Sutherlin, Steven G.

2010-01-01

461

Advances in cryogenic engineering. Volume 27 - Proceedings of the Cryogenic Engineering Conference, San Diego, CA, August 11-14, 1981  

NASA Astrophysics Data System (ADS)

Applications of superconductivity are considered, taking into account MHD and fusion, generators, transformers, transmission lines, magnets for physics, cryogenic techniques, electrtronics, and aspects of magnet stability. Advances related to heat transfer in He I are discussed along with subjects related to theat transfer in He II, refrigeration of superconducting systems, refrigeration and liquefaction, dilution and magnetic refrigerators, refrigerators for space applications, mass transfer and flow phenomena, and the properties of fluids. Developments related to cryogenic applications are also explored, giving attention to bulk storage and transfer of cryogenic fluids, liquefied natural gas operations, space science and technology, and cryopumping. Topics related to cryogenic instrumentation and controls include the production and use of high grade silicon diode temperature sensors, the choice of strain gages for use in a large superconducting alternator, microprocessor control of cryogenic pressure, and instrumentation, data acquisition and reduction for a large spaceborne helium dewar. For individual items see A83-43221 to A83-43250

Fast, R. W.

462

Narrow bandpass cryogenic filter for microwave measurements  

NASA Astrophysics Data System (ADS)

An ultra-wide stopband hairpin bandpass filter with integrated nonuniform transmission lines was designed and fabricated for highly sensitive measurements at cryogenic temperatures down to millikelvin and a frequency range of 10 Hz-10 GHz. The scattering matrices of the filter were characterized at T = 4.2 K. The filter provides a stopband from 10 Hz to 2.2 GHz and from 2.3 GHz to 10 GHz with more than 50 dB and 40 dB of amplitude suppression, respectively. The center frequency of the passband is f0 = 2.25 GHz with a bandwidth ?f = 80 MHz. The maximum insertion loss in the passband is 4 dB. The filter has a 50 ? input and output impedance, SubMiniature version A connector termination, and significantly reduced form factor. The wide stopband frequency range and narrow passband in conjunction with small dimensions make the filter suitable to use it as a part of a high sensitive readout for superconducting quantum circuits, such as superconducting quantum bits and cryogenic parametric amplifiers.

Ivanov, B. I.; Klimenko, D. N.; Sultanov, A. N.; Il'ichev, E.; Meyer, H.-G.

2013-05-01

463

Cryogenic current-in-plane tunneling apparatus.  

PubMed

We have designed and fabricated a cryogenic variable-temperatu