Note: This page contains sample records for the topic cryogenic devices from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: August 15, 2014.
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) [Yorktown, VA; Phillips, Harry Lawrence (Hayes, VA) [Hayes, VA

2008-12-30

3

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

4

Novel SiGe Semiconductor Devices for Cryogenic Power Electronics  

Microsoft Academic Search

It is predicted that systems for electrical power generation, conversion and distribution on ships and aerospace vehicles could be made smaller, lighter, more efficient, more versatile, and lower maintenance by operating these systems-partly or entirely-at cryogenic temperatures. In view of this, we have taken initial steps in the investigation and development of SiGe semiconductor devices for cryogenic power applications. We

R. R. Ward; W. J. Dawson; L. Zhu; R. K. Kirschman; G. Niu; R. M. Nelms; O. Mueller; M. J. Hennessy; E. K. Mueller

2006-01-01

5

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

6

Cryogenically cooled HEMT's from the device towards the applications  

Microsoft Academic Search

The essential low temperature electrical characteristics of HEMT devices are presented. The emphasis is put on practical aspects of prime importance for the circuit designer such as the collapse preventing techniques or the noise behaviour. Some examples of cryogenic analog circuits are then described with their performances compared to their ambient temperature counterparts

O. Llopis; L. Escotte

1995-01-01

7

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

8

On-wafer, cryogenic characterization of ultra-low noise HEMT devices  

NASA Technical Reports Server (NTRS)

Significant advances in the development of high electron-mobility field-effect transistors (HEMT's) have resulted in cryogenic, low-noise amplifiers (LNA's) whose noise temperatures are within an order of magnitude of the quantum noise limit (hf/k). Further advances in HEMT technology at cryogenic temperatures may eventually lead to the replacement of maser and superconducting insulator superconducting front ends in the 1- to 100-GHz frequency band. Key to identification of the best HEMT's and optimization of cryogenic LNA's are accurate and repeatable device measurements at cryogenic temperatures. This article describes the design and operation of a cryogenic coplanar waveguide probe system for the characterization and modeling of advanced semiconductor transistors at cryogenic temperatures. Results on advanced HEMT devices are presented to illustrate the utility of the measurement system.

Bautista, J. J.; Laskar, J.; Szydlik, P.

1995-01-01

9

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

10

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

11

Nano-Strip Three-Terminal Superconducting Device for Cryogenic Detector Readout  

Microsoft Academic Search

A superconducting 3-terminal device based on NbN ultra-thin nano-strips has been realized. The device is capable of pulse discrimination and shaping and provides power gain with standard 50 input and output impedance. It operates at 4.2 K and is well suited for the realization of output interfaces for su- perconducting digital circuits and as readout of cryogenic detec- tors.Successfulrealizationoftheintegratedreadoutofanano-strip single

Sergio Pagano; Nadia Martucciello; Roberto Cristiano; Mikkel Ejrnaes; Alessandro Casaburi; Roberto Leoni; Alessandro Gaggero; Francesco Mattioli; Jean Claude Villegier; Paul Cavalier

2011-01-01

12

S-Parameter, IV Curve and Noise Figure Measurements of IIIV Devices at Cryogenic Temperatures  

Microsoft Academic Search

We have measured the electrical operating parameters for several three-terminal semiconductor III-V devices at both room temperature and liquid nitrogen temperature, 80 K. The fundamental performance parameters, I-V curve, S-parameters and noise figure, change quite dramatically upon cooling. It is necessary to know these parameters if an optimal cryogenic device, e.g. high-temperature superconducting\\/III-V hybrid, is to be designed and fabricated.

Charles Wilker; Philip S. W. Pang; Charles F. Carter; Zhi-Yuan Shen

1992-01-01

13

Fiber-coupled photoconductive sampling for time-resolved transport measurements of cryogenic devices  

NASA Astrophysics Data System (ADS)

Photoconductive sampling can measure both the amplitude and phase components of the impulse response of cryogenic mesoscopic devices on a picosecond time scale. Mesoscopic devices that operate at temperatures < 1 K are difficult to measure because of constraints on the maximum tolerable thermal loading through optical windows that pass the optical pulses required to drive the photoconductive switches. We have developed a new technique that avoids using optical windows altogether. Two short lengths of optical fiber are pigtailed to the photoconductive switches and couple picosecond optical pulses through the walls of the cryostat. The photoconductive switches have meandered active areas that were defined by electron beam lithography. The system has been operated at liquid helium temperatures using < 1 mW of average optical power, with a time resolution of 5 picoseconds. Preliminary efforts in measuring cryogenic three terminal devices will be discussed. ^Also at MIT Lincoln Laboratory, Lexington MA.

Verghese, S.; Zamdmer, N.; Hu, Q.; Förster, A.

1996-03-01

14

Electrical performance of semiconductor devices at cryogenic temperatures  

NASA Technical Reports Server (NTRS)

The electrical performance of semiconductor devices is examined over the temperature range from 300 to 1.4K The design, fabrication, and testing of p-channel field effective transistors (MOSFET) are emphasized to develop a device that will perform satisfactorily in the temperature range from 4.2 to 1.4K. The current-voltage characteristics of the device are obtained as a function of temperature for varying channel lengths and channel dopant levels. The MOSFET's with average channel lengths of 3.27, 5.68, 8.37, and 11.39 microns are examined. It is indicated that the devices with the shorter channel lengths perform better in the 4 to 20K range than those with the longer channel lengths.

Ventrice, C. A.

1985-01-01

15

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

NASA Astrophysics Data System (ADS)

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.; Gopman, D. B.; Rehm, L.; Backes, D.; Wolf, G.; Ohki, T.; Kirichenko, A. F.; Vernik, I. V.; Mukhanov, O. A.; Kent, A. D.

2014-05-01

16

Do-It-Yourself Device for Recovery of Cryopreserved Samples Accidentally Dropped into Cryogenic Storage Tanks  

PubMed Central

Liquid nitrogen is colorless, odorless, extremely cold (-196 °C) liquid kept under pressure. It is commonly used as a cryogenic fluid for long term storage of biological materials such as blood, cells and tissues 1,2. The cryogenic nature of liquid nitrogen, while ideal for sample preservation, can cause rapid freezing of live tissues on contact - known as 'cryogenic burn'2, which may lead to severe frostbite in persons closely involved in storage and retrieval of samples from Dewars. Additionally, as liquid nitrogen evaporates it reduces the oxygen concentration in the air and might cause asphyxia, especially in confined spaces2. In laboratories, biological samples are often stored in cryovials or cryoboxes stacked in stainless steel racks within the Dewar tanks1. These storage racks are provided with a long shaft to prevent boxes from slipping out from the racks and into the bottom of Dewars during routine handling. All too often, however, boxes or vials with precious samples slip out and sink to the bottom of liquid nitrogen filled tank. In such cases, samples could be tediously retrieved after transferring the liquid nitrogen into a spare container or discarding it. The boxes and vials can then be relatively safely recovered from emptied Dewar. However, the cryogenic nature of liquid nitrogen and its expansion rate makes sunken sample retrieval hazardous. It is commonly recommended by Safety Offices that sample retrieval be never carried out by a single person. Another alternative is to use commercially available cool grabbers or tongs to pull out the vials3. However, limited visibility within the dark liquid filled Dewars poses a major limitation in their use. In this article, we describe the construction of a Cryotolerant DIY retrieval device, which makes sample retrieval from Dewar containing cryogenic fluids both safe and easy.

Mehta, Rohini; Baranova, Ancha; Birerdinc, Aybike

2012-01-01

17

Micromachined cryogenic cooler for cooling electronic devices down to 30 K  

NASA Astrophysics Data System (ADS)

Cryogenic temperatures are required for improving the performance of electronic devices and for operating superconducting sensors and circuits. The broad implementation of cooling these devices has long been constrained by the availability of reliable and low cost cryocoolers. After the successful development of single-stage micromachined coolers able to cool to 100 K, we now present a micromachined two-stage microcooler that cools down to 30 K from an ambient temperature of 295 K. The first stage of the microcooler operates at about 94 K with nitrogen gas and pre-cools the second stage operating with hydrogen gas. The microcooler is made from just three glass wafers and operates with modest high-pressure gases and without moving parts facilitating high yield fabrication of these microcoolers. We have successfully cooled a YBCO film through its superconducting transition state to demonstrate a load on the microcooler at cryogenic temperatures. This work could expedite the application of superconducting and electronic sensors and detectors among others in medical and space applications.

Cao, H. S.; Holland, H. J.; Vermeer, C. H.; Vanapalli, S.; Lerou, P. P. P. M.; Blom, M.; ter Brake, H. J. M.

2013-02-01

18

Thermal expansion of blood vessels in low cryogenic temperatures Part I: A new experimental device  

PubMed Central

As part of the ongoing effort to study the mechanical behavior of biological material during cryopreservation processes, the current study focuses on thermal expansion of blood vessels at low cryogenic temperatures. The current paper (Part I) describes a new experimental device for thermal expansion measurements of blood vessels in typical conditions of vitrification, which are associated with rapid cooling rates. For validation purposes, the thermal strain of frozen arteries in the absence of cryoprotectants was measured, and found to be about 10% larger than that of polycrystalline water; this observation agrees with literature data. The companion paper (Part II) reports on experimental results of cryoprotectants permeated with VS55, DP6 and 7.05M DMSO at high cooling rates applicable to vitrification.

Jimenez Rios, Jorge L.; Rabin, Yoed

2006-01-01

19

Thermal expansion of blood vessels in low cryogenic temperatures Part I: A new experimental device.  

PubMed

As part of the ongoing effort to study the mechanical behavior of biological material during cryopreservation processes, the current study focuses on thermal expansion of blood vessels at low cryogenic temperatures. The current paper (Part I) describes a new experimental device for thermal expansion measurements of blood vessels in typical conditions of vitrification, which are associated with rapid cooling rates. For validation purposes, the thermal strain of frozen arteries in the absence of cryoprotectants was measured, and found to be about 10% larger than that of polycrystalline water; this observation agrees with literature data. The companion paper (Part II) reports on experimental results of cryoprotectants permeated with VS55, DP6, and 7.05 M DMSO at high cooling rates applicable to vitrification. PMID:16487503

Jimenez Rios, Jorge L; Rabin, Yoed

2006-04-01

20

Low-noise cryogenic X-band amplifier using wet-etched hydrogen passivated InP HEMT devices  

Microsoft Academic Search

The performance of a cryogenically cooled X-band amplifier for the geodetic VLBI X-band (8.1-9.0 GHz) is presented. The amplifier incorporates hydrogen passivated InP devices with 0.2×200 ?m gate. A comparison of the noise performance with selected commercially available GaAs high electron mobility transistor (HEMT) devices of similar dimensions is presented. The InP amplifier shows lower noise temperature (Tn=4.8 K, NF=0.07

Isaac Lopez-Fernandez; Juan Daniel Gallego Puyol; Otte J. Homan; Alberto Barcia Cancio

1999-01-01

21

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

22

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

23

A New Device for Mechanical Testing of Blood Vessels at Cryogenic Temperatures  

PubMed Central

As part of an ongoing program to study the thermo-mechanical effects associated with cryopreservation via vitrification (vitreous in Latin means glassy), the current study focuses on the development of a new device for mechanical testing of blood vessels at cryogenic temperatures. This device is demonstrated on a bovine carotid artery model, permeated with the cryoprotectant cocktail VS55 and a reference solution of 7.05M DMSO, below glass transition. Results are also presented for crystallized specimens, in the absence of cryoprotectants. Results indicate that the elastic modulus of a specimen with no cryoprotectant, at about ?140°C (8.6°C and 15.5°C below the glass transition temperature of 7.05M DMSO and VS55, respectively), is 1038.8 ± 25.2 MPa, which is 8% and 3% higher than that of a vitrified specimen permeated with 7.05M DMSO and VS55, respectively. The elastic modulus of a crystallized material at ?50°C is lower by ~20% lower from that at ?140°C.

Jimenez Rios, Jorge L.; Rabin, Yoed

2008-01-01

24

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

25

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

26

The Cryogenic DC Behavior of Cryo3/AZ1 InP 0.1-by-80-Micrometer-Gate High Electron Mobility Transistor Devices  

NASA Astrophysics Data System (ADS)

We have examined the cryogenic DC behavior of 80-micrometer-gate-width devices from the "Cryo3/AZ1" wafer lot. Our measurements indicate that transistors from all five wafers have good "quality of pinch-off." The gate-source leakage current and excess gate current have been investigated. All measured devices exhibited memory in the bias behavior at cryogenic temperatures. Illumination of the devices tends to make them more well-behaved. The effect of voltage stress and light on the turn-on voltage of a device from the -041 wafer has been investigated. A weak persistence of the effect of bias stress is also observed.

Shell, J.

2007-05-01

27

Atomic layer deposition enhanced rapid dry fabrication of micromechanical devices with cryogenic deep reactive ion etching  

Microsoft Academic Search

A fast, dry microfabrication process combining atomic layer deposition, electron beam lithography and cryogenic deep reactive ion etching is presented. The process exploits the extremely high selectivity of atomic layer deposited amorphous Al2O3 (alumina) to silicon in cryogenic etching by using an ultra-thin (t <= 5nm) Al2O3 film as a mask. The process rules and limitations are carefully analyzed and

N. Chekurov; M. Koskenvuori; V.-M. Airaksinen; I. Tittonen

2007-01-01

28

0.1 ?m InP HEMT devices and MMICs for cryogenic low noise amplifiers from X-band to W-band  

Microsoft Academic Search

We present the TRW 0.1 ?m InP HEMT MMIC production technology that has been developed and used for state-of-the-art cryogenic LNA applications. The 0.1 ?m InP HEMT devices typically show cutoff frequency above 200 GHz and transconductance above 1000 mS\\/mm. Aspects of device design and fabrication are presented which impact important parameters including the InP HEMT device gain, gate leakage

R. Grundbacher; R. Lai; M. Barsky; R. Tsai; T. Gaier; S. Weinreb; D. Dawson; J. J. Bautista; J. F. Davis; N. Erickson; T. Block; A. Oki

2002-01-01

29

A cryogen-free refrigerating preconcentration device for the measurement of C2 to C4 hydrocarbons in ambient air.  

PubMed

A cryogen-free refrigerating preconcentration device for the enrichment of trace amounts of highly volatile organic compounds in the atmosphere prior to analysis has been designed and evaluated. The device consists of a microtrap housed in an insulated box, which is cooled by a conventional refrigeration unit. Experimental parameters, including adsorbent mass, trapping temperature, and thermal desorption temperature, were optimized. The on-line coupling of the device to a GC allows sufficient enrichment and separation of C2 to C4 hydrocarbons in less than 40 min without a second cryotrap. The target compounds analysis showed good linearity (correlation coefficients >0.99) and repeatability (relative standard deviation <5%). Detection limits for the 10 volatile organic compounds ranged from 14 ppt to 52 ppt, under the conditions of a 500 mL sampling volume and -10 °C trapping temperature. Real air sample measurements were conducted at an urban site, and five VOCs including ethane, ethene, propane, propene and 1-butene were detected and quantified. PMID:21076785

Peng, Hong; Wang, Jianwei; Shen, Zheng; Wu, Dapeng; Guan, Yafeng

2011-02-01

30

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

31

CRYOGENICS IN BEPCII UPGRADE.  

SciTech Connect

THIS PAPER PRESENTS A CRYOGENIC DESIGN FOR UPGRADING THE BEIJING ELECTRON POSITRON COLLIDER AT THE INSTITUTE OF HIGH ENERGY PHYSICS IN BEIJING. THE UPGRADE INVOLVES 3 NEW SUPERCONDUCTING FACILITIES, THE INTERACTION REGION QUADRUPOLE MAGNETS, THE DETECTOR SOLENOID MAGNETS AND THE SRF CAVITIES. FOR COOLING OF THESE DEVICES, A NEW CRYPLANT WITH A TOTAL CAPACITY OF 1.0KW AT 4.5K IS TO BE BUILT AT IHEP. AN INTEGRATED CRYOGENIC DESIGN TO FIT THE BEPCII CRYOGENIC LOADS WITH HIGH EFFICIENCY IS CARRIEDOUT USING COMPUTATIONAL PROCESS ANALYSIS SOFTWARE WITH THE EMPHASES ON ECONOMICS AND SAFETY IN BOTH CONSTRUCTION AND OPERATION OF THE PLANT. THIS PAPER DESCRIBES THE CRYOGENIC CHARACTERISTICS OF EACH SUPERCONDUCTING DEVICE, THEIR COOLING SCHEMES AND THE OVERALL CRYOPLANT.

JIA,L.; WANG,L.; LI,S.

2002-07-22

32

Cooling of superconducting devices by liquid storage and refrigeration unit  

SciTech Connect

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

33

Cryogenic ion implantation near amorphization threshold dose for halo/extension junction improvement in sub-30 nm device technologies  

SciTech Connect

We report on junction advantages of cryogenic ion implantation with medium current implanters. We propose a methodical approach on maximizing cryogenic effects on junction characteristics near the amorphization threshold doses that are typically used for halo implants for sub-30 nm technologies. BF{sub 2}{sup +} implant at a dose of 8 Multiplication-Sign 10{sup 13}cm{sup -2} does not amorphize silicon at room temperature. When implanted at -100 Degree-Sign C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF{sub 2}{sup +} implant significantly reduces the depth of the boron distribution, both as-implanted and after anneals, which improves short channel rolloff characteristics. It also creates a shallower n{sup +}-p junction by steepening profiles of arsenic that is subsequently implanted in the surface region. We demonstrate effects of implant sequences, germanium preamorphization, indium and carbon co-implants for extension/halo process integration. When applied to sequences such as Ge+As+C+In+BF{sub 2}{sup +}, the cryogenic implants at -100 Degree-Sign C enable removal of Ge preamorphization, and form more active n{sup +}-p junctions and steeper B and In halo profiles than sequences at room temperature.

Park, Hugh; Todorov, Stan; Colombeau, Benjamin; Rodier, Dennis; Kouzminov, Dimitry; Zou Wei; Guo Baonian; Khasgiwale, Niranjan; Decker-Lucke, Kurt [Applied Materials, Varian Semiconductor Equipment, 35 Dory Road, Gloucester, Massachusetts 01930 (United States)

2012-11-06

34

Modeling the temperature noisy performance of low-noise III-V microwave devices down to cryogenic levels  

Microsoft Academic Search

We performed research work on the effects of temperature by investigating the, DC behavior, the small signal and the noise performance of HEMT and HBT at microwave frequencies by means of different experimental systems down to cryogenic levels. The measurement data were then employed to extract temperature-dependent noisy models to be implemented in commercial CAD software. Here we report the

A. Caddemi; N. Donato; G. Tuccari

2001-01-01

35

Cryogenics Safety.  

National Technical Information Service (NTIS)

The safety hazards associated with handling cryogenic fluids are discussed in detail. These hazards include pressure buildup when a cryogenic fluid is heated and becomes a gas, potential damage to body tissues due to surface contact, toxic risk from breat...

R. Reider

1977-01-01

36

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

37

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

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

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

40

Cryogenic Pound Circuits for Cryogenic Sapphire Oscillators  

NASA Technical Reports Server (NTRS)

Two modern cryogenic variants of the Pound circuit have been devised to increase the frequency stability of microwave oscillators that include cryogenic sapphire-filled cavity resonators. The original Pound circuit is a microwave frequency discriminator that provides feedback to stabilize a voltage-controlled microwave oscillator with respect to an associated cavity resonator. In the present cryogenic Pound circuits, the active microwave devices are implemented by use of state-of-the-art commercially available tunnel diodes that exhibit low flicker noise (required for high frequency stability) and function well at low temperatures and at frequencies up to several tens of gigahertz. While tunnel diodes are inherently operable as amplitude detectors and amplitude modulators, they cannot, by themselves, induce significant phase modulation. Therefore, each of the present cryogenic Pound circuits includes passive circuitry that transforms the AM into the required PM. Each circuit also contains an AM detector that is used to sample the microwave signal at the input terminal of the high-Q resonator for the purpose of verifying the desired AM null at this point. Finally, each circuit contains a Pound signal detector that puts out a signal, at the modulation frequency, having an amplitude proportional to the frequency error in the input signal. High frequency stability is obtained by processing this output signal into feedback to a voltage-controlled oscillator to continuously correct the frequency error in the input signal.

Dick, G. John; Wang, Rabi

2006-01-01

41

Broad-band Cryogenic Microwave Filtering Scheme for Operating Devices at Sub 0.1 Kelvin Temperatures  

Microsoft Academic Search

We developed compact low-pass filters for transport experiments with single-electron devices at temperatures below 0.1 Kelvin. The filter assembly consists of a coil made of a long thin copper wire placed in a chamber filled with stainless still powder. The transmission of the filter at frequencies between 40 MHz and 20 GHz was measured using a Vector Analyzer (Anritsu Lightning)

Kristen Herrmann; Andrei Kogan

2007-01-01

42

Cryogenic Systems  

NASA Astrophysics Data System (ADS)

In this lecture we discuss the principle of method of cooling to a very low temperature, i.e. cryogenic. The "gas molecular model" will be introduced to explain the mechanism cooling by the expansion engine and the Joule-Thomson expansion valve. These two expansion processes are normally used in helium refrigeration systems to cool the process gas to cryogenic temperature. The reverse Carnot cycle will be discussed in detail as an ideal refrigeration cycle. First the fundamental process of liquefaction and refrigeration cycles will be discussed, and then the practical helium refrigeration system. The process flow of the system and the key components; -compressor, expander, and heat exchanger- will be discussed. As an example of an actual refrigeration system, we will use the cryogenic system for the KEKB superconducting RF cavity. We will also discuss the liquid helium distribution system, which is very important, especially for the cryogenic systems used in accelerator applications. 1 Principles of Cooling and Fundamental Cooling Cycle 2 Expansion engine, Joule-Thomson expansion, kinetic molecular theory, and enthalpy 3 Liquefaction Systems 4 Refrigeration Systems 5 Practical helium liquefier/refrigeration system 6 Cryogenic System for TRISTAN Superconducting RF Cavity

Hosoyama, Kenji

2002-02-01

43

Cryogenic electrolytes  

NASA Astrophysics Data System (ADS)

Experimental evidence of metastable ion dipoles in solid helium is examined. Similar quasiparticles with positive scattering lengths for injected electrons are assumed to exist in the liquid phases of cryogenic liquids. Phenomena that can be used for detecting and monitoring a dipole gas in superfluid helium (referred to as cryogenic electrolyte) are discussed. The most interesting of these phenomena are: special features of the dielectric behavior of ion dipole gases, the temperature dependence of the ion dipole gas osmotic pressure at the boundary of liquid 3He-4He solution stratification, relaxation phenomena of collective origin in cryogenic electrolytes, and the transformation of the phonon spectrum of liquid helium owing to strong interactions between phonons and heavy dipole quasiparticles.

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

2013-05-01

44

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

45

Cryogenic regenerator  

SciTech Connect

The regenerator for a cryogenic system has lead sphere packing and has grooves in the regenerator walls to prevent gas bypass. Felt packing between the screens causes continued compression of the regenerator packing as it changes size due to temperature changes. Gas spaces between the regenerator spheres is maintained low and regenerator sphere damage due to high intersphere loading is minimized.

Lagodmos, G.P.

1980-11-04

46

Dual Cryogenic Capacitive Density Sensor  

NASA Technical Reports Server (NTRS)

A dual cryogenic capacitive density sensor has been developed. The device contains capacitive sensors that monitor two-phase cryogenic flow density to within 1% accuracy, which, if temperature were known, could be used to determine the ratio of liquid to gas in the line. Two of these density sensors, located a known distance apart, comprise the sensor, providing some information on the velocity of the flow. This sensor was constructed as a proposed mass flowmeter with high data acquisition rates. Without moving parts, this device is capable of detecting the density change within a two-phase cryogenic flow more than 100 times a second. Detection is enabled by a series of two sets of five parallel plates with stainless steel, cryogenically rated tubing. The parallel plates form the two capacitive sensors, which are measured by electrically isolated digital electronics. These capacitors monitor the dielectric of the flow essentially the density of the flow and can be used to determine (along with temperature) the ratio of cryogenic liquid to gas. Combining this information with the velocity of the flow can, with care, be used to approximate the total two-phase mass flow. The sensor can be operated at moderately high pressures and can be lowered into a cryogenic bath. The electronics have been substantially improved over the older sensors, incorporating a better microprocessor, elaborate ground loop protection and noise limiting circuitry, and reduced temperature sensitivity. At the time of this writing, this design has been bench tested at room temperature, but actual cryogenic tests are pending

Youngquist, Robert; Mata, Carlos; Vokrot, Peter; Cox, Robert

2009-01-01

47

Cryogenic Insulation  

NASA Technical Reports Server (NTRS)

Kevin Rivers, Thermal Structures Branch, checks electronic wiring on a test panel for a cryogenic insulation system. The thermal-mechanical testing is being done for Lockheed Martin as part of the X-33 Reusable Launch Vehicle (RLV) program. The foam panel, encased in an aluminum alloy, will be subjected to very low and very high temperatures and then be placed under heavyloads as part of the testing. Material in this panel may be used as part of an RLV fuel tank.

1996-01-01

48

Cryogenic Treatment Database  

NSDL National Science Digital Library

The Cryogenics Database is a website created by the Cryogenic Society of America that contains "scientific and informational articles pertaining to the cryogenic treatment industry", and is updated quarterly. Visitors curious about cryogenics, but only aware of the "misinformation about cryogenic treatment of materials in the public domain" can become familiar with cryogenics by checking out the "Resources" tab, near the top of any page. The "Cryo Central: Cryogenic Treatment of Materials" document gives examples of some of the types of raw materials that are treated with cryogenic processing, and their applications in the everyday world. Some of the examples given are brakes, racing cars, stereos, industrial tooling, and sporting goods.

49

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

50

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

51

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

52

Design parameter evaluation of a metal recoated Fiber Bragg Grating sensors for measurement of cryogenic temperature or stress in superconducting devices  

NASA Astrophysics Data System (ADS)

There are plenty of complex physical phenomena which remain to be studied and verified experimentally for building an optimized superconducting magnet. The main problem for experimental validations is due to the unavailability of suitable sensors. This paper proposes a Fiber Bragg Gratings (FBG) sensor for this purpose which allows access to the local temperature/stress state. To measure the low temperature (20 K), FBG can be recoated with materials having high thermal expansion coefficient (HTCE). This can induce a thermal stress for a temperature change, which in turn increases the sensitivity of the sensor. The performance of such sensors has been experimentally studied and reported in earlier paper [Rajinikumar R, Suesser M, Narayankhedkar KG, Krieg G, Atrey MD. Performance evaluation of metallic coated Fiber Bragg Grating sensors for sensing cryogenic temperature. Cryogenics 2008;48:142-7]. This paper aims at evaluation and determination of different design parameters like coating materials, coating thickness, grating period and the grating length for design of better performance FBG sensor for low temperature/stress measurements.

Rajinikumar, R.; Süßer, M.; Narayankhedkar, K. G.; Krieg, G.; Atrey, M. D.

2009-05-01

53

Development of Advanced Tools for Cryogenic Integration  

NASA Astrophysics Data System (ADS)

This paper describes four advanced devices (or tools) that were developed to help solve problems in cryogenic integration. The four devices are: (1) an across-gimbal nitrogen cryogenic loop heat pipe (CLHP) (2) a miniaturized neon CLHP; (3) a differential thermal expansion (DTE) cryogenic thermal switch (CTSW) and (4) a dual-volume nitrogen cryogenic thermal storage unit (CTSU). The across-gimbal CLHP provides a low torque, high conductance solution for gimbaled cryogenic systems wishing to position their cryocoolers off-gimbal. The miniaturized CLHP combines thermal transport, flexibility, and thermal switching (at 35 K) into one device that can be directly mounted to both the cooler cold head and the cooled component. The DTE-CTSW, designed and successfully tested in a previous program using a stainless steel tube and beryllium (Be) end-pieces, was redesigned with a polymer rod and high-purity aluminum (Al) end-pieces to improve performance and manufacturability while still providing a miniaturized design. Lastly, the CTSU was designed with a 6063 Al heat exchanger and integrally welded, segmented, high purity Al thermal straps for direct attachment to both a cooler cold head and a Be component whose peak heat load exceeds its average load by 2.5 times. For each device, the paper will describe its development objective, operating principles, heritage, requirements, design, test data and lessons learned.

Bugby, D. C.; Marland, B. C.; Stouffer, C. J.; Kroliczek, E. J.

2004-06-01

54

Refrigeration for Cryogenic Sensors  

NASA Astrophysics Data System (ADS)

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.

1983-12-01

55

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

56

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

57

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

58

Cryogenic insulation strength and bond tester  

Microsoft Academic Search

A method and apparatus for testing the tensile strength and bonding strength of sprayed-on foam insulation attached to metal cryogenic fuel tanks. 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 electro-mechanical pulling device powered

P. H. Schuerer; J. H. Ehl; W. P. Prasthofer

1985-01-01

59

Cryogenic structural materials for superconducting magnets  

SciTech Connect

This paper reviews research in the United States and Japan on structural materials for high-field superconducting magnets. Superconducting magnets are used for magnetic fusion energy devices and for accelerators that are used in particle-physics research. The cryogenic structural materials that we review are used for magnet cases and support structures. We expect increased materials requirements in the future.

Dalder, E.N.C.; Morris, J.W. Jr.

1985-02-22

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

Cryogenics program overview  

NASA Technical Reports Server (NTRS)

An overview of the cryogenics program of the Goddard Space Flight Center is given in viewgraph form. Goddard's role and the flight programs requiring cryogenics are outlined. Diagrams are given of the Cosmic Background Explorer, the Broad Band X-Ray Telescope, the Hubble Space Telescope, an adiabatic demagnetization refrigerator, a liquid cryogenic cooler for the Shuttle Glow Experiment, a liquid helium dewar, and the X-ray spectrometer on the Advanced X-Ray Astrophysics Facility.

Castles, Stephen H.

1987-01-01

62

Cryogenic Permanent Magnet Undulators  

NASA Astrophysics Data System (ADS)

For an in-vacuum undulator operated at small gaps the permanent magnet material needs to be highly resistant to possible electron beam exposure. At room temperature, one generally uses Sm2Co17 or high coercivity NdFeB magnets at the expense of a limited field performance. In a cryogenic permanent magnet undulator (CPMU), at a temperature of around 150 K, any NdFeB grade reveals a coercivity large enough to be radiation resistant. In particular, very high remanence NdFeB material can be used to build undulators with enhanced field and X-ray brilliance at high photon energy provided that the pre-baking of the undulator above 100 deg. C can be eliminated. The ESRF has developed a full scale 2 m long CPMU with a period of 18 mm. This prototype has been in operation on the ID6 test beamline since January 2008. A significant effort was put into the characterization of NdFeB material at low temperature, the development of dedicated magnetic measurement systems and cooling methods. The measured heat budget with beam is found to be larger than expected without compromising the smooth operation of the device. Leading on from this first experience, new CPMUs are currently being considered for the upgrade of the ESRF.

Chavanne, J.; Lebec, G.; Penel, C.; Revol, F.; Kitegi, C.

2010-06-01

63

Sealing Mechanical Cryogenic Coolers  

NASA Technical Reports Server (NTRS)

Metal bellows used to seal Vuilleumier and Stirling-cycle cryogenic coolers, replacing sliding seals that failed after only 3,000 hours of service. Metal bellows, incorporated in displacer design provide nonrubbing dynamic seal. Lifetime of cryogenic cooler no longer limited by loss of sealing material and by deterioration of regenerators due to clogging by seal debris.

Richter, R.

1985-01-01

64

Cryogenic Information Center  

NASA Technical Reports Server (NTRS)

The Cryogenic Information Center (CIC) is a not-for-profit corporation dedicated to preserving and distributing cryogenic information to government, industry, and academia. The heart of the CIC is a uniform source of cryogenic data including analyses, design, materials and processes, and test information traceable back to the Cryogenic Data Center of the former National Bureau of Standards. The electronic database is a national treasure containing over 146,000 specific bibliographic citations of cryogenic literature and thermophysical property data dating back to 1829. A new technical/bibliographic inquiry service can perform searches and technical analyses. The Cryogenic Material Properties (CMP) Program consists of computer codes using empirical equations to determine thermophysical material properties with emphasis on the 4-300K range. CMP's objective is to develop a user-friendly standard material property database using the best available data so government and industry can conduct more accurate analyses. The CIC serves to benefit researchers, engineers, and technologists in cryogenics and cryogenic engineering, whether they are new or experienced in the field.

Mohling, Robert A.; Marquardt, Eric D.; Fusilier, Fred C.; Fesmire, James E.

2003-01-01

65

Cryogenics Program Overview.  

National Technical Information Service (NTIS)

An overview of the cryogenics program of the Goddard Space Flight Center is given in viewgraph form. Goddard's role and the flight programs requiring cryogenics are outlined. Diagrams are given of the Cosmic Background Explorer, the Broad Band X-Ray Teles...

S. H. Castles

1987-01-01

66

Cryogenic Probe Station for Use in Automated Microwave and Noise Figure Measurements  

Microsoft Academic Search

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

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

1994-01-01

67

The cryogenic wind tunnel  

NASA Technical Reports Server (NTRS)

Based on theoretical studies and experience with a low speed cryogenic tunnel and with a 1/3-meter transonic cryogenic tunnel, the cryogenic wind tunnel concept was shown to offer many advantages with respect to the attainment of full scale Reynolds number at reasonable levels of dynamic pressure in a ground based facility. The unique modes of operation available in a pressurized cryogenic tunnel make possible for the first time the separation of Mach number, Reynolds number, and aeroelastic effects. By reducing the drive-power requirements to a level where a conventional fan drive system may be used, the cryogenic concept makes possible a tunnel with high productivity and run times sufficiently long to allow for all types of tests at reduced capital costs and, for equal amounts of testing, reduced total energy consumption in comparison with other tunnel concepts.

Kilgore, R. A.

1976-01-01

68

Cryogenic Fluid Management Facility  

NASA Technical Reports Server (NTRS)

The Cryogenic Fluid Management Facility (CFMF) is a reusable test bed which is designed to be carried into space in the Shuttle cargo bay to investigate systems and technologies required to efficiently and effectively manage cryogens in space. The facility hardware is configured to provide low-g verification of fluid and thermal models of cryogenic storage, transfer concepts and processes. Significant design data and criteria for future subcritical cryogenic storage and transfer systems will be obtained. Future applications include space-based and ground-based orbit transfer vehicles (OTV), space station life support, attitude control, power and fuel depot supply, resupply tankers, external tank (ET) propellant scavenging, space-based weapon systems and space-based orbit maneuvering vehicles (OMV). This paper describes the facility and discusses the cryogenic fluid management technology to be investigated. A brief discussion of the integration issues involved in loading and transporting liquid hydrogen within the Shuttle cargo bay is also included.

Eberhardt, R. N.; Bailey, W. J.; Symons, E. P.; Kroeger, E. W.

1984-01-01

69

Cryogenic hydrogen-induced air liquefaction technologies  

NASA Technical Reports Server (NTRS)

Extensively utilizing a special advanced airbreathing propulsion archives database, as well as direct contacts with individuals who were active in the field in previous years, a technical assessment of cryogenic hydrogen-induced air liquefaction, as a prospective onboard aerospace vehicle process, was performed and documented. The resulting assessment report is summarized. Technical findings are presented relating the status of air liquefaction technology, both as a singular technical area, and also that of a cluster of collateral technical areas including: compact lightweight cryogenic heat exchangers; heat exchanger atmospheric constituents fouling alleviation; para/ortho hydrogen shift conversion catalysts; hydrogen turbine expanders, cryogenic air compressors and liquid air pumps; hydrogen recycling using slush hydrogen as heat sink; liquid hydrogen/liquid air rocket-type combustion devices; air collection and enrichment systems (ACES); and technically related engine concepts.

Escher, William J. D.

1990-01-01

70

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

71

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

72

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.

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

2005-08-29

73

32GHz cryogenically cooled HEMT low-noise amplifiers  

Microsoft Academic Search

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

K. H. George Duh; William F. Kopp; Pin Ho; Pane-Chane Chao; Ming-Yih Ko; Phillip M. Smith; James M. Ballingall; J. Javier Bautista; Gerardo G. Ortiz

1989-01-01

74

On 32GHz cryogenically cooled HEMT low-noise amplifiers  

Microsoft Academic Search

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

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

1988-01-01

75

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

76

Cryogenic Insulation Systems  

NASA Technical Reports Server (NTRS)

The results of a comparative study of cryogenic insulation systems performed are presented. The key aspects of thermal insulation relative to cryogenic system design, testing, manufacturing, and maintenance are discussed. An overview of insulation development from an energy conservation perspective is given. Conventional insulation materials for cryogenic applications provide three levels of thermal conductivity. Actual thermal performance of standard multilayer insulation (MLI) is several times less than laboratory performance and often 10 times worse than ideal performance. The cost-effectiveness of the insulation system depends on thermal performance; flexibility and durability; ease of use in handling, installation, and maintenance; and overall cost including operations, maintenance, and life cycle. Results of comprehensive testing of both conventional and novel materials such as aerogel composites using cryostat boil-off methods are given. The development of efficient, robust cryogenic insulation systems that operate at a soft vacuum level is the primary focus of this paper.

Augustynowicz, S. D.; Fesmire, J. E.; Wikstrom, J. P.

1999-01-01

77

Cryogenic Expansion Machine.  

National Technical Information Service (NTIS)

A reciprocating expansion-engine refrigerator for cooling helium to a low temperature is described. The cryogenic expansion engine includes intake and exhaust poppet valves each controlled by a cam having adjustable dwell, the valve seats for the valves b...

C. B. Pallaver M. W. Morgan

1976-01-01

78

Cryogenics in BEPCII Upgrade.  

National Technical Information Service (NTIS)

This paper presents cryogenic design for upgrading the Beijing Electron-Positron Collider (BEPC) at the Institute of High Energy Physics (IHEP) in Beijing. The upgrade involves three new superconducting facilities, the interaction region quadrupole magnet...

L. Jia L. Wang S. Li

2002-01-01

79

Recent Subjects in Cryogenics  

NASA Astrophysics Data System (ADS)

Several topics in the field of cryogenic engineering are described. Those are cryopumping and small refrigerators, Squid and its applications, large superconducting equipments such as a magnet for nuclear fusion, a magnet for NMR-CT, and magnetic refrigerators.

Nagano, Hiroshi

80

Cryogenic Insulation System  

NASA Technical Reports Server (NTRS)

This invention relates to reusable, low density, high temperature cryogenic foam insulation systems and the process for their manufacture. A pacing technology for liquid hydrogen fueled, high speed aircraft is the development of a fully reusable, flight weight cryogenic insulation system for propellant tank structures. In the invention cryogenic foam insulation is adhesively bonded to the outer wall of the fuel tank structure. The cryogenic insulation consists of square sheets fabricated from an array of abutting square blocks. Each block consists of a sheet of glass cloth adhesively bonded between two layers of polymethacrylimide foam. Each block is wrapped in a vapor impermeable membrane, such as Kapton(R) aluminum Kapton(R), to provide a vapor barrier. Very beneficial results can be obtained by employing the present invention in conjunction with fibrous insulation and an outer aeroshell, a hot fuselage structure with an internal thermal protection system.

Davis, Randall C. (inventor); Taylor, Allan H. (inventor); Jackson, L. Robert (inventor); Mcauliffe, Patrick S. (inventor)

1988-01-01

81

Cryogenic Insulation Development.  

National Technical Information Service (NTIS)

Multilayer insulations for long term cryogenic storage are described. The devulted 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 ...

K. E. Leonhard

1972-01-01

82

Cryogenic Insulation System.  

National Technical Information Service (NTIS)

This invention relates to reusable, low density high temperature cryogenic foam insulation systems and the process for their manufactire. A pacing technology for liquid hydrogen fueled, high speed aircraft is the development of a fully-reusable, flight-we...

R. C. Davis A. H. Taylor L. R. Jackson P. S. McAuliffee

1987-01-01

83

Destratification of Cryogenic Propellants.  

National Technical Information Service (NTIS)

This document discusses destratification of cryogenic propellants. Various destratification systems are evaluated and compared. The axial and radial jet concepts are found to offer the best performance, simplicity, compactness and low system weight. The p...

J. B. Urquhart

1969-01-01

84

Vuilleumier Cycle Cryogenic Refrigeration.  

National Technical Information Service (NTIS)

This report describes in detailed the Vuilleumier (V-M) refrigeration cycle and various ways it has been applied to produce cryogenic temperatures. It starts with the most theoretical model of the Vuilleumier cycle and gradually adds complicating factors ...

R. White

1976-01-01

85

Oxygen Chemisorption Cryogenic Refrigerator.  

National Technical Information Service (NTIS)

The present invention relates to a chemisorption compressor cryogenic refrigerator which employs oxygen to provide cooling at 60 K to 100 K. The invention includes dual vessels containing an oxygen absorbent material, alternately heated and cooled to prov...

J. A. Jones

1986-01-01

86

APT Cryogenic System  

Microsoft Academic Search

In the Accelerator Production of Tritium (APT) project, a one-kilometer-long linear accelerator (linac) is used as part of a plant that will provide tritium for national defense purposes. The accelerator consists of a low-energy (LE) normally conductive, radiofrequency (rf) linac and a high-energy (HE) superconducting rf linac. The APT cryogenic system will supply cryogenic helium fluids to maintain the HE

G. J. Laughon; C. H. Rode; R. Ganni; W. C. Chronis; D. M. Arenius; B. S. Bevins

1999-01-01

87

Cryogenic Shutter Mechanism  

NASA Technical Reports Server (NTRS)

Electromagnetic shutter mechanism operates at ambient and cryogenic temperatures to shield optical element, such as mirror, filter, polarizer, beam splitter, or detector, from external light and radiation in cryogenic Dewar equipped with window for optical evaluation. Shutter mechanism in Dewar container alternately shields and exposes optical element as paddle rotates between mechanical stops. Mounted on cold plate of liquid-helium reservoir. Paddle, shaft, and magnet constitutes assembly rotated by electromagnetic field on coil.

Barney, Richard D.; Magner, Thomas J.

1989-01-01

88

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

89

Physical sciences: Thermodynamics, cryogenics, and vacuum technology: A compilation  

NASA Technical Reports Server (NTRS)

Technological developments which have potential application outside the aerospace community are reported. A variety of thermodynamic devices including heat pipes and cooling systems are described along with methods of handling cryogenic fluids. Vacuum devices are also described. Pata et information is included.

1974-01-01

90

Settled Cryogenic Propellant Transfer  

NASA Technical Reports Server (NTRS)

Cryogenic propellant transfer can significantly benefit NASA s space exploration initiative. LMSSC parametric studies indicate that "Topping off" the Earth Departure Stage (EDS) in LEO with approx.20 mT of additional propellant using cryogenic propellant transfer increases the lunar delivered payload by 5 mT. Filling the EDS to capacity in LEO with 78 mT of propellants increases the delivered payload by 20 mT. Cryogenic propellant transfer is directly extensible to Mars exploration in that it provides propellant for the Mars Earth Departure stage and in-situ propellant utilization at Mars. To enable the significant performance increase provided by cryogenic propellant transfer, the reliability and robustness of the transfer process must be guaranteed. By utilizing low vehicle acceleration during the cryogenic transfer the operation is significantly simplified and enables the maximum use of existing, reliable, mature upper stage cryogenic-fluid-management (CFM) techniques. Due to settling, large-scale propellant transfer becomes an engineering effort, and not the technology development endeavor required with zero-gravity propellant transfer. The following key CFM technologies are all currently implemented by settling on both the Centaur and Delta IV upper stages: propellant acquisition, hardware chilldown, pressure control, and mass gauging. The key remaining technology, autonomous rendezvous and docking, is already in use by the Russians, and must be perfected for NASA whether the use of propellant transfer is utilized or not.

Kutter, Bernard F.; Zegler, Frank; Sakla, Steve; Wall, John; Hopkins, Josh; Saks, Greg; Duffey, Jack; Chato, David J.

2006-01-01

91

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

92

Cryogenic capillary screen heat entrapment  

NASA Astrophysics Data System (ADS)

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 subcooled 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 liquid nitrogen (LN 2) 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, 200 × 1400 and 325 × 2300, both with Twill Dutch Weave. Upon consideration of both the water and LN 2 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.; Statham, G.

2008-05-01

93

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

94

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 microrefrigerating 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

2013-02-12

95

Study of Cryogenic Complex Plasma.  

National Technical Information Service (NTIS)

This Report describes the investigation entitled by 'Study of Cryogenic Complex Plasma.' The research has been carried out at Yokohama National University. Our overall goal is to study the cryogenic complex plasma experimentally and theoretically and to r...

C. Kijima M. Shindo O. Ishihara Y. Nakamura

2007-01-01

96

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

97

Cryogenic vacuum tight adhesive  

NASA Astrophysics Data System (ADS)

A synthetic adhesive for vacuum tight joints at cryogenic temperatures has been developed. It consists of three components, the main component being epoxy silicone organic resin. The joints made with the adhesive remain vacuum tight at liquid helium temperature, including superfluid helium. It was found possible to connect different materials with the adhesive (copper and stainless steel with each other, aluminum, aluminum alloys, fiberglass, etc.). The joints withstood thermal shock tests of ten repeated sharps cooling to liquid nitrogen temperature and heating in hot water. Using the adhesive a lot of different vacuum tight low temperature joints have been made. More than fifteen years of wide application of this adhesive in vacuum tight cryogenic joints proved its high reliability. Some designs of vacuum tight cryogenic joints are presented and the technique of their manufacturing is described.

Anashkin, O. P.; Keilin, V. E.; Patrikeev, V. M.

1999-12-01

98

CEBAF cryogenic system  

SciTech Connect

The CEBAF cryogenic system consists of 3 refrigeration systems: Cryogenic Test Facility (CTF), Central Helium Liquefier (CHL), and End Station Refrigerator (ESR). CHL is the main cryogenic system for CEBAF, consisting of a 4.8 kW, 2.0 K refrigerator and transfer line system to supply 2.0 K and 12 kW of 50 K shield refrigeration for the Linac cavity cryostats and 10 g/s of liquid for the end stations. This paper describes the 9-year effort to commission these systems, concentrating on CHL with the cold compressors. The cold compressors are a cold vacuum pump with an inlet temperature of 3 K which use magnetic bearings, thereby eliminating the possibility of air leaks into the subatmospheric He.

NONE

1995-12-31

99

Cryogenic applications for environment simulation.  

NASA Technical Reports Server (NTRS)

Some of the applications of cryogenics for simulating space environmental conditions are reviewed, and typical existing space simulation facilities are described. The techniques of adapting cryogenics to environmental simulation are discussed. Special attention is given to cryosorption pumps designed to accelerate cryogenic cooling of the adsorbent material.

Hardgrove, W. F.

1972-01-01

100

Dielectric Properties of Cryogenic Liquids  

Microsoft Academic Search

Electric-breakdown measurements at 60 Hz have been made with cryogenic liquids-nitrogen, hydrogen, and helium. All of the cryogenic liquids have higher breakdown voltages than conventional transformer oil, except liquid helium which breaks down at a considerably lower voltage. The measured values of dielectric constant for the cryogenic liquids agree quite well with the published literature. The dissipation factor of the

KCENNETH N. MATHES

1967-01-01

101

Cryogen spray cooling in laser dermatology: Effects of ambient humidity and frost formation  

Microsoft Academic Search

Background and Objective: Dynamics of cryogen spray deposition, water condensation and frost formation is studied in relationship to cooling rate and efficiency of cryogen spray cooling (CSC) in combination with laser dermatologic surgery. Study Design\\/Materials and Methods: A high-speed video camera was used to image the surface of human skin during and after CSC using a commercial device. The influence

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

2001-01-01

102

Cryogen acquisition in orbit  

NASA Technical Reports Server (NTRS)

Orbital cryogen acquisition is a definite requirement for engine restart and/or propellant transfer on all major future missions. The most promising methods, especially for large scale vehicles, are acquisition by linear acceleration and acquisition by capillary systems. Intermittent acceleration and propellant settling requires some state-of-the-art extension since it has not been attempted on a large scale cryogen vehicle. Capillary acquisition systems offer the advantages of reusability, passiveness, low weight, and mission flexibility. The major disadvantage is that of an undeveloped technology. The method does not lend itself to verification through ground testing.

Hastings, L. J.

1971-01-01

103

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

104

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

105

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

106

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

107

Cryogenic fluid dynamics  

Microsoft Academic Search

Ultrahigh Reynolds (Re) and Rayleigh (Ra) number flow can be produced and studied under controlled laboratory conditions using cryogenic liquid and gaseous He. Recent results on Rayleigh–Benard convection, pipe flow and towed grid turbulence are discussed together with some aspects of the future development.

L. Skrbek; J. J. Niemela; R. J Donnelly

2000-01-01

108

Cryogenic Grating Spectrometer.  

National Technical Information Service (NTIS)

The Cryogenic Grating Spectrometer (CGS) first flew on the KAO in 1982 December and has been open to guest investigators since 1984 October. In the past 12 years it has completed over 100 research flights supporting 13 different principal investigators st...

E. F. Erickson, M. R. Haas, S. W. J. Colgan, J. P. Simpson, R. H. Rubin

1995-01-01

109

Oxygen chemisorption cryogenic refrigerator  

Microsoft Academic Search

The present invention relates to a chemisorption compressor cryogenic refrigerator which employs oxygen to provide cooling at 60 to 100 K. The invention includes dual vessels containing an oxygen absorbent material, alternately heated and cooled to provide a continuous flow of high pressure oxygen, multiple heat exchangers for precooling the oxygen, a Joule-Thomson expansion valve system for expanding the oxygen

Jack A. Jones

1987-01-01

110

Compact cryogenic inductors  

SciTech Connect

Power systems requiring power levels as high as a few megawatts to a few gigawatts for periods of several microseconds to several milliseconds with repetitive frequencies of a few hertz to a few kilohertz are being considered for potential space applications. The impulsive nature of the power presents the opportunity to use inductive energy storage techniques for pulse duty to enhance economic and practical considerations. An inductors must be efficient, lightweight, and reliable, and it must have high energy density if it is to be used in space based power systems. Cryogenic inductors are best studied for such an application. Parametric analyses of the two potential types of cryogenic inductors (superconducting and hyperconducting reveal that the hyperconducting (high purity aluminum)) inductor would be significantly lighter and achieve higher energy densities without the added penalty of a helium refrigeration system, thus resulting in improved overall system reliability. The lightweight hyperconducting cryogenic inductor technology is, however, in its infancy. This paper describes the required technology base which would allow the eventual application of the lightweight cryogenic inductor in space power systems, and also conclusively demonstrates the underlying principles.

Singh, S.K.; Carr, W.J. Jr.; Fagan, T.J. Jr.; Hordubay, T.D.; Chuboy, H.L. (Westinghouse Electric Corp., Pittsburgh, PA (United States). Science and Technology Center)

1994-07-01

111

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

112

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

Microsoft Academic Search

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

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

1994-01-01

113

Aging characteristics of cryogenic insulator for development of HTS transformer  

Microsoft Academic Search

In the response to the demand for electrical energy, much effort aimed to develop and commercialize high temperature superconducting (HTS) power equipments has been made around the world. Especially, HTS transformer is one of the most promising devices. For the development of HTS transformer, the cryogenic insulation technology should be established. In this paper V?t characteristics of polyimide (Kapton) tape

Van-Dung Nguyen; Jong-Man Joung; Seung-Myeong Baek; Chang-Hwa Lee; Sang-Hyun Kim

2005-01-01

114

Refrigeration and Cryogenics Specialist. J3ABR54530  

ERIC Educational Resources Information Center

This document package contains an Air Force course used to train refrigeration and cryogenics specialists. The course is organized in six blocks designed for group instruction. The blocks cover the following topics: electrical principles; fundamentals of tubing and piping; metering devices, motor controls, domestic and commercial refrigeration;…

Air Force Training Command, Sheppard AFB, TX.

115

Noise parameter measurement of microwave transistors at cryogenic temperature  

Microsoft Academic Search

A major drawback of active two-port microwave noise parameter measurement, by means of the multiple impedance technique at cryogenic temperature, lies in that a nonnegligible part of a lossy transmission line featuring a nonuniform temperature must be inserted between the automatic tuner (operated at room temperature) and the device input. Since the temperature distribution over that line is not precisely

Laurent Escotte; F. Sejalon; J. Graffeuil

1994-01-01

116

Cryogenic mirror analysis  

NASA Technical Reports Server (NTRS)

Due to extraordinary distances scanned by modern telescopes, optical surfaces in such telescopes must be manufactured to unimaginable standards of perfection of a few thousandths of a centimeter. The detection of imperfections of less than 1/20 of a wavelength of light, for application in the building of the mirror for the Space Infrared Telescope Facility, was undertaken. Because the mirror must be kept very cold while in space, another factor comes into effect: cryogenics. The process to test a specific morror under cryogenic conditions is described; including the follow-up analysis accomplished through computer work. To better illustrate the process and analysis, a Pyrex Hex-Core mirror is followed through the process from the laser interferometry in the lab, to computer analysis via a computer program called FRINGE. This analysis via FRINGE is detailed.

Nagy, S.

1988-01-01

117

Flexible cryogenic conduit  

DOEpatents

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, Paul Daniel (Yorktown, VA); Wines, Robin Renee (Norfolk, VA); Takacs, James Joseph (Hayes, VA)

1999-01-01

118

Cryogenic thermal diodes  

NASA Astrophysics Data System (ADS)

Space based cryogenic thermal management systems for advanced infrared sensor platforms are a critical failure mode to the spacecraft missions they are supporting. Recent advances in cryocooler technologies have increased the achievable cooling capacities and decreased the operating temperatures of these systems, but there is still a fundamental need for redundancy in these systems. Cryogenic thermal diodes act as thermal switches, allowing heat to flow through them when in a conduction mode and restricting the flow of heat when in an isolation mode. These diodes will allow multiple cryocoolers to cool a single infrared focal plane array. The Space Dynamics Laboratory has undertaken an internal research and development effort to develop this innovative technology. This paper briefly describes the design parameters of several prototype thermal diodes that were developed and tested. .

Paulsen, Brandon R.; Batty, J. C.; Agren, John

2000-01-01

119

Cryogenic treatment of gas  

SciTech Connect

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

120

Oxygen chemisorption cryogenic refrigerator  

NASA Astrophysics Data System (ADS)

The present invention relates to a chemisorption compressor cryogenic refrigerator which employs oxygen to provide cooling at 60 to 100 K. The invention includes dual vessels containing an oxygen absorbent material, alternately heated and cooled to provide a continuous flow of high pressure oxygen, multiple heat exchangers for precooling the oxygen, a Joule-Thomson expansion valve system for expanding the oxygen to partially liquefy it and a liquid oxygen pressure vessel. The primary novelty is that, while it was believed that once oxygen combined with an element or compound the reaction could not reverse to release gaseous oxygen, in this case oxygen will indeed react in a reversible fashion with certain materials and will do so at temperatures and pressures which make it practical for incorporation into a cryogenic refrigeration system.

Jones, Jack A.

1987-10-01

121

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

122

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

123

Cryogenic electronic memory infrastructure for physically related “continuity of care records” of frozen cells  

NASA Astrophysics Data System (ADS)

This paper describes low-temperature electronics for cryogenic applications, especially for a new technique for living-cell storage near liquid-nitrogen temperatures. Central is the reliable coupling of a sample carrier to cryo-tolerant electronics, particularly memory devices storing continuity of care records, lab workflows, and other useful documentation. We present (1) a two-year study of the performance and data retention of Flash-Memory devices in a controlled cryogenic environment, (2) a cryogenic multiplexer allowing multiple, cold Flash-Memories to share a communication channel, and (3) results for radio frequency identification tags immersed in liquid nitrogen.

Ihmig, Frank R.; Shirley, Stephen G.; Durst, Christopher H. P.; Zimmermann, Heiko

2006-04-01

124

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

125

The Cryogenic Grating Spectrometer  

NASA Technical Reports Server (NTRS)

The Cryogenic Grating Spectrometer (CGS) first flew on the KAO in 1982 December and has been open to guest investigators since 1984 October. In the past 12 years it has completed over 100 research flights supporting 13 different principal investigators studying a variety of objects. We briefly describe the instrument, its capabilities and accomplishments, and acknowledge the people who have contributed to its development and operation.

Erickson, Edwin F.; Haas, Michael R.; Colgan, Sean W. J.; Simpson, Janet P.; Rubin, Robert H.

1995-01-01

126

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

127

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 to react against the tension and bending of the primary liner caused by thermal stresses. The primary membrane

McCown

1978-01-01

128

Cryogenic support member  

DOEpatents

A cryogenic support member is comprised of a nonmetallic 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, R.C.; Gonczy, J.D.; Nicol, T.H.

1986-05-15

129

Cryogenic Treatment of Metal Parts  

NASA Astrophysics Data System (ADS)

Cryogenic treatment and its variables have been described. Results of eight engineering tests carried out on cryotreated parts have been presented. Cryogenic treatment of metal parts enhances useful properties which in turn, improves various strengths. Our tests viz. Abrasion, Torsion, Fatigue, Tensile, Shear, Hardness and Impact on Mild steel, Cast Iron, Brass and Copper show that the cryogenic treatment improved useful properties of mild steel parts appreciably but did not show promise with brass and copper parts.

Chillar, Rahul; Agrawal, S. C.

2006-03-01

130

Cryogenic Treatment of Metal Parts  

SciTech Connect

Cryogenic treatment and its variables have been described. Results of eight engineering tests carried out on cryotreated parts have been presented. Cryogenic treatment of metal parts enhances useful properties which in turn, improves various strengths. Our tests viz. Abrasion, Torsion, Fatigue, Tensile, Shear, Hardness and Impact on Mild steel, Cast Iron, Brass and Copper show that the cryogenic treatment improved useful properties of mild steel parts appreciably but did not show promise with brass and copper parts.

Chillar, Rahul [S. P. College of Engineering, Andheri (W), Mumbai - 400 058 (India); Agrawal, S. C. [Tata Institute of Fundamental Research, Colaba, Mumbai - 400 005 (India)

2006-03-31

131

Cryogenic Flow Research Facility Provisional Accuracy Statement.  

National Technical Information Service (NTIS)

The National Bureau of Standards and the Compressed Gas Association have jointly sponsored a research program on cryogenic flow measurement. A cryogenic flow research facility was constructed and was first used to evaluate commercially available cryogenic...

J. W. Dean J. A. Brennan D. B. Mann C. H. Kneebone

1971-01-01

132

Reference Guide for Cryogenic Properties of Materials.  

National Technical Information Service (NTIS)

A thorough knowledge of the behavior of materials at cryogenic temperatures is critical for the design of successful cryogenic systems. Over the past 50 years, a tremendous amount of material properties at cryogenic temperatures have been measured and pub...

J. G. Weisend F. E. Thompson

2003-01-01

133

Material Damping Experiments at Cryogenic Temperatures  

NASA Technical Reports Server (NTRS)

A unique experimental facility has been designed to measure damping of materials at cryogenic temperatures. The test facility pays special attention to removing 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 is obtained for materials (AI, GrEp, Be, Fused Quartz), strain amplitudes (less than 10-6 ppm), frequencies (20Hz-330Hz) and temperatures (20K-293K) relevant to future precision optical space missions. The test data shows a significant decrease in viscous damping at cryogenic temperatures and can be as low as 10-4%, but the amount of the damping decrease is a function of frequency and material. Contrary to the other materials whose damping monotonically decreased with temperature, damping of Fused Quartz increased substantially at cryo, after reaching a minimum at around l50 K. The damping is also shown to be insensitive to strain for low strain levels. At room temperatures, the test data correlates well to the analytical predictions of the Zener damping model. Discrepancies at cryogenic temperatures between the model predictions and the test data are observed.

Levine, Marie; White, Christopher

2003-01-01

134

Precision Cryogenic Dilatometer  

NASA Technical Reports Server (NTRS)

A dilatometer based on a laser interferometer is being developed to measure mechanical creep and coefficients of thermal expansion (CTEs) of materials at temperatures ranging from ambient down to 15 K. This cryogenic dilatometer has been designed to minimize systematic errors that limit the best previously available dilatometers. At its prototype stage of development, this cryogenic dilatometer yields a strain measurement error of 35 ppb or 1.7 ppb/K CTE measurement error for a 20-K thermal load, for low-expansion materials in the temperature range from 310 down to 30 K. Planned further design refinements that include a provision for stabilization of the laser and addition of a high-precision sample-holding jig are expected to reduce the measurement error to 5-ppb strain error or 0.3-ppb/K CTE error for a 20-K thermal load. The dilatometer (see figure) includes a common-path, differential, heterodyne interferometer; a dual-frequency, stabilized source bench that serves as the light source for the interferometer; a cryogenic chamber in which one places the material sample to be studied; a cryogenic system for cooling the interior of the chamber to the measurement temperature; an ultra-stable alignment stage for positioning the chamber so that the sample is properly positioned with respect to the interferometer; and a data-acquisition and control system. The cryogenic chamber and the interferometer portion of the dilatometer are housed in a vacuum chamber on top of a vibration isolating optical table in a cleanroom. The sample consists of two pieces a pillar on a base both made of the same material. Using reflections of the interferometer beams from the base and the top of the pillar, what is measured is the change in length of the pillar as the temperature in the chamber is changed. In their fundamental optical and electronic principles of operation, the laser light source and the interferometer are similar to those described in Common-Path Heterodyne Interferometers (NPO-20786), NASA Tech Briefs, Vol. 25, No. 7 (July 2001), page 12a, and Interferometer for Measuring Displacement to Within 20 pm (NPO- 21221), NASA Tech Briefs, Vol. 27, No. 7 (July 2003), page 8a. However, the present designs incorporate a number of special geometric, optical, and mechanical features to minimize optical and thermal-expansion effects that contribute to measurement errors. These features include the use of low-thermal expansion materials for structural components, kinematic mounting and symmetrical placement of optical components, and several measures taken to minimize spurious reflections of laser beams.

Dudik, Matthew; Halverson, Peter; Levine-West, Marie; Marcin, Martin; Peters, Robert D.; Shaklan, Stuart

2005-01-01

135

International Cryogenic Engineering Conference, 13th, Beijing, People's Republic of China, Apr. 24-27, 1990, Proceedings  

Microsoft Academic Search

The present conference on state-of-the-art cryogenics devices and their applications discusses multi-SQUID magnetometers for neuromagnetic research, cryogenics in the Chinese space program, LH2-fueled automobiles, the application on nonmetallic composites to cryogenic systems, refrigeration equipment, He-gas purification, cooling for superconducting systems, cryocooler regenerator materials, Stirling refrigerators, pulse-tube refrigerators, and Gifford-McMahon and Vuilleumier refrigerators. Also treated are the heat-transfer and flow resistance

C. S. Hong

1990-01-01

136

Experimental cryogenic modeling and noise of SiGe HBTs  

Microsoft Academic Search

SiGe devices are an exciting contender for extremely low noise, cryogenically cooled amplifiers. This paper begins with a procedure for extracting a simple equivalent circuit model capable of accurately describing SiGe HBT devices. Next, small-signal modeling results obtained for a 3times0.12times18um2 SiGe HBT at 15, 40, 77, 120, 200, and 300 K are presented along with discussion of performance enhancements

Joseph C. Bardin; Sander Weinreb

2008-01-01

137

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

138

Electromechanical Materials for Cryogenic Use  

NASA Technical Reports Server (NTRS)

Electromechanical materials can be used in smart sensor and actuator devices. Yet none performing at low temperatures are available. To meet this need, Pb((MgNi)(1/3)Ta(2/3))03 was synthesized as an electrostrictive ceramic for applications in cryogenic environments. Employing the columbite precursor route, samples with 0% to 100% Ni substitution for Mg were prepared, but only samples with Ni-substitutions less than or equal to 20% yielded primarily the desired perovskite phase. For these compositions the temperature of highest permittivity decreased linearly with increasing Ni content to yield a minimum value of -124 C for 20% Ni-substitution. This composition showed good relaxor dielectric behavior with a maximum relative permittivity of 5890 at 1 kHz. Additionally, in samples with excess MgO, the magnitude of permittivity doubled. In this effort, Pb((MgNi)(1/3)Ta(2/3))03 (PMNiTa) was fabricated to lower its transition temperature by substituting Ni for Mg successively.

Leidinger, Peter; Pilgrim, Steven M.

1996-01-01

139

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

140

Cryogenic fluid transfer for exploration  

Microsoft Academic Search

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

David J. Chato

2008-01-01

141

Vibration dampers for cryogenic turbomachinery  

NASA Technical Reports Server (NTRS)

This paper describes the development of effective and reliable minimum-weight and minimum-envelope vibration dampers for cryogenic turbines. To meet this objective, a high speed test rig was designed and fabricated, which is currently used to test a curved beam type damper. The operation, capacity, structural characteristics, measurement system, and safety features of the cryogenic damper test rig are discussed.

Palazzolo, Alan B.; Olan, Emmanuel; Ibrahim, Azman Syed; Kascak, Albert F.

1990-01-01

142

Cryogenic foam insulation: abstracted publications  

Microsoft Academic Search

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

1977-01-01

143

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

144

Kodak AMSD Cryogenic Test Plans  

NASA Technical Reports Server (NTRS)

NGST will be an IR based optical system that will operate at cryogenic temperatures. As part of the AMSD program, Kodak must demonstrate the ability of our system to perform at these very cold temperatures. Kodak will discuss the test approach that will be used for cryogenic testing at MSFC's XRCF.

Matthews, Gary; Hammon, John; Barrett, David; Russell, Kevin (Technical Monitor)

2002-01-01

145

Magnetic bearings for cryogenic turbomachines  

Microsoft Academic Search

Magnetic bearings offer a number of advantages over gas bearings for the support of rotors in cryogenic turboexpanders and compressors. Their performance is relatively independent of the temperature or pressure of the process gas for a large range of conditions. Active magnetic bearing systems that use capacitive sensors have been developed for high speed compressors for use in cryogenic refrigerators.

Victor Iannello; Herbert Sixsmith

1991-01-01

146

Study of Cryogenic Complex Plasma.  

National Technical Information Service (NTIS)

Overall goal is to study basic physics of a complex plasma at a room temperature as well as in a cryogenic environment and to reveal novel natures of a cryogenic complex plasma produced by a stable discharge above or in super fluid liquid helium . This fi...

O. Ishihara

2008-01-01

147

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

148

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

149

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

150

FRIB cryogenic distribution system  

SciTech Connect

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, Venkatarao [JLAB; Dixon, Kelly D. [JLAB; Laverdure, Nathaniel A. [JLAB; Knudsen, Peter N. [JLAB; Arenius, Dana M. [JLAB; Barrios, Matthew N. [Michigan State; Jones, S. [Michigan State; Johnson, M. [Michigan State; Casagrande, Fabio [Michigan State

2014-01-01

151

Cryogenic Propellant Scavenging  

NASA Technical Reports Server (NTRS)

A detailed description of a computer model that has been developed for assessing the feasibility of low g cryogen propellant scavenging from the space shuttle External Tank (ET) is given. Either pump-assisted or pressure-induced propellant transfer may be selected. The program will accept a wide range of input variables, including the fuel to be transferred (LOX or LH2), heat leaks, tank temperatures, and piping and equipment specifications. The model has been parametrically analyzed to determine initial design specification for the system.

Louie, B.; Kemp, N. J.; Daney, D. E.

1985-01-01

152

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

153

Cryogenic distribution for the Facility for Rare Isotope Beams  

SciTech Connect

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.

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

2012-06-01

154

CONE - An STS-based cryogenic fluid management experiment  

NASA Technical Reports Server (NTRS)

An overview of the CONE program is presented which includes a definition of the technology addressed by CONE and a baseline experiment set, a description of the experimental and support subsystems, interface requirements between the STS and the experiment carrier (Hitchhiker M), and the reusability and expansion capacity for additional experiment flights. CONE evaluates three primary technologies: the active thermodynamic vent system, the passive thermodynamic vent system, and liquid acquisition device performance. The cryogenic fluid management technology database that the system offers will allow for efficient subcritical cryogenic system designs for operation in a low-gravity environment. This system maximizes the balance between existing component technology and the need for the development of a cryogenic-fluid-management (CFM) test bed to investigate and demonstrate methods of storage and handling arenas.

Bell, R. S.; Vento, D. M.; Hanna, G. J.

1992-01-01

155

Cryogenic hydrogen-induced air-liquefaction technologies  

NASA Technical Reports Server (NTRS)

Extensive use of a special advanced airbreathing propulsion archives data base, as well as direct contacts with individuals who were active in the field in previous years, a technical assessment of cryogenic hydrogen induced air liquefaction, as a prospective onboard aerospace vehicle process, was performed and documented in 1986. The resulting assessment report is summarized. Technical findings relating the status of air liquefaction technology are presented both as a singular technical area, and also as that of a cluster of collateral technical areas including: Compact lightweight cryogenic heat exchangers; Heat exchanger atmospheric constituents fouling alleviation; Para/ortho hydrogen shift conversion catalysts; Hydrogen turbine expanders, cryogenic air compressors and liquid air pumps; Hydrogen recycling using slush hydrogen as heat sinks; Liquid hydrogen/liquid air rocket type combustion devices; Air Collection and Enrichment System (ACES); and Technically related engine concepts.

Escher, William J. D.

1990-01-01

156

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

157

Cryogenics maintenance strategy  

NASA Astrophysics Data System (ADS)

ALMA is an interferometer composed of 66 independent systems, with specific maintenance requirements for each subsystem. To optimize the observation time and reduce downtime maintenance, requirements are very demanding. One subsystem with high maintenance efforts is cryogenics and vacuum. To organize the maintenance, the Cryogenic and Vacuum department is using and implementing different tools. These are monitoring and problem reporting systems and CMMS. This leads to different maintenance approaches: Preventive Maintenance, Corrective Maintenance and Condition Based Maintenance. In order to coordinate activities with other departments the preventive maintenance schedule is kept as flexible as systems allow. To cope with unavoidable failures, the team has to be prepared to work under any condition with the spares on time. Computerized maintenance management system (CMMS) will help to manage inventory control for reliable spare part handling, the correct record of work orders and traceability of maintenance activities. For an optimized approach the department is currently evaluating where preventive or condition based maintenance applies to comply with the individual system demand. Considering the change from maintenance contracts to in-house maintenance will help to minimize costs and increase availability of parts. Due to increased number of system and tasks the cryo team needs to grow. Training of all staff members is mandatory, in depth knowledge must be built up by doing complex maintenance activities in the Cryo group, use of advanced computerized metrology systems.

Cruzat, Fabiola

2012-09-01

158

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

159

Cryogenic properties, processes and applications - 1986  

Microsoft Academic Search

This book presents the papers given at a conference on cryogenics. Topics considered at the conference included cryogenic refrigeration cycles and cycle analysis, compressors, thermodynamics, cryogenic heat transfer, convection, thermal insulation, safety, reliability, cryogenic applications, superconductor super collider, moderators, space vehicles, cryostats, superconducting magnets, and the design of tube-in-shell heat exchangers.

A. J. Kidnay; M. J. Hiza

1986-01-01

160

Cryogenic gas purification process and apparatus  

Microsoft Academic Search

This patent describes a process for the ultrapurification of cryogenic low boiling liquified gases containing trace impurities. It comprises: introducing the cryogenic gas to be purified into a first distillation column, the cryogenic gas to be purified being substantially at its liquid-gas equilibrium temperature at the pressures within the first distillation column; separating the cryogenic feed by distillation into a

Eyre

1989-01-01

161

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

162

International Cryogenic Engineering Conference, 13th, Beijing, People's Republic of China, Apr. 24-27, 1990, Proceedings  

NASA Astrophysics Data System (ADS)

The present conference on state-of-the-art cryogenics devices and their applications discusses multi-SQUID magnetometers for neuromagnetic research, cryogenics in the Chinese space program, LH2-fueled automobiles, the application on nonmetallic composites to cryogenic systems, refrigeration equipment, He-gas purification, cooling for superconducting systems, cryocooler regenerator materials, Stirling refrigerators, pulse-tube refrigerators, and Gifford-McMahon and Vuilleumier refrigerators. Also treated are the heat-transfer and flow resistance characteristics of narrow channels and porous materials, perforated-plate and wire-mesh heat exchangers, cryogenic insulation, He II research, cryogenic thermometry, space cryogenics, experimental cryostats and refrigerators, cryobiological developments, superconducting magnet technologies and power supplies, superconductor materials and their applications, high T(c) superconductors and their thin-film fabrication, and SQUIDs and their applications.

Hong, C. S.

1990-09-01

163

Ultrastable Cryogenic Microwave Oscillators  

NASA Astrophysics Data System (ADS)

Ultrastable cryogenic microwave oscillators are secondary frequency standards in the microwave domain. The best of these oscillators have demonstrated a short term frequency stability in the range 10-14 to a few times 10-16. The main application for these oscillators is as flywheel oscillators for the next generation of passive atomic frequency standards, and as local oscillators in space telemetry ground stations to clean up the transmitter close in phase noise. Fractional frequency stabilities of passive atomic frequency standards are now approaching 3 x10^-14 /? where ? is the measurement time, limited only by the number of atoms that are being interrogated. This requires an interrogation oscillator whose short-term stability is of the order of 10-14 or better, which cannot be provided by present-day quartz technology. Ultrastable cryogenic microwave oscillators are based on resonators which have very high electrical Q-factors. The resolution of the resonator's linewidth is typically limited by electronics noise to about 1ppm and hence Q-factors in excess of 108 are required. As these are only attained in superconducting cavities or sapphire resonators at low temperatures, use of liquid helium cooling is mandatory, which has so far restricted these oscillators to the research or metrology laboratory. Recently, there has been an effort to dispense with the need for liquid helium and make compact flywheel oscillators for the new generation of primary frequency standards. Work is under way to achieve this goal in space-borne and mobile liquid-nitrogen-cooled systems. The best cryogenic oscillators developed to date are the ``whispering gallery'' (WG) mode sapphire resonator-oscillators of NASA's Jet Propulsion Laboratory (JPL) and the University of Western Australia (UWA), as well as Stanford University's superconducting cavity stabilized oscillator (SCSO). All of these oscillators have demonstrated frequency stabilities in the range of a few times 10-15 to a few times 10-16. In this contribution we review only liquid-helium-cooled secondary frequency standards, such as those just mentioned, which have attained frequency stabilities of 10-14 or better.

Mann, Anthony G.

164

Cryogenic Two-Phase Flight Experiment: Results overview  

NASA Astrophysics Data System (ADS)

This paper focuses on the flight results of the Cryogenic Two-Phase Flight Experiment (CRYOTP), which was a Hitchhiker based experiment that flew on the space shuttle Columbia in March of 1994 (STS-62). CRYOTP tested two new technologies for advanced cryogenic thermal control; the Space Heat Pipe (SHP), which was a constant conductance cryogenic heat pipe, and the Brilliant Eyes Thermal Storage Unit (BETSU), which was a cryogenic phase-change thermal storage device. These two devices were tested independently during the mission. Analysis of the flight data indicated that the SHP was unable to start in either of two attempts, for reasons related to the fluid charge, parasitic heat leaks, and cryocooler capacity. The BETSU test article was successfully operated with more than 250 hours of on-orbit testing including several cooldown cycles and 56 freeze/thaw cycles. Some degradation was observed with the five tactical cryocoolers used as thermal sinks, and one of the cryocoolers failed completely after 331 hours of operation. Post-flight analysis indicated that this problem was most likely due to failure of an electrical controller internal to the unit.

Swanson, T.; Buchko, M.; Brennan, P.; Bello, M.; Stoyanof, M.

1995-09-01

165

LUX Cryogenics and Circulation  

NASA Astrophysics Data System (ADS)

LUX is a new dark matter direct detection experiment being carried out at the Sanford Underground Research Facility, at the renewed Homestake mine in Lead, SD. The detector's large size supports effective internal shielding from natural radioactivity of the surrounding materials and environment. The LUX detector consists of a cylindrical vessel containing 350 kg of liquid xenon (LXe) cooled down and maintained at 175-K operating temperature using a novel cryogenic system. We report the efficiency of our thermosyphon-based cooling system, as well as the efficiency of a unique internal heat exchanger with standard gas phase purification using a heated getter, which allows for very high flow purification without requiring large cooling power. Such systems are required for multi-ton scale up.

Bradley, Adam

2012-10-01

166

Basic cryogenics and materials  

NASA Technical Reports Server (NTRS)

The effects of cryogenic temperatures on the mechanical and physical properties of materials are summarized. Heat capacity and thermal conductivity are considered in the context of conservation of liquid nitrogen, thermal stability of the gas stream, and the response time for changes in operating temperature. Particular attention is given to the effects of differential expansion and failure due to thermal fatigue. Factors affecting safety are discussed, including hazards created due to the inadvertent production of liquid oxygen and the physiological effects of exposure to liquid and gaseous nitrogen, such as cold burns and asphyxiation. The preference for using f.c.c. metals at low temperatures is explained in terms of their superior toughness. The limitations on the use of ferritic steels is also considered. Nonmetallic materials are discussed, mainly in the context of their LOX compatibility and their use in the form of foams and fibers as insulatants, seals, and fiber reinforced composites.

Wigley, D. A.

1985-01-01

167

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

168

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

169

Cryogenic quartz crystal microbalance  

NASA Technical Reports Server (NTRS)

A radiatively cooled Cryogenic Quartz Crystal Microbalance designed to monitor highly volatile contaminants on the shuttle is described. Measurements are made with two 15-MHz microbalances having removable, optically polished sensors mounted in a radiant cooler. One sensor operates below the freezing point of water and monitors contamination including that of water vapor. The second sensor is heated and monitors the contamination background. It provides a reference from which the density of the water vapor cloud enveloping the shuttle is determined. The design incorporates a low-power dissipation oscillator, heaters for ice removal, and a method for attaching second-surface mirrors to the radiator employing an indium type solder instead of a room temperature vulcanizer.

Mckeown, D.; Sonnenschein, G.; Fox, M. G.

1975-01-01

170

Cryogenics and Einstein Telescope  

NASA Astrophysics Data System (ADS)

The dominant noises which limit the present sensitivity of the gravitational wave detectors are the thermal noise of the suspended mirrors and the shot noise. For the third generation of gravitational wave detectors as the Einstein Telescope (ET), the reduction of the shot noise implies to increase the power stored in the detector at 1 MW level and, at the same time, to compensate the huge optic distortion due to induced thermal lensing. At low temperature it is possible to reduce both these effects. However, lowering the temperature of the test masses without injecting vibration noise from the cooling system is a technological challenge. We review here the thermal noise impact on the ultimate ET sensitivity limit and we discuss possible cryogenic configurations to cool the mirror.

Puppo, Paola; Ricci, Fulvio

2011-02-01

171

Nanodielectrics for Cryogenic Applications  

SciTech Connect

In this paper we report the recent advances in nanodielectrics that were developed and tested for cryogenic dielectric applications. The systems studied are composed of nanometer size particles. Particles were produced using either an ex-situ or in-situ technique. It is observed that there are clear differences in the structural properties of materials produced using these two approaches. Either no significant degradation or improvement in the electrical insulation properties were observed for ex-situ nano-particle samples processed with an ultrasonic processor and in-situ nano-particle samples. Nanodielectrics have the potential to be tailored with better thermal and mechanical properties without losing their electrical insulation characteristics.

Tuncer, Enis [ORNL; Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Pace, Marshall O [ORNL; More, Karren [Oak Ridge National Laboratory (ORNL); Sathyamurthy, Srivatsan [University of Tennessee, Knoxville (UTK); Woodward, Jonathan [ORNL; Rondinone, Adam Justin [ORNL

2009-01-01

172

Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

The CPS is an in-space cryogenic propulsive stage based largely on state of the practice design for launch vehicle upper stages. However, unlike conventional propulsive stages, it also contains power generation and thermal control systems to limit the loss of liquid hydrogen and oxygen due to boil-off during extended in-space storage. The CPS provides the necessary (Delta)V for rapid transfer of in-space elements to their destinations or staging points (i.e., E-M L1). The CPS is designed around a block upgrade strategy to provide maximum mission/architecture flexibility. Block 1 CPS: Short duration flight times (hours), passive cryo fluid management. Block 2 CPS: Long duration flight times (days/weeks/months), active and passive cryo fluid management.

Jones, David

2011-01-01

173

Calculation Procedure, Optimization and Cost Factors of Normal-Conductive, Cryogenic and Superconducting Magnets for Experimental Plasma Physics.  

National Technical Information Service (NTIS)

A number of calculations and optimizing methods are presented for normally conductive, cryogenic, and superconducting magnets in linear (cylindrical) and toroidal devices. Relevant cost factors and functions are given as a basis for the comparison of cost...

B. Oswald

1972-01-01

174

Cryogenic moderator simulations : confronting reality.  

National Technical Information Service (NTIS)

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 r...

E. Iverson

1999-01-01

175

Adhesive for cryogenic temperature applications  

NASA Technical Reports Server (NTRS)

Adhesive, which bonds a metal liner to a filament wound composite structure used for cryogenic pressure vessels, prevents the metal liner from buckling under depressurization. The adhesive consists of adducts of urethane and epoxy resins.

Doyle, H. M.

1969-01-01

176

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

177

Cryogenic Refrigerators - An Updated Survey.  

National Technical Information Service (NTIS)

In 1969, we gave efficiency, weight, volume, and cost data for 95 cryogenic refrigerators and liquefiers excluding air separation plants. Recently, the survey was repeated. The original data and those for 49 additional refrigerators and liquefiers are pre...

T. R. Strobridge

1974-01-01

178

Ames Research Center Cryogenics Program.  

National Technical Information Service (NTIS)

Viewgraphs describe the Ames Research Center's cryogenics program. Diagrams are given of a fluid management system, a centrifugal pump, a flow meter, a liquid helium test facility, an extra-vehicular activity coupler concept, a dewar support with passive ...

P. Kittel

1987-01-01

179

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

180

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

181

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

182

Cryogenic refrigeration. (Latest citations from the NTIS Bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the development and applications of cryogenic refrigeration technology. Citations discuss performance evaluations of specific systems, equipment descriptions, the cooling of instrumentation, superconducting devices, reactor devices, and applications in satellites and spaceborne vehicles. (Contains 250 citations and includes a subject term index and title list.)

NONE

1993-12-01

183

Cryogenic refrigeration. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the development and applications of cryogenic refrigeration technology. Citations discuss performance evaluations of specific systems, equipment descriptions, the cooling of instrumentation, superconducting devices, reactor devices, and applications in satellites and spaceborne vehicles. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1994-12-01

184

Cryogenic refrigeration. (Latest citations from the NTIS Bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning the development and applications of cryogenic refrigeration technology. Citations discuss performance evaluations of specific systems, equipment descriptions, the cooling of instrumentation, superconducting devices, reactor devices, and applications in satellites and spaceborne vehicles. (Contains 250 citations and includes a subject term index and title list.)

NONE

1993-09-01

185

Latest developments in cryogenic safety  

NASA Astrophysics Data System (ADS)

The Cryogenic Safety Manual, sponsored by the British Cryogenics Council, was published over 10 years ago. A new updated version is now available. Some general aspects of cryogenic safety are highlighted, and attention is drawn to some of the more unusual hazardous situations. An awareness of the physical properties of the cryogenic fluids being dealt with is important in directing attention to hazardous situations which may arise. Because of this, the more important properties of the cryogenic fluids are given, such as molecular weight, boiling point and freezing point. From these properties, hazardous situations can be deduced. There are hidden dangers that are not always easy to spot. Some of the unexpected hazards, most of which have led to deaths, are: asphyxiation (anoxia), frost bites and hypothermia, explosions, and combustion. The aim of this publication is to help bring about increased safety in the production and use of cryogenic products through a deeper appreciation of the scientific, technological and administrative steps which must be made if accidents, some fatal, are to be voided in the future.

Webster, T. J.

1983-03-01

186

Latest developments in cryogenic safety  

NASA Technical Reports Server (NTRS)

The Cryogenic Safety Manual, sponsored by the British Cryogenics Council, was published over 10 years ago. A new updated version is now available. Some general aspects of cryogenic safety are highlighted, and attention is drawn to some of the more unusual hazardous situations. An awareness of the physical properties of the cryogenic fluids being dealt with is important in directing attention to hazardous situations which may arise. Because of this, the more important properties of the cryogenic fluids are given, such as molecular weight, boiling point and freezing point. From these properties, hazardous situations can be deduced. There are hidden dangers that are not always easy to spot. Some of the unexpected hazards, most of which have led to deaths, are: asphyxiation (anoxia), frost bites and hypothermia, explosions, and combustion. The aim of this publication is to help bring about increased safety in the production and use of cryogenic products through a deeper appreciation of the scientific, technological and administrative steps which must be made if accidents, some fatal, are to be voided in the future.

Webster, T. J.

1983-01-01

187

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

188

Evaluation of single versus multiple cryogen spray cooling spurts on in vitro model human skin.  

PubMed

Many commercially available dermatologic lasers utilize cryogen spray cooling for epidermal protection. A previous tissue culture study demonstrated that single cryogen spurts (SCS) of 80 ms or less were unlikely to cause cryo-injury in light-skinned individuals. More recently, multiple cryogen spurts (MCS) have been incorporated into commercial devices, but the effects of MCS have not been evaluated. The aim was to study an in vitro tissue culture model and the epidermal and dermal effects of SCS vs patterns of shorter MCS with the same preset total cryogen delivery time (Deltat(c)) and provide an explanation for noted differences. Four different spurt patterns were evaluated: SCS: one 40-ms cryogen spurt; MCS2: two 20-ms cryogen spurts; MCS4: four 10-ms cryogen spurts; MCS8: eight 5-ms cryogen spurts. Actual Deltat(c) and total cooling time (Deltat(Total)) were measured for each spurt pattern. RAFT tissue culture specimens were exposed to cryogen spurt patterns and biopsies were taken immediately and at days 3 and 7. Actual Deltat(c) was increased while Deltat(Total) remained relatively constant as the preset Deltat(c) of 40 ms was delivered as shorter MCS. Progressively more epidermal damage was noted with exposure to the MCS patterns. No dermal injury was noted with either SCS or MCS. For a constant preset Deltat(c) of 40 ms, delivering cryogen in patterns of shorter MCS increased the actual Deltat(c) and consequently the observed epidermal cryo-injury as compared to an SCS. PMID:16133654

Tuqan, Alia T; Kelly, Kristen M; Aguilar, Guillermo; Ramirez-San-Juan, Julio C; Sun, Chung-Ho; Cassarino, David; Derienzo, Damian; Barr, Ronald J; Nelson, J Stuart

2005-09-01

189

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

190

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

191

Cryogenic Electric Motor Tested  

NASA Technical Reports Server (NTRS)

Technology for pollution-free "electric flight" is being evaluated in a number of NASA Glenn Research Center programs. One approach is to drive propulsive fans or propellers with electric motors powered by fuel cells running on hydrogen. For large transport aircraft, conventional electric motors are far too heavy to be feasible. However, since hydrogen fuel would almost surely be carried as liquid, a propulsive electric motor could be cooled to near liquid hydrogen temperature (-423 F) by using the fuel for cooling before it goes to the fuel cells. Motor windings could be either superconducting or high purity normal copper or aluminum. The electrical resistance of pure metals can drop to 1/100th or less of their room-temperature resistance at liquid hydrogen temperature. In either case, super or normal, much higher current density is possible in motor windings. This leads to more compact motors that are projected to produce 20 hp/lb or more in large sizes, in comparison to on the order of 2 hp/lb for large conventional motors. High power density is the major goal. To support cryogenic motor development, we have designed and built in-house a small motor (7-in. outside diameter) for operation in liquid nitrogen.

Brown, Gerald V.

2004-01-01

192

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

193

Reinforced aluminium conductor for cryogenic applications  

SciTech Connect

Extreme purity aluminum has very attractive electrical properties at temperatures below 25 K which makes it competitive with conventional superconductors for cryogenic applications. Besides its inherently low density, its resistivity decreases by several orders of magnitude over its room temperature value thus making it suitable for use in lightweight high current density devices. This paper describes the fabrication of a 99.999% aluminum conductor reinforced by a powder metallurgy (P/M) processed Al-Fe-Ce alloy. Long continuous lengths of composite conductors consisting of 1, 4 and 19 Al filaments have been produced by streamline die hot extrusion and cold working by conventional wire drawing or cold hydrostatic extrusion. Microstructural observations and some limited electrical resistivity and mechanical property data are presented along with an analysis of the contamination of high purity Al conductors by diffusion during annealing.

Premkumar, M.K.; Billman, F.R.; Chakrabarti, D.J.; Dawless, R.K.; Austen, A.R. (Alcoa Lab., Alcoa Center, PA (US))

1991-01-01

194

The integration of liquid cryogen cooling and cryocoolers with superconducting electronic systems  

NASA Astrophysics Data System (ADS)

The need for cryogenic cooling has been a critical issue that has kept superconducting electronic devices from reaching the market place. Even though the performance of many of the superconducting circuits is superior to silicon electronics, the requirement for cryogenic cooling has put the superconducting devices at a serious disadvantage. This paper discusses the process of refrigerating superconducting devices with cryogenic liquids and small cryocoolers. Three types of cryocoolers are compared for vibration, efficiency and reliability. The connection of a cryocooler to the load is discussed. A comparison of using flexible copper straps to carry the heat load and using heat pipe is shown. The type of instrumentation needed for monitoring and controlling the cooling is discussed.

Green, Michael A.

2003-12-01

195

Cryogenics in United States National Programmes.  

National Technical Information Service (NTIS)

The document discusses the importance of cryogenics to national programmes, such as space, health, agriculture, transportation, conservation, and education. The purpose is to demonstrate the inter-relation between the cryogenic industry and United States ...

T. M. Flynn B. W. Birmingham

1968-01-01

196

Cryogenic Technology Development for Exploration Missions.  

National Technical Information Service (NTIS)

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 s...

D. J. Chato

2007-01-01

197

Cryogenic Insulation System for Soft Vacuum.  

National Technical Information Service (NTIS)

The development of a cryogenic insulation system for operation under soft vacuum is presented in this paper. Conventional insulation materials for cryogenic applications can be divided into three levels of thermal performance, in terms of apparent thermal...

S. D. Augustynowicz J. E. Fesmire

1999-01-01

198

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

199

Latest developments in cryogenic safety  

SciTech Connect

The Cryogenic Safety Manual, sponsored by the British Cryogenics Council, was published over 10 years ago. A new updated version is now available. Some general aspects of cryogenic safety are highlighted, and attention is drawn to some of the more unusual hazardous situations. An awareness of the physical properties of the cryogenic fluids being dealt with is important in directing attention to hazardous situations which may arise. Because of this, the more important properties of the cryogenic fluids are given, such as molecular weight, boiling point and freezing point. From these properties, hazardous situations can be deduced. There are hidden dangers that are not always easy to spot. Some of the unexpected hazards, most of which have led to deaths, are: asphyxiation (anoxia), frost bites and hypothermia, explosions, and combustion. The aim of this publication is to help bring about increased safety in the production and use of crygenic products through a deeper appreciation of the scientific, technological and administrative steps which must be made if accidents, some fatal, are to be voided in the future.

Webster, T.J.

1983-03-01

200

Recent achievements with a cryogenic ultra-lightweighted HB-Cesic mirror  

NASA Astrophysics Data System (ADS)

During the past two years, ECM, Germany, together with Mitsubishi Electric Corporation (MELCO), Japan, developed a new carbon-fiber-reinforced SiC material, called HB-Cesic, which possesses superior mechanical and thermal cryogenic properties compared to traditional Cesic. This combination makes HB-Cesic an excellent choice for large cryogenic mirrors, which will be required for future scientific space missions, such as SPICA and DARWIN. ESA contracted Thales Alenia Space (TAS), France, to design a super-lightweighted HB-Cesic mirror with a diameter of 600 mm, isostatic fixations, and a special astigmatism compensation device (ACD) for mirror shape control. The mirror was manufactured by ECM, polished and coated by Socié Européenne de Systèmes Optiques (SESO), France, and tested to cryogenic temperatures by TAS. The measured wave-front error at ambient and cryogenic temperatures demonstrated the excellent homogeneity of HB-Cesic and TAS' expertise in mirror mounting. Furthermore, when thermally actuated, the ACD exhibited perfect control of the mirror shape. This success confirmed HB-Cesic's superior material properties and its applicability to future cryogenic space mirrors. In this paper we describe the design and fabrication process of this cryogenic mirror and give test results at ambient and cryogenic temperatures.

Krödel, Matthias R.; Hofbauer, Peter; Devilliers, Christophe; Sodnik, Zoran; Robert, Patrick

2010-07-01

201

The application of the cryogenic system on the HTS power cable circuit in actual grid  

NASA Astrophysics Data System (ADS)

The 22.9 kV/50 MVA AC HTS power cable system consisted of power cable with 410 m length and cryogenic system has been manufactured by LS Cable & System and installed in Icheon substation of KEPCO grid in the end of 2010. High temperature superconductor only appears the superconductivity at the constant temperate range. So in order to maintain the superconductivity, the cryogenic system is needed. The cryogenic system, the open-loop type, is consisted of the Pressure Control System (PCS), Gas/liquid separator, Circulation Pump, Decompression unit, Filter and so on. Decompression unit is a device that keeps the sub-cooled nitrogen by way of the latent heat of evaporation and includes the heat exchanger. The effectiveness-NTU method is used for the design of the heat exchanger. After installation of the cryogenic system on the site, the test of the cooling capacity of the cryogenic system and commissioning tests were performed. During the grid operation of the HTS power cable system, no major problems have been encountered to this point. The cryogenic system has been operated sufficiently to maintain a stable of the HTS power cable system. This paper will summarize the design of the cryogenic system and the results of the grid operation.

Kim, Yang-Hun; Lee, Su-Kil; Jang, Hyun-Man; Kim, Young-Woong; Lee, Keun-Tae; Choi, Chang-Youl; Ryu, Cheol-Hwi; Kim, Han-Joong; Hwang, Si-Dole; Yang, Hyung-Suk; Sohn, Song-Ho; Lim, Ji-Hyun

2012-12-01

202

HF Cryogenic Low Noise Amplifier  

NASA Astrophysics Data System (ADS)

AL/DTA and IN/SNEC had developed a demonstrator of an RF cryogenic LNA in order to improve the links budget of remote sensing earth station. Working in X band, the cooled LNA allows to reduce efficiently the size of the antennas. So, this solution offers a cheaper alternative to the actual technology used in this area. This demonstrator operates at 80 K cryogenic temperature and makes use of high reliability Stirling cryocooler. The specifications were a noise temperature level lower than 25 K at 50°C room temperature, a gain of 45 dB and MTBF higher than 20.000 hours. The integration of the LNA with the cryogenics is detailed and the thermal performance test results are presented. This work has been performed under CNES R&T contract.

Trollier, T.; Ravex, A.; Butin, D.

2004-06-01

203

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

204

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

205

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

206

FOR REUSABLE LAUNCH VEHICLE CRYOGENIC PROPELLANT TANKS  

Microsoft Academic Search

Analytical and experimental studies conducted at the NASA Langley Research Center for investigating integrated cryogenic propellant tank systems for a Reusable Launch Vehicle are described. The cryogenic tanks are investigated as an integrated tank system. An integrated tank system includes the tank wall, cryogenic insulation, Thermal Protection System (TPS) attachment sub-structure, and TPS. Analysis codes are used to size the

Theodore F. Johnson; Roderick Natividad; H. Kevin Rivers; Russell Smith

207

A versatile laboratory cryogenic plant  

SciTech Connect

The Institute of Theoretical and Experimental physics has designed a versatile cryogenic plant (VCP) which can liquefy helium, hydrogen, neon, and can extract neon from a gaseous neon-helium mixture. It can also be used as a refrigerator for cryostating external objects. The versatile cryogenic plant is schematicized and the refrigerating capacity and VCP control panel are detailed. Characteristic features which distinguish the VCP from other plants are specified. The processes involved in the liquefaction of helium, hydrogen, or neon, and the cryostating and cooling of an external object are explained. The use of the plant showed it to be economic, reliable, and convenient to operate.

Dobrov, V.M.; Marevichev, I.P.; Petrova, Y.B.; Povarov, Y.I.

1983-07-01

208

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

209

A piezoelectric cryogenic heat switch.  

PubMed

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 of about 100-200 at lowest and highest measures temperature were achieved when the positioner applied its maximum force of 8 N, respectively. We discuss the advantages of using this system in cryogenic applications, and estimate the ultimate performance of an ideal PZHS. PMID:24985863

Jahromi, Amir E; Sullivan, Dan F

2014-06-01

210

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

211

Cryogenic wind-tunnel technology  

NASA Technical Reports Server (NTRS)

The cryogenic concept and the advantages it offers with respect to achieving full scale Reynolds number in a moderate size tunnel at reasonable levels of dynamic pressure are described. Aspects which must be considered during the development of a facility that uses gaseous nitrogen as the test gas are examined. These include the properties of nitrogen, particularly at high pressure; isentropic expansion and normal shock flows in nitrogen; real gas ratios; and the problem of condensation. Sources of information on cryogenic technology are cited.

Kilgore, R. A.

1977-01-01

212

Superconducting Planar Devices for Cosmology  

Microsoft Academic Search

To enhance systematics cleaness of a new advanced detection architecture for B-modes detection of the Cosmic Microwave Background polarization and in the framework of the ground based instrument QUBIC (Q and U Bolometric Interferometer for Cosmology), we study planar superconducting devices. Waveguide to microstrip transition, orthomode transducer and phase switches are therefore investigated as well as their cryogenic characterization at

A. Ghribi; B. Bélier; F. Boussaha; E. Bréelle; M. Piat; S. Spinelli; A. Tartari; M. Zannoni

2009-01-01

213

NASA GRC Cryogenic Seal Test Rig Capability  

NASA Technical Reports Server (NTRS)

It has been about six years since any cryogenic seal tests were run at NASA GRC (Glenn Research Center). The Cryogenic Components Lab, where the cryogenic seal test rigs are located, has been shutdown due to the impending expansion of the Cleveland Hopkins International Airport. The current plan is to move the Cryogenic Components Lab (CCL), Cells I and 2 to NASA Plumbrook in Sandusky, Ohio. The purpose of this presentation is to inform the seal community of the cryogenic seal test rig capabilities available at NASA GRC for planning of future programs.

Proctor, Margaret

2001-01-01

214

Discussion on the Cryogenics Safety Manual  

NASA Astrophysics Data System (ADS)

The use of cryogenic liquids is a world-wide activity which involves many different sectors of industry. In 1970 the Safety Panel of the British Cryogenics Council published the Cryogenics Safety Manual which condensed the safety principles of the different industry sectors and set out a guide to good practice. The manual was revised in 1982 and a further revision is proposed for 1988 to reflect current operating practices in the handling of cryogenic liquids. The Manual is now widely regarded as required reading for engineers involved in cryogenic applications. This paper describes the role of the Manual as a training guide and highlights the significant changes proposed in the latest revision.

Currie, J. L.

215

Fastener load tests and retention systems tests for cryogenic wind-tunnel models  

NASA Technical Reports Server (NTRS)

A-286 stainless steel screws were tested to determine the tensile load capability and failure mode of various screw sizes and types at both cryogenic and room temperature. Additionally, five fastener retention systems were tested by using A-286 screws with specimens made from the primary metallic alloys that are currently used for cryogenic models. The locking system effectiveness was examined by simple no-load cycling to cryogenic temperatures (-275 F) as well as by dynamic and static loading at cryogenic temperatures. In general, most systems were found to be effective retention devices. There are some differences between the various devices with respect to ease of application, cleanup, and reuse. Results of tests at -275 F imply that the cold temperatures act to improve screw retention. The improved retention is probably the result of differential thermal contraction and/or increased friction (thread-binding effects). The data provided are useful in selecting screw sizes, types, and locking devices for model systems to be tested in cryogenic wind tunnels.

Wallace, J. W.

1984-01-01

216

Sources of Cryogenic Data and Information  

NASA Astrophysics Data System (ADS)

It is commonly known that cryogenic data, technology, and information are applied across many military, National Aeronautics and Space Administration (NASA), and civilian product lines. Before 1950, however, there was no centralized US source of cryogenic technology data. The Cryogenic Data Center of the National Bureau of Standards (NBS) maintained a database of cryogenic technical documents that served the national need well from the mid 1950s to the early 1980s. The database, maintained on a mainframe computer, was a highly specific bibliography of cryogenic literature and thermophysical properties that covered over 100 years of data. In 1983, however, the Cryogenic Data Center was discontinued when NBS's mission and scope were redefined. In 1998, NASA contracted with the Chemical Propulsion Information Agency (CPIA) and Technology Applications, Inc. (TAI) to reconstitute and update Cryogenic Data Center information and establish a self-sufficient entity to provide technical services for the cryogenic community. The Cryogenic Information Center (CIC) provided this service until 2004, when it was discontinued due to a lack of market interest. The CIC technical assets were distributed to NASA Marshall Space Flight Center and the National Institute of Standards and Technology. Plans are under way in 2006 for CPIA to launch an e-commerce cryogenic website to offer bibliography data with capability to download cryogenic documents.

Mohling, R. A.; Hufferd, W. L.; Marquardt, E. D.

217

Contact Levelmeter for Cryogenic Liquid.  

National Technical Information Service (NTIS)

The operating principle and design of a contact levelmeter for cryogenic liquid are described. The basis of the levelmeter if a 500 omega metallized resistor. A superconductive wire with the 20 mu m diameter and 200 mm length, wound on the resi;tor, is us...

V. N. Pavlov Y. Konichek

1977-01-01

218

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

219

Cryogenic MMIC Low Noise Amplifiers  

NASA Technical Reports Server (NTRS)

Monolithic (MMIC) and discrete transistor (MIC) low noise amplifiers are compared on the basis of performance, cost, and reliability. The need for cryogenic LNA's for future large microwave arrays for radio astronomy is briefly discussed and data is presented on a prototype LNA for the 1 to 10 GZH range along with a very wideband LNA for the 1 to 60 GHz range.

Weinreb, S.; Gaier, T.; Fernandez, J.; Erickson, N.; Wielgus, J.

2000-01-01

220

A cryogenic slab CO laser  

Microsoft Academic Search

A compact capacitive transverse RF-discharge-pumped slab CO laser with cryogenically cooled electrodes, which operates both in the cw and repetitively pulsed regimes, is fabricated. The laser operation is studied in the free running multifrequency regime at the vibrational - rotational transitions of the fundamental (V + 1 V) vibrational bands of the CO molecule in the spectral region from 5.1

Andrei A Ionin; A Yu Kozlov; L V Seleznev; D V Sinitsyn

2009-01-01

221

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

222

Foam shell cryogenic ICF target  

SciTech Connect

A uniform cryogenic layer of DT fuel is maintained in a fusion target having a low density, small pore size, low Z rigid foam shell saturated with liquid DT fuel. Capillary action prevents gravitational slumping of the fuel layer. The saturated shell may be cooled to produce a solid fuel layer.

Darling, Dale H. (Pleasanton, CA)

1987-01-01

223

ILC cryogenic systems reference design  

SciTech Connect

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.; Theilacker, J.; /Fermilab; Parma, V.; Tavian, L.; /CERN

2008-01-01

224

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

225

37-Inch Cryogenic Demonstration Tank.  

National Technical Information Service (NTIS)

This paper presents the design, analysis, fabrication, and testing of a 940 mm (37-inch) diameter by 1,118 mm (44-inch) long cryogenic demonstration tank that was developed and manufactured under a contract for SRS Technologies of Huntsville, Alabama. The...

M. J. Warner D. J. Son D. M. Lester

2000-01-01

226

Level Sensor for Cryogenic Fluids  

NASA Technical Reports Server (NTRS)

Hot wire sensor combined with voltage-comparator circuit monitors liquid level in cryogenic-fluid storage tanks. Sensor circuit adaptable to different liquids and sensors. Constant-current source drives current through sensing probe and fixed resistor. Voltage comparator circuits interpret voltage drops to tell whether probe is immersed in liquid and is current in probe.

Simmons, N. E.; Schroff, R. A.

1983-01-01

227

Titanium alloys for cryogenic technology  

Microsoft Academic Search

The most promising alloy for cryogenic technology of those tested is AT2-2. In the a+ß alloys VT3-1 and VT14 the plasticity decreases sharply at -196°C, and therefore they cannot be recommended for operation below that temperature.

L. P. Rink; L. G. Vertyukova

1967-01-01

228

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

229

Neutron Detection with a Cryogenic Spectrometer  

SciTech Connect

Cryogenic calorimeters are used for x-ray detection because of their exquisite energy resolution and have found application in x-ray astronomy, and the search for dark matter. These devices operate by detecting the heat pulse produced by ionization in an absorber cooled to temperatures below 1 K. Such temperatures are needed to lower the absorber's heat capacity to the point that the deposition of even a few eV results in a measurable temperature excursion. Typical absorbers for dark matter measurements are massive Si or Ge crystals, and, with Ge, have achieved a resolution of 650 eV at 10 keV. Chow, et al., report the measurement of the 60 keV emission from {sup 241}Am with 230 eV resolution using a superconducting tin absorber. Cunningham, et al., also using a superconducting tin absorber, have recently reported a four-fold improvement over Chow. With such results being reported from the x- and gamma-ray world it is natural to examine the possibilities for cryogenic neutron spectroscopy. Such a detector would operate by detecting the heat pulses caused by neutron capture and scattering. To date, {sup 6}LiF has been the absorber of choice because relatively large crystals can be grown, and it is an insulating material with low heat capacity. Silver reports the fabrication of a {sup 6}LiF spectrometer operating at 328 mK and achieving a resolution of 39 keV. De Marcillac reports the fabrication of a spectrometer operating at 80 mK and achieving 16 keV resolution when bombarded with 5 MeV alpha particles. In this paper, we report preliminary results with a TiB{sub 2} absorber exposed to thermal neutrons. In contrast to lithium, whose chemistry selects for LiF as the absorber, boron offers a rich chemistry from which to select materials with high boron content. We will discuss the considerations governing the choice of absorber material as well as the basic considerations needed to understand a cryogenic spectrometer. The capture and scattering reactions in boron and lithium were modeled with MCNP. The modeling results and methods of analysis applicable to lithium- and boron-based spectrometers will be given.

Bell, Z.W.; Lamberti, V.E.; Carpenter, D.A.; Cristy, S.S.

2003-06-23

230

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

231

Design Issues for Cryogenic Cooling of Short Period Superconducting Undulators  

SciTech Connect

Superconducting insertion devices, which produce periodic magnetic fields, have been built and installed in a number of synchrotron-light source storage-rings. For the most part, these devices have been wigglers, which have relatively long period lengths. This report concerns itself with the special cryogenic issues associated with short period undulators. The motivation for considering the incorporation of superconducting technology in insertion device designs is to achieve higher magnetic fields than can be achieved with more conventional permanent magnet technology. Since the peak field decreases sharply with increased magnet gap to period ratio, the cryogenic design of the magnet system is crucial. In particular, the insulation required for a warm vacuum bore device is impractical for short period undulators. This report describes the issues that are related to a cold bore ({approx}4 K) and an intermediate temperature bore (30 to 70 K) designs. The criteria for the use of small cryocoolers for cooling a short period undulator are presented. The problems associated with connecting small coolers to an undulator at 4.2 K are discussed.

Green, M.A.; Dietderich, D.R.; Marks, S.; Prestemon, S.O.; Schlueter, R.D. [Lawrence Berkeley National Laboratory, Berkeley CA 94720 (United States)

2004-06-23

232

Cryogenics and the Human Exploration of Mars  

NASA Technical Reports Server (NTRS)

Current plans within NASA involve extending the human exploration of space from low earth orbit into the solar system, with the first human exploration of Mars presently planned in 2011. Integral to all hum Mars mission phases is cryogenic fluid management. Cryogenic fluids will be required both as propellant and for In-Situ Resource Utilization (ISRU). Without safe and efficient cryogen storage human Mars missions will not be possible. Effective control and handling of cryogenic fluids is the key to affordable Mars missions, and advancing active thermal control technology is synergistic with all of NASA's exploration initiatives and with existing and future instrument cooling programs, including MTPE and Origins. Present mission scenarios for human exploration require cryogenic propellant storage for up to 1700 days and for up to 60 metric tons. These requirements represent increases of an order of magnitude over previous storage masses and lifetimes. The key cryogenic terminology areas to be addressed in human Mars missions are long-term propellant storage, cryogenic refrigeration, cryogenic liquefaction, and zero gravity fluid management. Long-term storage for the thermal control of cryogenic propellants is best accomplished with a mix of passive and active technologies. Passive technologies such as advanced multilayer insulation (MLI) concepts will be combined with the development of active coolers (cryogenic refrigerators). Candidates for long-life active cooling applications include Reverse Turbo-Brayton, Stirling, and Pulse-Tube coolers. The integration of passive and active technologies will form a hybrid system optimized to minimize the launch mass while preserving the cryogenic propellants. Since cryogenic propellants are the largest mass that Mars missions must launch from earth, even a modest reduction in the percentage of propellant carried results in a significant weight saving. This paper will present a brief overview of cryogenic fluid management technology as it applies to the current human Mars mission scenarios.

Salerno, Louis J.; Kittel, Peter; Rasky, Daniel J. (Technical Monitor)

1997-01-01

233

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

234

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

235

Cryogenic processes and equipment - 1984; Proceedings of the Fifth Intersociety Cryogenics Symposium, New Orleans, LA, December 9-14, 1984  

Microsoft Academic Search

The topics of cryogenic processes for LNG and EOR, cryogenic refrigerators, components for cryogenic systems, liquid hydrogen as a fuel, cryogenic processes and equipment for large systems, and cryogenic thermodynamics and heat transfer are discussed. The papers include analysis of process efficiency for baseload LNG production, process efficiency considerations for nitrogen rejection units, design and performance analysis of gas sorption

P. J. Kerney; N. Chatterjee; D. B. Cranwford; M. El-Masri

1984-01-01

236

DC Characteristics of InAs/AlSb HEMTs at Cryogenic Temperatures.  

National Technical Information Service (NTIS)

The Direct Current (DC) properties of 110-nm gate-length InAs/AlSb- based high electron mobility transistors (HEMTs) at cryogenic (30K) and room temperature (300K) were investigated. Compared to 300K, devices at 30K exhibited lower on-resistance (R(sub ON...

E. Lefebvre G. Moschetti M. Malmkvist N. Wadefalk P. Nilsson

2009-01-01

237

First results of a cryogenic optical photon-counting imaging spectrometer using a DROID array  

Microsoft Academic Search

Context. We present the first system test in which we demonstrate the concept of using an array of Distributed Read Out Imaging Devices (DROIDs) for optical photon detection. Aims: After the successful S-Cam 3 detector, the next step in the development of a cryogenic optical photon counting imaging spectrometer under the S-Cam project is to increase the field of view

R. A. Hijmering; P. Verhoeve; D. D. E. Martin; R. Venn; A. van Dordrecht; P. J. Groot

2010-01-01

238

Activated carbon cloth adsorption-cryogenic system to recover toxic volatile organic compounds  

Microsoft Academic Search

There is an emergent need to reduce the emissions of toxic volatile organic compounds (VOCs) to the atmosphere. One strategy to reduce the emissions of VOCs from point sources is to use air pollution control devices on the sources' discharge streams. This paper describes the development of a new activated carbon cloth (ACC) adsorption system that is integrated with cryogenic

Mehrdad Lordgooei; Kelly R. Carmichael; Terrance W. Kelly; Mark J. Rood; Susan M. Larson

1996-01-01

239

Cryogenic refrigeration. (Latest citations from the NTIS data base). Published Search  

SciTech Connect

The bibliography contains citations concerning the technological development and use of cryogenic refrigeration methods and equipment. Performance evaluations of specific systems, equipment descriptions and applications, including the cooling of instrumentation, superconductors, reactor devices, satellites, and other spaceborne vehicles are considered. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1992-05-01

240

32-GHz Cryogenically Cooled HEMT (High Electron Mobility Transitor) Low-Noise Amplifiers.  

National Technical Information Service (NTIS)

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 ou...

J. J. Bautista G. G. Ortiz K. H. G. Duh W. F. Kopp P. Ho

1988-01-01

241

A single chip broadband noise source for noise measurements at cryogenic temperatures  

Microsoft Academic Search

This paper presents the design and performance of a single chip broadband noise source dedicated for on-chip measurements in a cryogenic environment. The noise source is used to generate the two input noise powers Pc and Ph which are required by the commonly used Y-factor method. High accuracy in temperature control and impedance presented to the device under test is

D. Bruch; F. Schafer; M. Seelmann-Eggebert; B. Aja; I. Kallfass; A. Leuther; M. Schlechtweg; O. Ambacher

2011-01-01

242

Experimental results of gain fluctuations and noise in microwave low-noise cryogenic amplifiers  

Microsoft Academic Search

Applications like radio astronomy and space communications require ultimate sensitivity and make use of very particular receivers with state-of-the-art devices. Usually the receivers are cooled at cryogenic temperatures to reduce the noise even further. Noise temperatures of only a few times the quantum limit can be obtained in these conditions. During the past decade, Indium Phosphide HEMTs have demonstrated the

Juan D. Gallego; Isaac López-Fernández; Carmen Diez; Alberto Barcia

2004-01-01

243

The Cryogenic Dark Matter Search  

NASA Astrophysics Data System (ADS)

The Cryogenic Dark Matter Search (CDMS) is an experiment to search for Weakly Interacting Massive Particles (WIMPs). The experiment initially was deployed at a shallow underground site, and is currently deployed at a deep underground site at the Soudan Mine in Minnesota. The detectors operate at cryogenic temperature, and are capable of distinguishing nuclear recoils from WIMP interactions from various backgrounds. The detectors are shielded from background by both active and passive elements. We will describe the components of the overall experiment, and focus on the novel data acquisition system that has been develop to control and monitor the experiment via the World Wide Web. Preliminary signals from the operation at Soudan will be discussed.

Sander, Joel

2004-05-01

244

Cryogenic mechanical design: SPIROU spectrograph  

NASA Astrophysics Data System (ADS)

This paper presents an overview of the PDR level mechanical and opto-mechanical design of the cryogenic spectrograph unit of the nIR spectropolarimeter (SPIROU) proposed as a new-generation instrument for CFHT. The design is driven by the need for high thermo-mechanical stability in terms of the radial velocity (RV) of 1 m/s during one night, with the requirement for thermal stability set at 1 mK/24 hours. This paper describes stress-free design of the cryogenic optical mounts, mechanical design of the custom-build cryostat, mechanical design of the optical bench, and thermal design for 1 mK thermal stability. The thermal budget was calculated using lumped-mass model thermal analysis, implemented in Modelica multi-domain modeling language. Discussion of thermal control options to achieve 1 mK thermal stability is included.

Reshetov, Vlad; Herriot, Glen; Thibault, Simon; Désaulniers, Pierre; Saddlemyer, Les; Loop, David

2012-09-01

245

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

246

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

247

Cryogenic properties of unidirectional composites  

NASA Astrophysics Data System (ADS)

The tensile, compressive, fatigue, thermal expansion, thermal conductivity and specific heat of unidirectional laminates reinforced with boron, alumina, aramid, S-glass, E-glass, and high strength, high modulus and medium modulus carbon fibres are reviewed. The ratio of strength to thermal conductivity is used to assess the suitability of various fibre-reinforced laminates for supporting struts (experiencing compression) or straps (experiencing tension) at cryogenic temperatures. The relationships between laminate properties and reinforcement fibres are discussed.

Reed, R. P.; Golda, M.

248

Munich cryogenic detector development 1995.  

NASA Astrophysics Data System (ADS)

At the Technical University of Munich and the Max Planck Institute of Physics the authors are developing cryogenic detectors for the detection of small deposited energies, for example from the elastic scattering of WIMP dark matter particles, or the absorption of X-rays. Together with the University of Oxford and the Laboratori Nazionali del Gran Sasso they are preparing the CRESST experiment which uses their detectors to search for WIMP dark matter.

Absmaier, C.; Booth, N. E.; Bucci, C.; Buhler, M.; Colling, P.; Cooper, S.; von Feilitzsch, F.; Ferger, P.; Forster, G.; Gabutti, A.; Gutsche, M.; Hettl, P.; Hohne, J.; Hoss, C.; Igalson, J.; Jochum, J.; Kellner, E.; Kemmather, B.; Koch, M.; Kraus, H.; Lalak, Z.; Loidl, M.; Meier, O.; Nagel, U.; Nucciotti, A.; Olechowski, M.; Pokorski, S.; Probst, F.; van der Putte, M. J. J.; Rulofs, A.; Salmon, G. L.; Schanda, U.; Seidel, W.; Sisti, M.; Stodolsky, L.; Stolovich, A.; Zerle, L.

1995-09-01

249

Power stabilized cryogenic sapphire oscillator  

Microsoft Academic Search

Microwave oscillators of exceptional short-term stability have been realized from cryogenic sapphire resonators with loaded Q factors in excess of 109 at 11.9 GHz and 6 K. This has been achieved by a power stabilized loop oscillator with active Pound frequency stabilization. These oscillators have exhibited a fractional frequency stability of 3-4×10-15 for integration times from 0.3 to 100 s.

A. N. Luiten; A. G. Mann; M. E. Costa; D. G. Blair

1995-01-01

250

Cryogenic blackbody radiation calibration source  

NASA Technical Reports Server (NTRS)

A cryogenic blackbody radiation source for providing target temperatures between room temperature and -100 C was designed, fabricated, and tested. This blackbody radiation source is intended for calibration of radiometric infrared imaging systems down to -100 C. The construction and operating principles of this apparatus are described. The long term and short term stability of the radiant source have been investigated. The emittance of the source and the source radiant uniformity have been addressed.

Burkett, Cecil G., Jr.; Daryabeigi, Kamran

1992-01-01

251

Cryogenic Quenching of Steel Revisited  

Microsoft Academic Search

Subject to a continuing debate, cryogenic treatments of alloy steels have been claimed to significantly increase wear resistance and toughness through the interplay of three effects: completing martensitic transformation, promoting uniform precipitation of fine carbides and imparting residual stresses. This study reexamines effects of various heat-treatment schedules including liquid nitrogen (-196oC) and liquid helium (-269 o C) quenching on microstructure

Zbigniew Zurecki

252

Steels for cryogenic power engineering  

Microsoft Academic Search

1.The mechanical properties of the investigated steels at normal and cryogenic temperatures improve when their aluminum content increases to 10%. Further alloying with aluminum causes some impairement of the plastic and ductile properties; this is connected with the formation of a-phase in the structure of the steels.2.Magnetic permeability is practically independent of the temperature in the range 293–4°K because of

B. S. Ermakov; A. Ya. Nikolaich; V. A. Oparin

1986-01-01

253

Cryomechanism: a cryogenic rotating actuator  

NASA Astrophysics Data System (ADS)

Fifteen years ago, CEA started the development of cryogenic rotating actuators for the astrophysical infrared camera (VISIR) that is set on the Very Large Telescope (VLT). At the time of the VISIR first light in 2004, 10 cryogenic rotating actuators, also known as "CryoMechanisms" (CM), were present in the instrument. Today VISIR is still operating and the CM that are actuated several times a day, have no reported failure up to now. In continuation of the VISIR project, CEA undertook space qualification tests with the aim of making the CM compatible with space missions. Relying on this background, a smaller model of the mechanism has been built and tested at cryogenic temperatures. Today, the cryomechanisms are selected for the ESA/EUCLID [1] space mission. The qualification program will run throughout 2014. This paper first describes the VISIR's baseline specification, the CM design and its operation principle. Then, the upgrades for the space constrains are shown and the qualification plan with respect to vibrations, thermal cycling and life testing campaigns is given. Some results of the tests carried out on a qualification model are addressed. At end, the design improvements for the EUCLID project are presented and a summary of the CM capabilities is highlighted.

Barriere, J.-C.; Berthé, M.; Carty, M.; Duboué, B.; Fontignie, J.; Leboeuf, D.; Martignac, J.; Cara, C.; Charon, P.; Durand, G. A.; Bachet, D.

2013-09-01

254

Low-Capacity Cryogenic Refrigeration  

NASA Astrophysics Data System (ADS)

In the early 1980s, Graham Walker wrote his classic two-volume monograph Cryocoolers . Sections of that landmark work have been referenced more often and by more authors than any other cryogenic paper published in the mid-1980s. Nevertheless, in so dynamic a field, an update--one that is compact, inexpensive, and more ranging--is urgently needed. Low-Capacity Cryogenic Refrigeration provides an elementary yet comprehensive introduction to the subject, and features clear discussions of applications to scientific, medical, educational, military, and civil systems. Complementary to the earlier two-volume work, the book covers a wider range of topics and offers a wealth of information about the new developments in the last fifteen years. In addition to descriptions of all the principal methods to achieve low-capacity cryogenic refrigeration, this new volume contains a valuable guide to the literature sources, and references more advanced works. Physicists, chemists, and engineers concerned with low-temperature refrigeration will welcome this new book by an eminent authority in the subject.

Walker, G.; Bingham, E. R.

1994-08-01

255

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

256

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2010 CFR

...Temperature. A flammable cryogenic liquid must be loaded into...shipment of the following cryogenic liquids subject to the following...95 percent parahydrogen), cryogenic liquids must be loaded and...transfer rate test. The insulation system must be...

2010-10-01

257

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2010 CFR

...Temperature. A flammable cryogenic liquid must be loaded into...shipment of the following cryogenic liquids subject to the following...95 percent parahydrogen), cryogenic liquids must be loaded and...transfer rate test. The insulation system must be...

2009-10-01

258

Cryogenic Detectors (Narrow Field Instruments)  

NASA Astrophysics Data System (ADS)

Two cryogenic imaging spectrometer arrays are currently considered as focal plane instruments for XEUS. The narrow field imager 1 (NFI 1) will cover the energy range from 0.05 to 3 keV with an energy resolution of 2 eV, or better, at 500 eV. A second narrow field imager (NFI 2) covers the energy range from 1 to 15 keV with an energy resolution of 2 eV (at 1 keV) and 5 eV (at 7 keV), creating some overlap with part of the NFI 1 energy window. Both narrow field imagers have a 0.5 arcmin field of view. Their imaging capabilities are matched to the XEUS optics of 2 to 5 arcsec leading to 1 arcsec pixels. The detector arrays will be cooled by a closed cycle system comprising a mechanical cooler with a base temperature of 2.5 K and either a low temperature 3He sorption pump providing the very low temperature stage and/or an Adiabatic Demagnetization Refrigerator (ADR). The ADR cooler is explicitly needed to cool the NFI 2 array. The narrow field imager 1} Currently a 48 times 48 element array of superconducting tunnel junctions (STJ) is envisaged. Its operating temperature is in the range between 30 and 350 mK. Small, single Ta STJs (20-50 mum on a side) have shown 3.5 eV (FWHM) resolution at E = 525 eV and small arrays have been successfully demonstrated (6 times 6 pixels), or are currently tested (10 times 12 pixels). Alternatively, a prototype Distributed Read-Out Imaging Device (DROID), consisting of a linear superconducting Ta absorber of 20 times 100 mum2, including a 20 times 20 mum STJ for readout at either end, has shown a measured energy resolution of 2.4 eV (FWHM) at E = 500 eV. Simulations involving the diffusion properties as well as loss and tunnel rates have shown that the performance can be further improved by slight modifications in the geometry, and that the size of the DROIDS can be increased to 0.5-1.0 mm without loss in energy resolution. The relatively large areas and good energy resolution compared to single STJs make DROIDS good candidates for the basic elements of the NFI 1 detector array. With a DROID-based array of 48 times 10 elements covering the NFI 1 field of view of 0.5 arcmin, the number of signal wires would already be reduced by a factor 2.4 compared to a 48 times 48 array of single pixels. While the present prototype DROIDS are still covered with a 480 nm thick SiOx insulation layer, this layer could easily be reduced in thickness or omitted. The detection efficiency of such a device with a 500 nm thick Ta absorber would be >80% in the energy range of 100-3000eV, without any disturbing contributions from other layers as in single STJs. Further developments involve devices of lower Tc-superconductors for better energy resolution and faster diffusion (e.g. Mo). The narrow field imager 2 The NFI 2 will consist of an array of 32 times 32 detector pixels. Each detector is a microcalorimeter which consists of a a superconducting to normal phase transition edge thermometer (transition edge sensor, TES) with an operating temperature of 100 mK, and an absorber which allows a detection efficiency of >90% and a filling factor of the focal plane in excess of 90%. Single pixel microcalorimeters with a Ti/Au TES have already shown an energy resolution of 3.9 eV at 5.89 keV in combination with a thermal response time of 100 mus. These results imply that they the high-energy requirement for XEUS can be met, in terms of energy resolution and response time. It has been demonstrated that bismuth can be applied as absorber material without impeding on the detector performance. Bi increases the stopping power in excess of 90 % and allows for a high filling factor since the absorber is can be modeled in the shape of a mushroom, allowing that the wiring to the detector and the thermal support structure are placed under the hat of the mushroom. In order to realize the NFI 2 detector array, there are two major development areas. Firstly, there is the development of micromachined Si and SiN structures that will provide proper cooling for each of the pixels and the production of small membranes to support the

Hoevers, H.; Verhoeve, P.

259

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

260

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

261

Report on the First VLHC Photon Stop Cryogenic Design Experiment  

NASA Astrophysics Data System (ADS)

As part of Fermilab's study of a Very Large Hadron Collider (VLHC), a water-cooled photon stop was proposed as a device to intercept the synchrotron radiation emitted by the high-energy proton beams in the high-field superconducting magnets with minimal plug-cooling power. Photon stops are radiation absorbers operating at room temperature that protrude into the beam tube at the end of each bending magnet to scrape the synchrotron light emitted by the beam one magnet up-stream. Among the technological challenges regarding photon stops is their cryo-design. The photon stop is water-cooled and operates in a cryogenic environment. A careful cryo-design is therefore essential to enable operation at minimum heat transfer between the room temperature sections and the cryogenic parts. A photon stop cryo-design was developed and a prototype was built. This paper presents the results of the cryogenic experiments conducted on the first VLHC photon-stop prototype.

Geynisman, M.; Bauer, P.; Bossert, R.; Darve, C.; Ewald, K.; Klebaner, A.; Limon, P.; Martinez, A.

2004-06-01

262

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

263

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

264

Network analyzer calibration for cryogenic on-wafer measurements  

SciTech Connect

A cryogenic probe station for on-wafer microwave measurements has been developed at Sandia National Laboratories to explore the basic device physics and characterize advanced components for low-temperature applications. The station was designed to operate over a temperature range of 20 to 300 K with a frequency range of DC to 50 GHz. Due to the vacuum and the low temperature environment, the use of microwave probes and the calibration of network analyzer measurements are somewhat elaborate. This paper presents guidelines for probe use and calibration in this environment.

Hietala, V.M.; Housel, M.S.; Caldwell, R.B.

1994-04-01

265

Experiments in thermosensitive cavitation of a cryogenic rocket propellant surrogate  

NASA Astrophysics Data System (ADS)

Cavitation is a phase-change phenomenon that may appear in practical devices, often leading to loss of performance and possible physical damage. Of particular interest is the presence of cavitation in rocket engine pumps as the cryogenic fluids cavitate in impellers and inducers. Unlike water, which has been studied exhaustively, cryogenic fluids undergo cavitation with significant thermal effect. Past attempts at analyzing this behavior in water have led to poor predictive capability due to the lack of data in the regime defined as thermosensitive cavitation. Fluids flowing near their thermodynamic critical point have a liquid-vapor density ratio that is orders of magnitude less than typical experimental fluids, so that the traditional equation-of-state and cavitation models do not apply. Thermal effects in cavitation have not been fully investigated due to experimental difficulties handling cryogenics. This work investigates the physical effects of thermosensitive cavitation in a model representative of a turbopump inducer in a modern rocket engine. This is achieved by utilizing a room-temperature testing fluid that exhibits a thermal effect equivalent to that experienced by cryogenic propellants. Unsteady surface pressures and high speed imaging collected over the span of thermophysical regimes ranging from thermosensitive to isothermal cavitation offer both quantitative and qualitative insight into the physical process of thermal cavitation. Physical and thermodynamic effects are isolated to identify the source of cavity conditions, oscillations and growth/collapse behavior. Planar laser imaging offers an instantaneous look inside the vapor cavity and at the behavior of the boundary between the two-phase region and freestream liquid. Nondimensional parameters are explored, with cavitation numbers, Reynolds Numbers, coefficient of pressure and nondimensional temperature in a broad range. Results in the form of cavitation regime maps, Strouhal Number of cavity collapse, and cavity length offer a mechanistic analysis of the phenomenon. Linear stability analysis of the boundary is performed, as well as analysis of the thermal effects in the cavity and the oscillatory behavior of the cavity and reentrant jet.

Kelly, Sean Benjamin

266

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

267

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

268

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

269

Designs of pulsed power cryogenic transformers  

Microsoft Academic Search

The Westinghouse Electric Corporation has completed designs of three pulsed power cryogenic transformers of three pulsed power cryogenic transformers for the Los Alamos National Laboratory. These transformers will be configured to transfer their stored energy sequentially to an electro-magnetic launcher and form a three-stage power supply. The pulse transformers will act as two winding energy storage solenoids which provide a

S. K. Singh; C. J. Heyne; D. T. Hackowrth; E. J. Shestak; P. W. Eckels; J. D. Rogers

1988-01-01

270

Cryogenics for Space Observatories: Technology, Requirements, Issues  

NASA Technical Reports Server (NTRS)

The ability to provide cooling at cryogenic temperatures is a critical enabling technology for many of the next generation of space-based observatories and instruments. This report discusses the state of cryogenics technology and identifies and categorizes the various methods of cooling.

Schember, Helene

1989-01-01

271

Large scale cryogenic gravitational wave telescope  

Microsoft Academic Search

Abstract We present here the Large-scale Cryogenic Gravitational wave Tele- scope (LCGT) project which is aimed to improve the sensitivity of the existing gravitational wave projects by ten times. LCGT is the project constructing the km-scale gravitational wave detector in Japan succeeding the TAMA project, which adopts cryogenic mirrors with a higher power laser. We are planing to build it

S. Miyoki; Kazuaki Kuroda; Masatake Ohashi; Daisuke Tatsumi; Hideki Ishizuka; Masa-katsu Fujimoto; Seiji Kawamura; Ryutaro Takahashi; Koji Arai; Mitsuhiro Fukushima; Koichi Waseda; Souichi Telada; Akitoshi Ueda; Takakazu Shintomi; Akira Yamamoto; Toshikazu Suzuki; Yoshio Saito; Tomiyoshi Haruyama; Nobuaki Sato; Kimio Tsubono; Keita Kawabe; Masaki Ando; Ken-ichi Ueda; Hitoki Yoneda; Mitsuru Musha; Norikatsu Mio; Shigenori Moriwaki; Akito Araya; Nobuyuki Kanda; Mike E. Tobar

2005-01-01

272

D0 Cryogenic Auto Dialing Alarm System.  

National Technical Information Service (NTIS)

The Automatic Dialing system purchased by D0 is intended to help make the D0 cryogenic system operate unattended by cryogenic operating personnel. The auto dialer is completely programmable and is voice synthesized. The auto dialer was purchased with 32 b...

D. Markely

1992-01-01

273

Saturated Liquid Densities of Cryogenic Fluids  

Microsoft Academic Search

Experimental saturated liquid densities available in the literature for the cryogenic fluids, hydrogen, neon, argon, nitrogen, oxygen, carbon monoxide, and methane show that their temperature dependence can be expressed by the relationship, With the exception of hydrogen, the saturated liquid density of all the other polyatomic cryogenic fluids can be represented with ? = 0.408 and k = 2.36 giving

G. M. Agrawal; George Thodos

1971-01-01

274

Aerogel beads as cryogenic thermal insulation system  

Microsoft Academic Search

An investigation of the use of aerogel beads as thermal insulation for cryogenic applications was conducted at the Cryogenics Test Laboratory of NASA Kennedy Space Center. Steady-state liquid nitrogen boiloff methods were used to characterize the thermal performance of aerogel beads in comparison with conventional insulation products such as perlite powder and multilayer insulation (MLI). Aerogel beads produced by Cabot

J. E. Fesmire; S. D. Augustynowicz; S. Rouanet

2002-01-01

275

Bonding and Sealing Evaluations for Cryogenic Tanks  

Microsoft Academic Search

Several different cryogenic tank concepts are being considered for reusable launch vehicles (RLV's). Though different tank concepts are being considered, many will require that the cryogenic insulation be evacuated and be bonded to a structure. In this work, an attempt was made to evaluate the effectiveness of maintaining a vacuum on a specimen where foam or honeycomb core was encased

David E. Glass

276

Corner structure for cryogenic insulation system  

Microsoft Academic Search

Cryogenic insulation system for containers for storage of cryogenic liquefied gases such as LNG (liquid natural gas), comprised of a low temperature resistant metal, preferably high nickel steel, membrane or liner supported by a layer of reinforced foam insulation. There is provided at corners, for example at 90° corners, and disposed within the foam insulation layer, a corner structure comprised

Harbaugh

1984-01-01

277

Cryogenic Electrical Insulation and its Advantage  

Microsoft Academic Search

This paper summarizes the cryogenic electrical insulation with polymers and its interesting features. At cryogenic temperature, polymers show high electric strength, extremely higher ac treeing inception voltage, low tandelta, no thermal and chemical degradation, no water tree degradation, very limited space charge injection and resulting high short-circuit treeing inception voltage, etc. Based on these features, we can call polymer at

Masayuki Nagao

2004-01-01

278

Cryogenic fluid management program flight concept definition  

NASA Technical Reports Server (NTRS)

The Lewis Research Center's cryogenic fluid management program flight concept definition is presented in viewgraph form. Diagrams are given of the cryogenic fluid management subpallet and its configuration with the Delta launch vehicle. Information is given in outline form on feasibility studies, requirements definition, and flight experiments design.

Kroeger, Erich

1987-01-01

279

Properties of composite materials for cryogenic applications  

Microsoft Academic Search

Composite materials are used in a wide variety of cryogenic applications because of their unique and highly tailorable properties. These cryogenic applications of composites may be, for the sake of discussion, classified as support structures, vessels, or electrical insulation. Examples of these applications are presented, with a brief discussion of the critical material properties associated with each application. Composite material

J. B Schutz

1998-01-01

280

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

281

Cryogenic recondenser with remote cold box  

Microsoft Academic Search

This patent describes a cryogenic recondenser for recondensing cryogen retained in a storage vessel. The recondenser consists of: cooling means comprising a mechanical refrigerator positioned outside of the storage vessel, the means precooling a volume of gaseous refrigerant; a transfer line leading from the cooling means and removeably inserted into the storage vessel; and a JT valve at an end

A. J. Bartlett; B. R. Andeen; P. A. Lessard

1988-01-01

282

Investigation of cryogenic treatment of UHMWPE  

Microsoft Academic Search

UHMWPE has been used as a bearing material in total joint arthroplasty for many years. Wear of UHMWPE can adversely affect the performance and longevity of orthopaedic implants. Various efforts have been focused on the improvement of UHMWPE properties, including wear resistance. In this study, a cryogenic treatment was investigated for potential improvements of UHMWPE. The cryogenic treatment applied in

H. H. Trieu; L. H. Morris; M. E. Kaufman; R. Hood; L. S. Jenkins

1997-01-01

283

Transition detection studies in the cryogenic environment  

Microsoft Academic Search

Boundary-layer transition detection studies were carried out in the 0.3 Meter Transonic Cryogenic Tunnel on a supercritical airfoil, using an infrared imaging system. The purpose of the experiments was to determine the extent of the temperature range in which commercially available IR systems can detect transition in cryogenic environment. The experiment was designed to take advantage of a combination of

Ehud Gartenberg; William G. Johnson Jr.; Charles B. Johnson; Debra L. Carraway; Robert E. Wright

1990-01-01

284

The cryogenic control system of BEPCII  

Microsoft Academic Search

A superconducting cryogenic system has been designed and deployed in the Beijing Electron- Positron Collider Upgrade Project (BEPCII). The system consists of a Siemens PLC (S7-PLC, Programmable Logic Controller) for the compressor control, an Allen Bradley (AB) PLC for the cryogenic equipments, and the Experimental Physics and Industrial Control System (EPICS) that integrates the PLCs. The system fully automates the

Gang Li; Ke-Xiang Wang; Ji-Jiu Zhao; Ke-Juan Yue; Ming-Hui Dai; Yi-Ling Huang; Bo Jiang

2008-01-01

285

Large Cryogenic Germanium Detector: Final Report.  

National Technical Information Service (NTIS)

Cryogenic Germanium detectors are widely used in high energy physics and astrophysics--for example in direct dark matter searches (such as the Cryogenic Dark Matter Search experiment), or in neutrino-less double-beta decay experiments (such as MAJORANA). ...

V. Mandic

2013-01-01

286

Cryogenic/thermal system for the SIRTF cryogenic telescope assembly  

NASA Astrophysics Data System (ADS)

The Cryogenic Telescope Assembly (CTA) houses the SIRTF Science Instruments and provides them a 1.3 K temperature heat sink. It also provides the telescope, which is maintained at 5.5 K temperature in order to achieve the low photon background required for the 160 micron detector array. This unique cryogenic/thermal system provides the necessary cooling through passive means along with use of vapor cooling from the helium gas vented from the 360 liter superfluid helium cryostat. The cryostat vacuum shell temperature is low enough that the heat load to the helium reservoir is due almost entirely to instrument power dissipation, thus resulting in a predicted lifetime over 5 years. The corresponding helium loss rate is over 7 times lower than achieved by previously flown helium-cooled instrument systems, such as IRAS, COBE, and ISO. This extraordinary performance is made possible by the highly favorable thermal environment achieved in an Earth-trailing solar orbit at a distance of about 0.3 AU from the Earth. Attaining this outer orbit with the slight lift capacity of a Delta-II launch vehicle is made possible by the mass-saving approach of having the telescope outside the cryostat and warm at launch. The general end-to-end system architecture, verification approach, and predicted performance are discussed.

Hopkins, Richard A.; Finley, Paul T.; Schweickart, Russell B.; Volz, Stephen M.

2003-03-01

287

Unpressurized Container For Cryogenic Testing  

NASA Technical Reports Server (NTRS)

Unpressurized cryostat makes mechanical testing of materials at low temperature more convenient. Maintains specimens at temperatures of -400 to -450 degree F without sealing them in gastight, vacuum-insulated container. Easy to insert and remove specimens and attach instrumentation wiring to them. Vents vapor continuously, so no danger of buildup of internal pressure from evaporating cryogenic liquid. Includes two concentric chambers with stainless-steel walls and fiber insulation. Specimen mounted in inner chamber, and such instruments as extensometers and thermocouples attached. Loose lid of polystyrene foam or other suitable material placed over vessel.

Walker, Susan B.

1989-01-01

288

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

289

Cryogenic properties of several copolyesters  

Microsoft Academic Search

Copolyesters of polyethylene terephthalate(PET) and polyethylene-2,6-naphthalene dicarboxylate(PEN) with composition of PET\\/PEN= 100\\/0, 95\\/5, 90\\/10, 85\\/15, 70\\/30, 50\\/50, 30\\/70, 10\\/90, 0\\/100 were prepared. The mechanical properties of uniaxial-drawn films were examined at 83 K and 296 K. PET\\/PEN=90\\/10 copolymer film possessed especially excellent cryogenic properties. It was found to withstand elongations in excess of 40% at stress levels of about 400

O. Yano; A. Kimoto; H. Yamaoka

1997-01-01

290

Cryogenic hydrogen-induced air-liquefaction technologies for combined-cycle propulsion applications  

NASA Technical Reports Server (NTRS)

Given here is a technical assessment of the realization of cryogenic hydrogen induced air liquefaction technologies in a prospective onboard aerospace vehicle process setting. The technical findings related to the status of air liquefaction technologies are reviewed. Compact lightweight cryogenic heat exchangers, heat exchanger atmospheric constituent fouling alleviation measures, para/ortho-hydrogen shift-conversion catalysts, cryogenic air compressors and liquid air pumps, hydrogen recycling using slush hydrogen as a heat sink, liquid hydrogen/liquid air rocket-type combustion devices, and technically related engine concepts are discussed. Much of the LACE work is related to aerospaceplane propulsion concepts that were developed in the 1960's. Emphasis is placed on the Liquid Air Cycle Engine (LACE).

Escher, William J. D.

1992-01-01

291

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

292

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

293

Cryogenic properties of several copolyesters  

SciTech Connect

Copolyesters of polyethylene terephthalate(PET) and polyethylene-2,6-naphthalene dicarboxylate(PEN) with composition of PET/PEN= 100/0, 95/5, 90/10, 85/15, 70/30, 50/50, 30/70, 10/90, 0/100 were prepared. The mechanical properties of uniaxial-drawn films were examined at 83 K and 296 K. PET/PEN=90/10 copolymer film possessed especially excellent cryogenic properties. It was found to withstand elongations in excess of 40% at stress levels of about 400 MPa at 83 K for PET/PEN=90/10 film uniaxial-drawn 5 times. Differential scanning calorimetry(DSC) curves of samples before and after tensile test at 83 K were compared for PET/PEN=90/10 film uniaxial-drawn 5 times. After tensile test at 83 K, the peak position of cold-crystallization shifted and the peak area between the curve and a baseline decreased, indicating that crystallization is allowed to take place during tensile test at 83 K. Dielectric loss tangent was measured in the temperature range from 18 K to the glass transition temperature. The relaxation below 100 K of PET and its copolymers was observed to be dependent on the morphology of samples. On the basis of the results obtained, relationship between the structure of polymers and their cryogenic properties has been discussed.

Yano, O.; Kimoto, A. [Kyoto Institute of Technology (Japan); Yamaoka, H. [Kyoto Univ., Kyoto (Japan)

1997-06-01

294

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

295

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

296

Cryogenic separation of gaseous mixtures  

SciTech Connect

This patent describes a cryogenic separation method for recovering C{sub 1}{sup +} hydrocarbons from cracked hydrocarbon feed gas. It comprises: introducing dry feed gas into a primary dephlegmation zone having a plurality of serially connected, sequentially colder dephlegmator units for separation of feed gas into a primary methane-rich gas stream recovered at low temperature and at least one primary liquid condensate stream rich in C{sub 2}{sup +} hydrocarbon components and containing a minor amount of methane; passing at least one primary liquid condensate stream from the primary dephlegmation zone to serially connected demethanizer fractionators, wherein a moderately low cryogenic temperature is employed in a first demethanizer fractionator unit to recover substantially all of the methane from the primary liquid condensate stream in a first demethanizer overhead vapor stream and to recover a first C{sub 2}{sup +} liquid demethanizer bottoms stream substantially free of methane; further separating at least a portion of the first demethanizer overhead vapor stream in an ultra-low temperature final demethanizer fractionator unit to recover a liquid ethene-rich predominantly C{sub 2} hydrocarbon crude product stream and a final demethanizer ultra-low temperature overhead vapor stream substantially free of C{sub 2}{sup +} hydrocarbons; and fractionating the second crude ethene stream and the first ethene-rich C{sub 2} hydrocarbon crude product stream to obtain a pure ethene product.

McCue, R.H. Jr.; Pickering, J.L. Jr.

1990-02-13

297

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

298

Models for cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

Model requirements, types of model construction methods, and research in new ways to build models are discussed. The 0.3-m Transonic Cryogenic Tunnel was in operation for 16 years and many 2-D airfoil pressure models were tested. In addition there were airfoil models dedicated to transition detection techniques and other specialized research. There were also a number of small 3-D models tested. A chronological development in model building technique is described which led to the construction of many successful models. The difficulties of construction are illustrated by discussing several unsuccessful model fabrication attempts. The National Transonic Facility, a newer and much larger tunnel, was used to test a variety of models including a submarine, transport and fighter configurations, and the Shuttle Orbiter. A new method of building pressure models was developed and is described. The method is centered on the concept of bonding together plates with pressure channels etched into the bond planes, which provides high density pressure instrumentation with minimum demand on parent model material. With care in the choice of materials and technique, vacuum brazing can be used to produce strong bonds without blocking pressure channels and with no bonding voids between channels. Using multiple plates, a 5 percent wing with 96 orifices was constructed and tested in a transonic cryogenic wind tunnel. Samples of test data are presented and future applications of the technology are suggested.

Lawing, Pierce L.

1989-01-01

299

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

300

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

301

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

302

CRYOPUMPING IN CRYOGENIC INSULATIONS FOR A REUSABLE LAUNCH VEHICLE1  

Microsoft Academic Search

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

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

303

Cryogenic refrigeration. (Latest citations from the Aerospace database). Published Search  

SciTech Connect

The bibliography contains citations concerning cryogenic refrigeration or cryocooling. Design, development, testing, and evaluation of cryogenic cooling systems are discussed. Design applications in spacecraft, magnet cooling, superconductors, liquid fuel storage, radioastronomy, and medicine are presented. Material properties at cryogenic temperatures and cryogenic rocket propellants are considered in separate bibliographies. (Contains 250 citations and includes a subject term index and title list.)

NONE

1993-09-01

304

Microstructural study of cryogenically treated En 31 bearing steel  

Microsoft Academic Search

The effect of shallow cryogenic treatment (SCT) and deep cryogenic treatment (DCT) on the microstructure of En 31 bearing steel is studied in the present work. En 31 bearing steel subjected to cryogenic treatment showed more hardness than the conventionally heat treated steel. Fractography analysis of the cryogenic treated steel carried out using scanning electron microscope indicate the presence of

S. Harish; A. Bensely; D. Mohan Lal; A. Rajadurai; Gyöngyvér B. Lenkey

2009-01-01

305

Design, production, and testing of field effect transistors. [cryogenic MOSFETS  

NASA Technical Reports Server (NTRS)

Cryogenic MOSFETS (CRYOFETS), specifically designed for low temperature preamplifier application with infrared extrinsic detectors were produced and comparatively tested with p-channel MOSFETs under matched conditions. The CRYOFETs exhibit lower voltage thresholds, high source-follower gains at lower bias voltage, and lower dc offset source voltage. The noise of the CRYOFET is found to be 2 to 4 times greater than the MOSFET with a correspondingly lower figure of merit (which is established for source-follower amplifiers). The device power dissipation at a gain of 0.98 is some two orders of magnitude lower than for the MOSFET. Further, CRYOFETs are free of low temperature I vs V character hysteresis and balky conduction turn-on effects and operate effectively in the 2.4 to 20 K range. These devices have promise for use on long term duration sensor missions and for on-focal-plane signal processing at low temperatures.

Sclar, N.

1982-01-01

306

D0 Cryogenic Controls I/O Base Power Distribution  

SciTech Connect

The D0 cryogenic control system has 3 I/O bases and 1 25 amp 24vdc power supply. Each I/O base uses both 120 vac and 24 vdc. There are as many as 14 modules in each base, depending on what type of module it may require ac or dc. Then there are as many as 32 devices (instrumentation) per module. There is a power distribution network that provides power to this system. It was configured so that no conductors, devices, or components could carry or receive more current or voltage than they could safely handle. This is done to protect both personel and components from fire, heat, and electric shock.

Markley, D.; /Fermilab

1991-03-09

307

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

308

Highly efficient cryogenic thermal insulation for optical devices and pipelines  

Microsoft Academic Search

Experimental results are presented on the improved efficiency of shielding vacuum thermal insulation (SVTI) with gaskets fabricated from polyethyleneterephthalate (PET) film treated with antistatic substances (surface-active substances (SAS)) for reduction of electrostatic charges and contact heat transfer (by 30% or more).

T. A. Kurskaya; R. S. Mikhal'Chenko; V. F. Getmanets

1995-01-01

309

Throttling Cryogen Boiloff To Control Cryostat Temperature  

NASA Technical Reports Server (NTRS)

An improved design has been proposed for a cryostat of a type that maintains a desired low temperature mainly through boiloff of a liquid cryogen (e.g., liquid nitrogen) at atmospheric pressure. (A cryostat that maintains a low temperature mainly through boiloff of a cryogen at atmospheric pressure is said to be of the pour/fill Dewar-flask type because its main component is a Dewar flask, the top of which is kept open to the atmosphere so that the liquid cryogen can boil at atmospheric pressure and cryogenic liquid can be added by simply pouring it in.) The major distinguishing feature of the proposed design is control of temperature and cooling rate through control of the flow of cryogen vapor from a heat exchanger. At a cost of a modest increase in complexity, a cryostat according to the proposal would retain most of the compactness of prior, simpler pour/fill Dewar-flask cryostats, but would utilize cryogen more efficiently (intervals between cryogen refills could be longer).

Cunningham, Thomas

2003-01-01

310

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

311

Progress on the CUORE Cryogenic System  

SciTech Connect

We give here an update on the CUORE cryogenic system. It consists of a large cryogen-free cryostat cooled by five pulse tubes and one high-power specially designed dilution refrigerator built by Leiden Cryogenics. The cryostat design has been completed and it is presently under construction. The site at the Gran Sasso Underground Laboratory is ready for the installation of the cryostat which is expected to begin by the end of 2009. We discuss here the preliminary results obtained on the performance of the mechanical cryorefrigerators. We also present a measurement of the residual heat leak of the copper which has been selected for the cryostat fabrication.

Martinez, M.; Arnaboldi, C.; Nucciotti, A.; Schaeffer, D.; Sisti, M. [Universita di Milano-Bicocca /INFN Sez. Milano-Bicocca (Italy); Alessandria, F. [INFN Sez. Milano (Italy); Barucci, M. [INFN Sez. Firenze (Italy); Bucci, C. [INFN-Laboratori Nazionali del Gran Sasso (Italy); Frossati, G. [Leiden Cryogenics (Netherlands); De Waard, A. [Kamerlingh Onnes Laboratory, Leiden University (Netherlands); Woodcraft, A. [SUPA, University of Edinburgh (United Kingdom)

2009-12-16

312

Nanosecond cryogenic Yb:YAG disk laser  

NASA Astrophysics Data System (ADS)

A cryogenic Yb:YAG disk laser is modernised to increase its average and peak power. The master oscillator unit of the laser is considerably modified so that the pulse duration decreases to several nanoseconds with the same pulse energy. A cryogenic disk laser head with a flow-through cooling system is developed. Based on two such laser heads, a new main amplifier is assembled according to an active multipass cell scheme. The total small-signal gain of cryogenic cascades is ~108.

Perevezentsev, E. A.; Mukhin, I. B.; Kuznetsov, I. I.; Vadimova, O. L.; Palashov, O. V.

2014-05-01

313

Ambient air heated electrically assisted cryogen vaporizer  

SciTech Connect

A high volume cryogen vaporizer includes a radiator where a working fluid draws heat from ambient air for vaporizing a cryogen in a heat exchanger. An electrical heater is provided for periodically heating the working fluid to defrost the radiator, thereby allowing sustained operation of the vaporizer. When not required for defrosting the radiator, the heater may be operated to heat a working fluid in a circuit separate from that of the radiator, and in which the heated working fluid is used for further elevating the temperature of the vaporized cryogen in a second heat exchanger, thereby making possible a gas output temperature higher than ambient air temperature.

Brigham, W. D.; Dung, N. D.

1985-05-28

314

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

315

On-orbit cryogenic storage and resupply  

NASA Technical Reports Server (NTRS)

Methods of integrating pressure control, liquid acquisition, and liquid transfer concepts for the Cryogenic Fluid Management Facility, a reusable test bed in the Shuttle cargo bay studying the efficient management of cryogens in space, are investigated. Significant design data and criteria for future subcritical cryogenic storage and transfer systems are presented. Technology requirements for liquid storage/supply systems, thermal control systems, and fluid transfer/resupply are addressed, and fluid and thermal analysis pertaining to receiver tank chilldown and no-vent fill of the receiver tank are discussed.

Eberhardt, R. N.; Gille, J. P.; Fester, D. A.

1984-01-01

316

TIMO-2-A cryogenic test bed for the ITER cryosorption pumps  

NASA Astrophysics Data System (ADS)

The Karlsruhe Institute of Technology (KIT) has been carrying out research and development in the field of vacuum cryopumps for nuclear fusion devices over the last decade. Together with the development activities also experience in the operation of the needed cryogenic systems necessary for such type of large scale cryopumps was collected. Due to the specific requirements of a large fusion device, such as ITER, the cryogenic distribution is based on gaseous helium at the needed temperature levels rather than liquid nitrogen or liquid helium. KIT has set up a large scale research facility, called TIMO-2, fully equipped with supercritical helium supply at large flow rates to be able to perform cryogenic tests of components under ITER-relevant conditions. During first test campaigns at TIMO-2 with a large scale model cryopump the ITER cryosorption vacuum pumping concept was successfully validated. After major refurbishments and upgrades, the TIMO-2 facility is now ready for the acceptance tests of the ITER torus cryopump. This paper describes the modified test facility TIMO-2 with particular attention to the available cryogenic supply at different temperature levels. The new 100 K helium supply facility will be described in detail.

Haas, Horst; Day, Christian; Herzog, Friedhelm

2012-06-01

317

Summary of test results for the cryogenic two-phase flight experiment  

NASA Astrophysics Data System (ADS)

This paper presents a brief summary of the flight results for the Cryogenic Two-Phase Flight Experiment (CRYOTP). This experiment was a Hitchhiker-based payload that flew on the space shuttle Columbia in March of 1994 (STS-62). CRYOTP tested two new technologies for advanced cryogenic thermal control; the Space Heat Pipe (SHP), which was a constant conductance cryogenic heat pipe, and the Brilliant Eyes Thermal Storage Unit (BETSU), which was a cryogenic phase-change thermal storage device. Both devices were tested independently during the mission. Analysis of the flight data indicated that the SHP was unable to start in either of two attempts, due to a supercritical startup limit related to the wall material thermal conductivity, parasitic heat leaks, and cryocooler capacity. The BETSU test article was successfully operated with more than 250 hours of on-orbit testing including several cooldown cycles and 56 freeze/thaw cycles. Some degradation was observed with the five tactical cryocoolers used as thermal sinks, and one of the cryocoolers failed completely after 331 hours of operation. Post-flight analysis indicated that this problem was most likely due to failure of an electrical controller internal to the unit.

Swanson, Theodore D.; Buchko, Matthew T.; Bello, Mel; Brennan, Patrick; Stoyanof, Marco M.

1996-03-01

318

Experimental results of gain fluctuations and noise in microwave low-noise cryogenic amplifiers  

NASA Astrophysics Data System (ADS)

Applications like radio astronomy and space communications require ultimate sensitivity and make use of very particular receivers with state-of-the-art devices. Usually the receivers are cooled at cryogenic temperatures to reduce the noise even further. Noise temperatures of only a few times the quantum limit can be obtained in these conditions. During the past decade, Indium Phosphide HEMTs have demonstrated the best noise performance at cryogenic temperatures in the microwave frequency range of all active semiconductor devices, together with extremely low power consumption. For certain applications noise is not the only factor affecting the sensitivity. For example, gain fluctuations may play a dominant role in wide band radiometers. Unfortunately some of the factors that have contributed to improve the noise temperature have degraded the gain fluctuations. The operation at cryogenic temperatures also increases the fluctuations. This paper describes the experimental results obtained at the Centro Astronomico de Yebes (CAY) in the development of wide band cryogenic amplifiers. Special attention is paid to the influence of the bias point in noise and gain fluctuations. InP HEMTs from different foundries were tested. The amplifiers developed will be used in the Herschel ESA mission radiometers and the Atacama Large Millimeter Array (ALMA) receivers.

Gallego, Juan D.; López-Fernández, Isaac; Diez, Carmen; Barcia, Alberto

2004-05-01

319

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

320

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

321

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

322

A brief overview of cryogenics in China  

NASA Astrophysics Data System (ADS)

In this paper general aspects of cryogenics in China are introduced, and applications of cryogenics in the space programme are described briefly, such as its application to the Long March 3 rocket vehicles with LH2/LO2 engines, the development of a 750 dm 3 hr -1 liquid hydrogen plant and railway tank cars with 60 and 70 m 3 capacities. In addition, the progress of various cryogenic techniques in China is presented, such as the FY-1 radiation refrigerator loaded on a meteorology satellite, regenerative cryocoolers of the Gifford-McMahon, Solvay, Vuilleumier, Stirling and pulse tube types, and the KM-3 and KM-4 space simulation facilities. Finally, the paper discusses current education about refrigeration and cryogenics for undergraduates and graduates.

Li, S.-M.

323

Inexpensive cryogenic insulation replaces vacuum jacketed line  

NASA Technical Reports Server (NTRS)

Commercially available aluminized Mylar, cork and fiber glass form a multilayered sealed system and provide rugged and economical field installed insulation for cryogenic /liquid nitrogen or oxygen/ pipe lines in an exposed environment.

Fuchs, C. E.

1967-01-01

324

Measuring the Composition of a Cryogenic Sea  

NASA Astrophysics Data System (ADS)

Titan seas are prime science targets, but compositional measurements require robust sampling techniques. We will discuss the challenges and successful developments towards cryogenic fluid sampling and mass spectrometric measurement of Titan seas.

Trainer, M. G.; Mahaffy, P. R.; Stofan, E. R.; Lunine, J. I.; Lorenz, R. D.

2012-10-01

325

Cryogenic Detectors of Particles: Hopes and Challenges.  

National Technical Information Service (NTIS)

We review the various methods proposed for cryogenic detection of particles, the current status of their development, and their potential applications. 42 refs., 11 figs., 1 tab. (ERA citation 13:015994)

B. Sadoulet

1987-01-01

326

Cryogenic xenon droplets for advanced lithography  

SciTech Connect

A cryogenic xenon droplet production system for use in anadvanced laser plasma source for x-ray lithography has been designed, fabricated, and tested at ORNL. The droplet generator is based on proven (ink jet printer) drop-on-demand.

Gouge, M.J.; Fisher, P.W.

1996-04-01

327

Cryogenic materials selection, availability, and cost considerations  

NASA Technical Reports Server (NTRS)

The selection of structural alloys, composite materials, solder alloys, and filler materials for use in cryogenic models is discussed. In particular, materials testing programs conducted at Langley are described.

Rush, H. F.

1983-01-01

328

Cryogenic target formation using cold gas jets  

DOEpatents

A method and apparatus using cold gas jets for producing a substantially uniform layer of cryogenic materials on the inner surface of hollow spherical members having one or more layers, such as inertially imploded targets are disclosed. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on an inner surface of the spherical member. Basically the method involves directing cold gas jets onto a spherical member having one or more layers or shells and containing the cryogenic material, such as a deuterium-tritium (DT) mixture, to freeze the contained material, momentarily heating the spherical member so as to vaporize the contained material, and quickly refreezing the thus vaporized material forming a uniform layer of cryogenic material on an inner surface of the spherical member. 4 figs.

Hendricks, C.D.

1980-02-26

329

The National Measurement System for Cryogenics.  

National Technical Information Service (NTIS)

The study of the National Measurement System showed that the Cryogenics Division of NBS provides almost every category of measurement and data service that NBS itself provides: not just an instrumentation system (including, for example, pressure, temperat...

T. M. Flynn

1975-01-01

330

Advanced cryogenics for cutting tools. Final report.  

National Technical Information Service (NTIS)

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 test...

L. J. Lazarus

1996-01-01

331

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

332

Cryogenic Fluid Film Bearing Tester Development Study.  

National Technical Information Service (NTIS)

Conceptual designs were developed for the determination of rotordynamic coefficients of cryogenic fluid film bearings. The designs encompassed the use of magnetic and conventional excitation sources as well as the use of magnetic bearings as support beari...

J. K. Scharrer B. T. Murphy L. A. Hawkins

1993-01-01

333

Cryogenic target formation using cold gas jets  

DOEpatents

A method and apparatus using cold gas jets for producing a substantially uniform layer of cryogenic materials on the inner surface of hollow spherical members having one or more layers, such as inertially imploded targets. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on an inner surface of the spherical member. Basically the method involves directing cold gas jets onto a spherical member having one or more layers or shells and containing the cryogenic material, such as a deuterium-tritium (DT) mixture, to freeze the contained material, momentarily heating the spherical member so as to vaporize the contained material, and quickly refreezing the thus vaporized material forming a uniform layer of cryogenic material on an inner surface of the spherical member.

Hendricks, Charles D. (Livermore, CA) [Livermore, CA

1980-01-01

334

Cryogenic target formation using cold gas jets  

DOEpatents

A method and apparatus using cold gas jets for producing a substantially uniform layer of cryogenic materials on the inner surface of hollow spherical members having one or more layers, such as inertially imploded targets. By vaporizing and quickly refreezing cryogenic materials contained within a hollow spherical member, a uniform layer of the materials is formed on an inner surface of the spherical member. Basically the method involves directing cold gas jets onto a spherical member having one or more layers or shells and containing the cryogenic material, such as a deuterium-tritium (DT) mixture, to freeze the contained material, momentarily heating the spherical member so as to vaporize the contained material, and quickly refreezing the thus vaporized material forming a uniform layer of cryogenic material on an inner surface of the spherical member.

Hendricks, Charles D. (Livermore, CA) [Livermore, CA

1981-01-01

335

Cryogenic fatigue data developed for Inconel 718  

NASA Technical Reports Server (NTRS)

Data were obtained on the cryogenic fatigue properties of Inconel 718 bar using axial loading and rotating beam fatigue tests. Results also disclosed the fatigue properties of Inconel 718 sheet materials.

Schmidt, E. H.

1967-01-01

336

Impact resistant tank for cryogenic fluids  

Microsoft Academic Search

Pittsburgh-Des Moines Steel Co.'s new aboveground double-wall LNG tank is unique in both maintaining an effective seal for cryogenic liquids and providing impact resistance to withstand explosions or impact loads caused by accidents such as a nearby airplane crash. The impact-resistant tank has an inner wall and bottom made of suitable cryogenic metal reinforced by annular reinforcing rings. Between the

J. Terlesky; H. E. Muller; J. C. Murphy; H. F. Honath

1977-01-01

337

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

338

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

339

Development of cryogenic rotatable heat transfer joints  

NASA Astrophysics Data System (ADS)

A summary of cryogenic rotatable heat transfer joint technology development, at Rockwell International Space Division, is presented. Starting with the flight qualified radiative joint on the RM-20B IR sensor of the early 70's, leading to rotatable heat pipe joint, gas conductive joints, rolling-contact-conductance joints, and the more recent work on development and evaluation of cryogenic rotatable seals and mechanical interfaces. Potential applications, joint design optimization, heat transfer, seal leakage and torque test data are presented.

Sadunas, J. A.; Backovsky, Z. F.; Wilson, D. E.

1992-07-01

340

Multichip module packaging for cryogenic computers  

Microsoft Academic Search

A high-speed multichip module for cryogenic data processing systems has been developed using new packaging and cooling techniques. The cryogenic multichip module achieves a cycle time of 1.5 ns by using high-speed high-electron-mobility-transistor (HEMT) ICs, low-stress cryo-multichip module (MCM) packaging, and a stable cryocooling system. The HEMT multichip module consists of 20 3 K-gate HEMT ICs on a high-density, 115-mm2

H. Yamamoto

1991-01-01

341

DIII-D cryogenics control system status  

Microsoft Academic Search

The DIII-D cryogenics system provides liquid helium for various auxiliary systems at the DIII-D tokamak facility. The system described here executes control and supervision of the cryogenics plant and associated load systems which include four neutral beam injectors, superconducting magnets, and an in-vessel tokamak cryocondensation pump. The recent addition of this divertor cryopump represented a major increase in the scope

G. L. Campbell; J. J. Harris; K. M. Schaubel

1993-01-01

342

Cryogenic engineering and superconductor technology; Proceedings of the 14th International Cryogenic Engineering Conference and International Cryogenic Materials Conference, Kiev, Ukraine, June 8-12, 1992  

Microsoft Academic Search

Consideration is given to application concepts of small regenerative cryocoolers in superconducting magnet systems, thermoelectric materials for Peltier cryogenic coolers, closed-cycle liquid helium refrigerators, built-in cryogenic control fixtures with electric drive, large cryogenic helium systems for superconducting magnets, low temperature adsorptive hydrogen isotope separation, cryogenic thermometry for space testing systems, performance of parallel flow He-II heat exchangers, and transient heat

P. Komarek; C. Rizzuto

1992-01-01

343

The double electrostatic ion ring experiment: A unique cryogenic electrostatic storage ring for merged ion-beams studies  

Microsoft Academic Search

We describe the design of a novel type of storage device currently under construction at Stockholm University, Sweden, using purely electrostatic focussing and deflection elements, in which ion beams of opposite charges are confined under extreme high vacuum cryogenic conditions in separate ``rings'' and merged over a common straight section. The construction of this double electrostatic ion ring experiment uniquely

R. D. Thomas; H. T. Schmidt; G. Andler; M. Björkhage; M. Blom; L. Brännholm; E. Bäckström; H. Danared; S. Das; N. Haag; P. Halldén; F. Hellberg; A. I. S. Holm; H. A. B. Johansson; A. Källberg; G. Källersjö; M. Larsson; S. Leontein; L. Liljeby; P. Löfgren; B. Malm; S. Mannervik; M. Masuda; D. Misra; A. Orbán; A. Paál; P. Reinhed; K.-G. Rensfelt; S. Rosén; K. Schmidt; F. Seitz; A. Simonsson; J. Weimer; H. Zettergren; H. Cederquist

2011-01-01

344

Large signal modelling of cryogenically cooled GaAs field effect transistors for low phase noise oscillator design  

Microsoft Academic Search

We present an extensive study of microwave FET nonlinear electrical properties at liquid nitrogen temperature. Pulsed measurement, together with low frequency noise measurements and S-parameters measurements, have been used to extract a large signal model of a previously selected HEMT device. This model is particularly dedicated to microwave low phase noise cryogenic oscillators design

O. Llopis; J. Verdier; J. M. Dienot; P. Andre; R. Plana; J. Graffeuil

1994-01-01

345

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

346

Cryogenic ion chemistry and spectroscopy.  

PubMed

The use of mass spectrometry in macromolecular analysis is an incredibly important technique and has allowed efficient identification of secondary and tertiary protein structures. Over 20 years ago, Chemistry Nobelist John Fenn and co-workers revolutionized mass spectrometry by developing ways to non-destructively extract large molecules directly from solution into the gas phase. This advance, in turn, enabled rapid sequencing of biopolymers through tandem mass spectrometry at the heart of the burgeoning field of proteomics. In this Account, we discuss how cryogenic cooling, mass selection, and reactive processing together provide a powerful way to characterize ion structures as well as rationally synthesize labile reaction intermediates. This is accomplished by first cooling the ions close to 10 K and condensing onto them weakly bound, chemically inert small molecules or rare gas atoms. This assembly can then be used as a medium in which to quench reactive encounters by rapid evaporation of the adducts, as well as provide a universal means for acquiring highly resolved vibrational action spectra of the embedded species by photoinduced mass loss. Moreover, the spectroscopic measurements can be obtained with readily available, broadly tunable pulsed infrared lasers because absorption of a single photon is sufficient to induce evaporation. We discuss the implementation of these methods with a new type of hybrid photofragmentation mass spectrometer involving two stages of mass selection with two laser excitation regions interfaced to the cryogenic ion source. We illustrate several capabilities of the cryogenic ion spectrometer by presenting recent applications to peptides, a biomimetic catalyst, a large antibiotic molecule (vancomycin), and reaction intermediates pertinent to the chemistry of the ionosphere. First, we demonstrate how site-specific isotopic substitution can be used to identify bands due to local functional groups in a protonated tripeptide designed to stereoselectively catalyze bromination of biaryl substrates. This procedure directly reveals the particular H-bond donor and acceptor groups that enforce the folded structure of the bare ion as well as provide contact points for noncovalent interaction with substrates. We then show how photochemical hole-burning involving only vibrational excitations can be used in a double-resonance mode to systematically disentangle overlapping spectra that arise when several conformers of a dipeptide are prepared in the ion source. Finally, we highlight our ability to systematically capture reaction intermediates and spectroscopically characterize their structures. Through this method, we can identify the pathway for water-network-mediated, proton-coupled transformation of nitrosonium, NO(+) to HONO, a key reaction controlling the cations present in the ionosphere. Through this work, we reveal the critical role played by water molecules occupying the second solvation shell around the ion, where they stabilize the emergent product ion in a fashion reminiscent of the solvent coordinate responsible for the barrier to charge transfer in solution. Looking to the future, we predict that the capture and characterization of fleeting intermediate complexes in the homogeneous catalytic activation of small molecules like water, alkanes, and CO2 is a likely avenue rich with opportunity. PMID:23972279

Wolk, Arron B; Leavitt, Christopher M; Garand, Etienne; Johnson, Mark A

2014-01-21

347

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

348

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

349

The Cryogenic Anticoincidence Detector for ATHENA-XMS  

NASA Astrophysics Data System (ADS)

The TES cryogenic detectors, due to their high spectral resolution and imaging capability in the soft X-ray domain, are the reference devices for the next proposed space missions whose aims are to characterize the spectra of faint or diffuse sources. ATHENA is the re-scoped IXO mission, and one of its focal plane instrument is the X-ray Microcalorimeter Spectrometer (XMS) working in the energy range 0.3-10 keV. XMS will be able to achieve the proposed scientific goals if a background lower than 0.02 cts/cm2/s/keV is guaranteed. The studies performed by GEANT4 simulations depict a scenario where it is mandatory to use an active Anti-Coincidence (AC) to reduce the expected background in the L2 orbit down to the required level. This is possible using a cryogenic AC detector able to provide a rejection efficiency of about 99%. We are developing for this purpose a TES-based detector made by Silicon absorbers (total assembled area about 1 cm2 and 300 ?m thick) and sensed by a Ir:Au TES. All the work done for IXO is applicable to ATHENA, with more margins due to the smaller area required for the detector. Here we present the results obtained from different samples, as a step towards the final detector design.

Macculi, C.; Colasanti, L.; Lotti, S.; Natalucci, L.; Piro, L.; Bagliani, D.; Biasotti, M.; Gatti, F.; Torrioli, G.; Barbera, M.; La Rosa, G.; Mineo, T.; Perinati, E.

2012-06-01

350

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

351

32-GHz cryogenically cooled HEMT low-noise amplifiers  

NASA Astrophysics Data System (ADS)

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 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.

Duh, K. H. George; Kopp, William F.; Ho, Pin; Chao, Pane-Chane; Ko, Ming-Yih; Smith, Phillip M.; Ballingall, James M.; Bautista, J. Javier; Ortiz, Gerardo G.

1989-08-01

352

32-GHz cryogenically cooled HEMT low-noise amplifiers  

SciTech Connect

The cryogenic noise temperature performance of a two-stage and a three-state 32-GHz HEMT amplifier has been evaluated. The Amplifiers utilize quarter-micrometer conventional AlGaAs/GaAs HEMT devices, employ 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 to 12 {Kappa}. Across the measurement band, the amplifiers displayed a broad-band response, and the noise temperature was observed to decrease by a factor of ten in cooling from 300 to 15 {Kappa}. The lowest noise temperature measured for the two-stage amplifier at 32 GHz was 35 {Kappa} with an associated gain of 16.5 dB, while the three-stage measured 39 {Kappa} with an associated gain of 26 dB. It was further observed that both amplifiers were insensitive to light.

Duh, K.H.G.; Kopp, W.F.; Ho, P.; Chao, P.C.; Kao, M.Y.; Smith, P.M.; Ballingall, J.M. (General Electric Co., Syracuse, NY (USA). Electronics Lab.); Bautista, J.J.; Ortiz, G.G. (Jet Propulsion Lab., Pasadena, CA (USA))

1989-08-01

353

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 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.

Duh, K. H. George; Kopp, William F.; Ho, Pin; Chao, Pane-Chane; Ko, Ming-Yih; Smith, Phillip M.; Ballingall, James M.; Bautista, J. Javier; Ortiz, Gerardo G.

1989-01-01

354

On 32-GHz cryogenically cooled HEMT low-noise amplifiers  

NASA Astrophysics Data System (ADS)

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.

1988-11-01

355

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

356

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

357

First results of a cryogenic optical photon counting imaging spectrometer using a DROID array  

Microsoft Academic Search

Context. In this paper we present the first system test in which we\\u000ademonstrate the concept of using an array of Distributed Read Out Imaging\\u000aDevices (DROIDs) for optical photon detection. Aims. After the successful S-Cam\\u000a3 detector the next step in the development of a cryogenic optical photon\\u000acounting imaging spectrometer under the S-Cam project is to increase the

R. A. Hijmering; P. Verhoeve; D. D. E. Martin; R. Venn; A. van Dordrecht; P. J. Groot

2009-01-01

358

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

359

On the collapse of drain IV characteristics in modulation-doped FET's at cryogenic temperatures  

Microsoft Academic Search

The collapse of the drain current-voltage characteristics of modulation-doped field-effect transistors (MODFET's) at cryogenic temperatures, previously thought to be unavoidable, has been investigated. The results indicate that the mechanism responsible for the collapse is dependent on both the device fabrication steps and the parameters of crystal growth. Bulk Al(x)Ga(1-x)As FET's fabricated in laboratory exhibited little or no collapse in the

R. Fischer; T. J. Drummond; J. Klem; W. Kopp; T. S. Henderson; D. Perrachione; H. Morkoc

1984-01-01

360

Dark current measurements on a superconducting cavity using a cryogenic current comparator.  

PubMed

This paper presents nondestructive dark current measurements of tera electron volt energy superconducting linear accelerator cavities. The measurements were carried out in an extremely noisy accelerator environment using a low temperature dc superconducting quantum interference device based cryogenic current comparator. The overall current sensitivity under these rough conditions was measured to be 0.2 nA/Hz(1/2), which enables the detection of dark currents of 5 nA. PMID:21280820

Geithner, R; Neubert, R; Vodel, W; Seidel, P; Knaack, K; Vilcins, S; Wittenburg, K; Kugeler, O; Knobloch, J

2011-01-01

361

A 2.3-GHz cryogenically cooled HEMT amplifier for DSS 13  

NASA Technical Reports Server (NTRS)

A prototype 2.3 GHz (S band) high electron mobility transistor (HEMT) amplifier/closed cycle refrigerator (CCR) system was installed in the DDS-13 feedcone, replacing the 2.3 GHz maser. The amplifier is cryogenically cooled to a physical temperature of 12 K and provides 31.5 K antenna system noise temperature and 29 dB of gain. The HEMT device used in the amplifier is a prototype.

Tanida, L.

1987-01-01

362

A 2.3-GHz cryogenically cooled HEMT amplifier for DSS 13  

NASA Astrophysics Data System (ADS)

A prototype 2.3 GHz (S band) high electron mobility transistor (HEMT) amplifier/closed cycle refrigerator (CCR) system was installed in the DDS-13 feedcone, replacing the 2.3 GHz maser. The amplifier is cryogenically cooled to a physical temperature of 12 K and provides 31.5 K antenna system noise temperature and 29 dB of gain. The HEMT device used in the amplifier is a prototype.

Tanida, L.

1987-11-01

363

Cryogenic, HEMT, low-noise receivers for 1.3 to 43 GHz range  

Microsoft Academic Search

After a review of recent progress in cryogenically cooled high-electron-mobility-transistor (HEMT) devices and amplifiers, a description is given of the construction and performance of a number of receiver front-ends built for radioastronomy applications using very-low-noise HEMT amplifiers and small, closed-cycle 13 K refrigerators. The noise temperature of receivers, measured at the room temperature circular waveguide input (for example, 10.5 K

S. Weinreb; M. W. Pospieszalski; R. Norrod

1988-01-01

364

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

365

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

366

Active Costorage of Cryogenic Propellants for Exploration  

NASA Technical Reports Server (NTRS)

Long-term storage of cryogenic propellants is a critical requirement for NASA's effort to return to the moon. Liquid hydrogen and liquid oxygen provide the highest specific impulse of any practical chemical propulsion system, and thus provides the greatest payload mass per unit of launch mass. Future manned missions will require vehicles with the flexibility to remain in orbit for months, necessitating long-term storage of these cryogenic liquids. For decades cryogenic scientific satellites have used cryogens to cool instruments. In many cases, the lifetime of the primary cryogen tank has been extended by intercepting much of the heat incident on the tank at an intermediate-temperature shield cooled either by a second cryogen tank or a mechanical cryocooler. For an LH2/LO2 propellant system, a combination of these ideas can be used, in which the shield around the LO2 tank is attached to, and at the same temperature as, the LO2 tank, but is actively cooled so as to remove all heat impinging on the tank and shield. This configuration eliminates liquid oxygen boil-off and cuts the liquid hydrogen boil-off to a small fraction of the unshielded rate. This paper studies the concept of active costorage as a means of long-term cryogenic propellant storage. The paper describes the design impact of an active costorage system for the Crew Exploration Vehicle (CEV). This paper also compares the spacecraft level impact of the active costorage concept with a passive storage option in relation to two different scales of spacecraft that will be used for the lunar exploration effort, the CEV and the Earth Departure Stage (EDS). Spacecraft level studies are performed to investigate the impact of scaling of the costorage technologies for the different components of the Lunar Architecture and for different mission durations.

Canavan, Edgar R.; Boyle, Rob; Mustafi, Shuvo

2008-01-01

367

Effects of cryogenic treatment on wear behavior of D6 tool steel  

Microsoft Academic Search

In this paper, the effects of cryogenic treatment on the wear behavior of D6 tool steel were studied. For this purpose, two temperatures were used: ?63°C as shallow cryogenic temperature and ?185°C as deep cryogenic temperature. The effects of cryogenic temperature (Shallow and deep), cryogenic time (kept at cryogenic temperature for 20 and 40h) and stabilization (kept at room temperature

A. Akhbarizadeh; A. Shafyei; M. A. Golozar

2009-01-01

368

Cryogenic pulsed inductive microwave magnetometer  

NASA Astrophysics Data System (ADS)

A cryogenic pulsed inductive microwave magnetometer is used to characterize the switching dynamics in thin-film magnetic materials at low temperatures and microwave frequencies. The system is contained inside a 20-cm-diam ultrahigh vacuum chamber and cooled by a cryopump that allows measurements between 20 and 350 K. A temperature controller regulates the sample temperature using two silicon diodes as sensors. Applied magnetic fields of up to 36 kA/m (450 Oe) are generated by a four-pole, water-cooled electromagnet with independent control of each axis. Magnetic switching in the sample is driven by high-speed current step pulses in a coplanar waveguide structure with the sample placed in a flip-chip configuration. A 20 GHz sampling oscilloscope is used to record the dynamics of the magnetic reorientation. The switching dynamics are given for a 10-nm-thick Ni-Fe film at 30 K in response to a 1 kA/m field step.

Kos, A. B.; Nibarger, J. P.; Lopusnik, R.; Silva, T. J.; Celinski, Z.

2003-05-01

369

Cryogenic High-Conductivity Cavity  

NASA Astrophysics Data System (ADS)

A refrigerated cavity saves a considerable amount of driving power owing to the cryo enhancement in conductivity. An L-band copper cavity is expected to have about six times the room-temperature Q factor at 40 K, which is nowadays easily attainable by a compact refrigerator, and therefore reduce the required power to one sixth. The reduction in operation power enables the use of solid state amplifiers as a compact and handy power source. The combination of the cryogenic high-conductivity cavities and the solid state amplifiers, with each cavity fed separately by each amplifier, provides a flexible accelerating system applicable to a wide range of particle velocities. A post-accelerator for deuterons has been proposed as the first pilot system employing individually driven cryo cavities, which should serve to realize a simultaneous acceleration of protons and deuterons in the KEK PS injector. A 400 MHz copper cavity, equivalent to each of the unit cavities composing the post-accelerator, passed a test operation at liquid nitrogen temperature with a 20 Hz-repetition 0.3 ms-width pulsed power up to the peak value 5 kW giving rise to the specified voltage. It will be subjected to further operation at lower temperature.

Morozumi, Yuichi

1997-05-01

370

Millimeter-wave, cryogenically-coolable amplifiers using AlInAs\\/GaInAs\\/InP HEMTs  

Microsoft Academic Search

The cryogenic performance of AlInAs\\/GaInAs\\/InP 0.1- mu m high-electron-mobility transistors (HEMTs) is reported. Collapse-free DC operation is observed down to the ambient temperature of 18 K. The application of these devices to Q- and E-band low-noise, cryogenically coolable amplifiers is demonstrated. The measured noise temperature of 15 K (noise figure of 0.2 dB) for a multistage 40-45-GHz amplifier with 33

M. W. Pospieszalski; W. J. Lakatosh; R. Lai; K. L. Tan; D. C. Streit; P. H. Liu; R. M. Dia; J. Velebir

1993-01-01

371

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

372

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

373

Cryogenic Fluid Management Experiment (CFME) Trunnion Verification Testing.  

National Technical Information Service (NTIS)

The Cryogenic Fluid Management Experiment (CFME) was designed to characterize subcritical liquid hydrogen storage and expulsion in the low-g space environment. The CFME has now become the storage and supply tank for the Cryogenic Fluid Management Facility...

W. J. Bailey D. A. Fester

1983-01-01

374

Preparation of fine-particles at cryogenic temperatures  

NASA Technical Reports Server (NTRS)

Flash freezing process yields gelling agent for use at cryogenic temperatures. Vaporized material, diluted with an inert gas, is injected below the surface of an agitated cryogenic liquid. This method disperses particles of chlorine trifluoride in liquid oxygen difluoride.

Globus, H.

1970-01-01

375

Experimentation for the Maturation of Deep Space Cryogenic Refueling Technologies.  

National Technical Information Service (NTIS)

This report describes the results of the 'Experimentation for the Maturation of Deep Space Cryogenic Refueling Technology' study. This study identifies cryogenic fluid management technologies that require low-gravity flight experiments bring technology re...

D. J. Chato

2008-01-01

376

Energy Efficient Cryogenics on Earth and in Space  

NASA Technical Reports Server (NTRS)

The Cryogenics Test Laboratory, NASA Kennedy Space Center, works to provide practical solutions to low-temperature problems while focusing on long-term technology targets for energy-efficient cryogenics on Earth and in space.

Fesmire, James E.

2012-01-01

377

Superconducting Meissner Effect Bearings for Cryogenic Turbomachines. Phase 2.  

National Technical Information Service (NTIS)

This is the final report of a Phase II SBIR project to develop -Meissner effect bearings for miniature cryogenic turbomachines. The bearing system was designed for use in miniature cryogenic turboexpanders in reverse-Brayton-cycle cryocoolers. These cryoc...

J. A. Valenzuela J. L. Martin

1994-01-01

378

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

379

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

380

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

381

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

382

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

383

Tests of VPHGs in the NIR for use at cryogenic temperatures  

NASA Astrophysics Data System (ADS)

We report on the performances measured at room temperature, before and after a cryogenic cooling cycle, of a set of NIR Volume Phase Holographic Gratings (VPHGs) manufactured at the Miguel Hernández University (UMH, Elche, Spain) aimed at their use in astronomical instrumentations. VPHGs are novel optical components which can replace standard ruled transmission gratings, offering some advantages. Instead of a surface modulation, a diffraction index modulation printed in a volume of material generates the diffraction according to the required specifications. While VPHGs are becoming an option for instruments working in the optical regime at room temperature, their use is still minimal in the NIR wavebands due to the stringent requirements impose by the cryogenic environment. But their good properties in terms of high transmission and compact mechanical design are kept even in cryogenic, so efforts to develop such devices functional at cryogenic temperatures are underway in several institutions. We report results on transmission of newly manufactured VPHGs. These results were achieved through a collaborative effort within the European network OPTICON WP6, “New Materials and Processes in Astronomical Instrumentation”, and whose participating institutions are Instituto de Astrofísica de Canarias (IAC), Universidad Miguel Hernández, Osservatorio Astronomico di Brera (INAF) and Politecnico di Milano.

Insausti, Maider; Garzón, Francisco; Madrigal, Roque; Fimia, Antonio

2012-09-01

384

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

385

The cryogenic transonic wind tunnel for high Reynolds number research  

NASA Technical Reports Server (NTRS)

Based on theoretical studies and experience with a low speed cryogenic tunnel and with the transonic cryogenic tunnel, the cryogenic wind tunnel concept has been shown to offer many advantages with respect to the attainment of full scale Reynolds number at reasonable levels of dynamic pressure in a ground based facility. The unique modes of operation available in a pressurized cryogenic tunnel make possible for the first time the separation of Mach number, Reynolds number, and aeroelastic effects.

Kilgore, R. A.; Adcock, J. B.; Ray, E. J.

1976-01-01

386

A Reference Guide for Cryogenic Properties of Materials  

SciTech Connect

A thorough knowledge of the behavior of materials at cryogenic temperatures is critical for the design of successful cryogenic systems. Over the past 50 years, a tremendous amount of material properties at cryogenic temperatures have been measured and published. This guide lists resources for finding these properties. It covers online databases, computer codes, conference proceedings, journals, handbooks, overviews and monographs. It includes references for finding reports issued by government laboratories and agencies. Most common solids and fluids used in cryogenics are covered.

Weisend, John G

2003-09-16

387

Cryogenic refrigeration, volume 3. A bibliography with abstracts  

Microsoft Academic Search

Cryogenic cooling of electronic equipment, infrared equipment, cryogenic storage vessels, magnetohydrodynamic generators, and superconducting magnets, coils, rotating machinery, and transmission lines is reported. Marine refrigeration of liquefied natural gas, cryogenic heat pipes, cryogenic heat transfer, and space applications are studied. Methods investigated include adiabatic demagnetization, electrocaloric effect, Joule-Thomson effect, thermoelectric cooling, and Crayton, Claude, Gifford-McMahon, Sterling, and Vuilleumier cycles. This

W. E. Reed

1978-01-01

388

Cryogenic refrigeration, volume 3. A bibliography with abstracts  

Microsoft Academic Search

Topics in the cited reports include cryogenic cooling of electronic equipment, infrared equipment, cryogenic storage vessels, magnetohydrodynamic generators, and superconducting magnets, coils, rotating machinery, and transmission lines. Marine refrigeration of liquefied natural gas, cryogenic heat pipes, cryogenic heat transfer, and space applications are studied. Methods investigated include adiabatic demagnetization, electrocaloric effect, Joule-Thomson effect, thermoelectric cooling, and Crayton, Claude, Gifford-McMahon, Sterling,

W. E. Reed

1979-01-01

389

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

390

Closed cryogenic cooling system without moving parts  

SciTech Connect

This patent describes a closed system with no moving parts for providing cryogenic cooling to a load heat exchanger, comprising: an electrochemical pump for pressurizing an ionizable cryogenic gas; a high-pressure flow path adapted to direct pressurized gas from the electrochemical pump to the load heat exchanger. The path includes a first heat exchanger for cooling the gas to below its inversion temperature and a Joule-Thomson flow restrictor to further cool the gas to a cryogenic temperature for delivery to the load heat exchanger; and, a low-pressure flow path adapted to receive the gas from the load heat exchanger and to return the gas to the electrochemical pump. The low-pressure flow path includes a second heat exchanger for warming the gas to a predetermined temperature.

Gross, S.

1987-06-09

391

Advanced long term cryogenic storage systems  

NASA Technical Reports Server (NTRS)

Long term, cryogenic fluid storage facilities will be required to support future space programs such as the space-based Orbital Transfer Vehicle (OTV), Telescopes, and Laser Systems. An orbital liquid oxygen/liquid hydrogen storage system with an initial capacity of approximately 200,000 lb will be required. The storage facility tank design must have the capability of fluid acquisition in microgravity and limit cryogen boiloff due to environmental heating. Cryogenic boiloff management features, minimizing Earth-to-orbit transportation costs, will include advanced thick multilayer insulation/integrated vapor cooled shield concepts, low conductance support structures, and refrigeration/reliquefaction systems. Contracted study efforts are under way to develop storage system designs, technology plans, test article hardware designs, and develop plans for ground/flight testing.

Brown, Norman S.

1987-01-01

392

Long term storage of cryogens in space  

NASA Astrophysics Data System (ADS)

Experimental design procedures leading to the configuration of a space-based cryogenic fluids test system are reported. Large quantities of cryogenic fluids are expected to be required in space for cooling systems, chemical and electrical OTVs, and resupply tankers. The design was guided by the necessity for representative storage and supply systems to be compatible with the Shuttle. Consideration was given to liquid hydrogen, oxygen, methane, and argon containers and concommitant fluid dynamics, thermal, and structural analyses. A 5% initial ullage was included for the liquids, except for methane, which was calculated at 8.9%. The Ar, CH4, and O2 tanks were set at 12.5 cu m, while the H2 tank was 37.4 cu m. The orbital experiment is required to provide actual thermal stabilization lags in a zero-g environment. Details of the Cryogenic Fluid Management Facility test module for flight on board the Shuttle are presented.

Fester, D. A.; Eberhardt, R. N.

1982-06-01

393

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

394

Cryogenic Amplifier Based Receivers at Submillimeter Wavelengths  

NASA Technical Reports Server (NTRS)

The operating frequency of InP high electron mobility transistor (HEMT) based amplifiers has moved well in the submillimeter-wave frequencies over the last couple of years. Working amplifiers with usable gain in waveguide packages has been reported beyond 700 GHz. When cooled cryogenically, they have shown substantial improvement in their noise temperature. This has opened up the real possibility of cryogenic amplifier based heterodyne receivers at submillimeter wavelengths for ground-based, air-borne, and space-based instruments for astrophysics, planetary, and Earth science applications. This paper provides an overview of the science applications at submillimeter wavelengths that will benefit from this technology. It also describes the current state of the InP HEMT based cryogenic amplifier receivers at submillimeter wavelengths.

Chattopadhyay, Goutam; Reck, Theodore and; Schlecht, Erich; Lin, Robert; Deal, William

2012-01-01

395

Hybrid Joule-Thomson cryogenic cooler  

NASA Astrophysics Data System (ADS)

The evolution of the hybrid Joule-Thomson cryogenic cooler is considered, taking into account the Hampson liquifier, the Hampson liquifier with precooler, and the hybrid cryogenic cooler. The Hampson liquifier uses a Joule-Thomson expansion of compressed gas to produce a liquid cryogen. A greater fraction of the gas is converted to liquid if the gas is precooled prior to expansion. The adaption of the process to spaceflight applications is discussed. Attention is given to the range of possible operating temperatures in a hybrid cooler, the refrigeration to mass ratio, problems of fluid management, cooler features and advantages, and applications of the cooler related to maintaining detector and detector-related instruments at the required low temperatures.

Annable, R. V.

396

Temperature monitor and alarm for cryogenic instruments  

NASA Astrophysics Data System (ADS)

Internal temperatures in filled cryostats must be continuously monitored to preserve the health and safety of hardware and personnel. The accidental response of cryogenic gases into the atmosphere pose a health threat and, if the gases are flammable, may lead to an explosion. One indication of an imminent cryogen release is the sudden increase in cryogen temperature. Although there are many data acquisition systems and temperature monitoring products commercially available, these systems lack the portability and safety features required during cryostat qualification tests and transport. This paper describes a temperature monitor and alarm circuit developed for the Spirit II solid hydrogen cryostat program. The instrument is battery-operated, accurate, portable, and intrinsically safe in an explosive atmosphere.

Thatcher, John B., Jr.; Keliher, Pat; Jeanpierre, Carlos

1994-06-01

397

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

398

Preliminary Commissioning of Cryogenic System of Besiii  

NASA Astrophysics Data System (ADS)

A helium cryogenic system with cooling capacity of 1 kW at 4.5 K was set up at Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing. This helium refrigeration system is dedicated for the cooling of two superconducting radio frequency (SRF) cavities, two interaction region superconducting quadrupole magnets (SCQ), the Beijing Spectrometer III (BESIII) solenoid magnet (SSM), which are the key items of the upgrade project of Beijing Electron-Positron Collider (BEPCII). Commissioning with the SSM and SCQ magnets has been carried out, which will be introduced in this paper. The cryogenic system of BESIII magnet showed very robust as SSM quenched. This paper presents the overall status and some test results of the cryogenic system.

Zong, Z. G.; Liu, L. Q.; Zhang, L.; Li, S. P.; He, K.; Xiong, L. Y.

2008-03-01

399

49 CFR 173.318 - Cryogenic liquids in cargo tanks.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Cryogenic liquids in cargo tanks. 173.318...Preparation and Packaging § 173.318 Cryogenic liquids in cargo tanks. (a) General...A cargo tank may not be loaded with a cryogenic liquid colder than the design...

2009-10-01

400

49 CFR 173.318 - Cryogenic liquids in cargo tanks.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Cryogenic liquids in cargo tanks. 173.318...Preparation and Packaging § 173.318 Cryogenic liquids in cargo tanks. (a) General...A cargo tank may not be loaded with a cryogenic liquid colder than the design...

2010-10-01

401

49 CFR 173.316 - Cryogenic liquids in cylinders.  

Code of Federal Regulations, 2010 CFR

...used to transport oxygen, cryogenic liquid unless the parts are...to transport any flammable cryogenic liquid. (6) Each cylinder...installed and located so that the cooling effect of the contents during...Each cylinder containing a cryogenic liquid must have a...

2009-10-01

402

49 CFR 173.316 - Cryogenic liquids in cylinders.  

Code of Federal Regulations, 2010 CFR

...used to transport oxygen, cryogenic liquid unless the parts are...to transport any flammable cryogenic liquid. (6) Each cylinder...installed and located so that the cooling effect of the contents during...Each cylinder containing a cryogenic liquid must have a...

2010-10-01

403

Cryogenic Propellant Storage and Transfer (CPST) Technology Demonstration Mission (TDM)  

NASA Technical Reports Server (NTRS)

Objectives: 1) Store cryogenic propellants in a manner that maximizes their availability for use regardless of mission duration. 2) Efficiently transfer conditioned cryogenic propellant to an engine or tank situated in a microgravity environment. 3) Accurately monitor and gauge cryogenic propellants situated in a microgravity environment.

Chojnacki, Kent

2013-01-01

404

The effect of cryogenic cooling on grinding forces  

Microsoft Academic Search

Grinding forces are important parameters to judge the performance of any grinding process. Cryogenic cooling in grinding is a new concept to control the high grinding zone temperature without polluting the environment. The paper presents a hypothesis on the mechanics of grinding under cryogenic cooling. Experiments have been carried out to study the effect of cryogenic cooling on grinding forces

S. Paul; A. B. Chattopadhyay

1996-01-01

405

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

406

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

407

Performance evaluation of cryogenically treated tungsten carbide tools in turning  

Microsoft Academic Search

This paper describes a study on the effects of cryogenic treatment of tungsten carbide. Cryogenic treatment has been acknowledged by some as a means of extending the tool life of many cutting tool materials, but little is known about the mechanism behind it. Thus far, detailed studies pertaining to cryogenic treatment have been conducted only on tool steels. However, tungsten

A. Y. L. Yong; K. H. W. Seah; M. Rahman

2006-01-01

408

Deep Cryogenic Treatment Improves Wear Resistance of En 31 Steel  

Microsoft Academic Search

Cryogenic treatment is an inexpensive supplementary process to conventional heat treatment, which improves the tribological properties of steels. A study has been made on the effect of cryogenic treatment on En 31 steels done at different stages of heat treatment. It is observed that through cryogenic treatment the wear can be decreased by a maximum of 75% depending on the

A. Joseph Vimal; A. Bensely; D. Mohan Lal; K. Srinivasan

2008-01-01

409

The Fast Alternative Cryogenic Experiment Testbed  

NASA Astrophysics Data System (ADS)

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 multi-channel 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. This work was carried out by the Jet Propulsion Laboratory, California Institute of Technology under contract to the National Aeronautics and Space Administration. The work was funded by NASA Microgravity Research Division.

Nash, Alfred

410

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

411

Adjustable expandable cryogenic piston and ring  

DOEpatents

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 is subject to external control. This control may be made manually or it may be made automatically in response to instruments that sense the amount of blow-by of the cryogenic fluid and adjust for an optimum blow-by.

Mazur, Peter O. (Aurora, IL); Pallaver, Carl B. (Woodridge, IL)

1980-01-01

412

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

413

Improvement of Carbon Nanotubes using Cryogenic Treatment  

NASA Astrophysics Data System (ADS)

Functional improvement of single-walled carbon nanotubes coated on polyimide Kapton HN was studied by means of cyclic cryogenic treatment. Immersing in liquid nitrogen at 77 K joining in heat annealing at 500 K induced the increase of D-G ratio and electrical conductivity in conjecture to the partial remedial junction with the coexisted stiction on surface. The coated thickness was deliberately able to adjust associated with cycling number of cryogenic treatment through the sequential detachment from the outmost layer owing to the axial shrunken effect by new atomic cross links at defects derived from the close bonding distance.

Kim, Dae-Weon; Jang, Eui-Yun; Lee, Seung-Min; Kim, Wal-jun; Lee, Jong-Hoon; Kleiman, Jacob

2007-12-01

414

Ultra-high heat flux cooling characteristics of cryogenic micro-solid nitrogen particles and its application to semiconductor wafer cleaning technology  

NASA Astrophysics Data System (ADS)

The ultra-high heat flux cooling characteristics and impingement behavior of cryogenic micro-solid nitrogen (SN2) particles in relation to a heated wafer substrate were investigated for application to next generation semiconductor wafer cleaning technology. The fundamental characteristics of cooling heat transfer and photoresist removal-cleaning performance using micro-solid nitrogen particulate spray impinging on a heated substrate were numerically investigated and experimentally measured by a new type of integrated computational-experimental technique. This study contributes not only advanced cryogenic cooling technology for high thermal emission devices, but also to the field of nano device engineering including the semiconductor wafer cleaning technology.

Ishimoto, Jun; Oh, U.; Guanghan, Zhao; Koike, Tomoki; Ochiai, Naoya

2014-01-01

415

Microstructural Stability of 316 Stainless Steel During Long Term Exposure to High Magnetic Fields at Cryogenic Temperatures  

SciTech Connect

The effect of long term exposure to high magnetic fields at cryogenic temperatures on the microstructural stability of austenitic stainless steel was investigated. Three samples of SUS316 were prepared. One was as-machined, the second was solution heat-treated, and the last was solution heat-treated followed by a sensitization heat treatment. The samples were attached to the helical coil cover of the Large Helical Device, which is a large plasma experimental device operating with a superconducting magnet system. The maximum magnetic field the samples experienced was about 2.56 T for over 100 cycles during which time the temperature was kept at about 4.5 K for approximately 300 days. Before and after the exposure, the susceptibility was measured by a superconducting quantum interference device and it was confirmed that the austenitic phase was stable and did not produce any additional martensite by the long term exposure to the high magnetic fields at cryogenic temperatures.

Nishimura, A. [National Institute for Fusion Science, Toki, Gifu, 509-5292 (Japan); Kakeshita, T. [Graduate School of Engineering, Osaka University, Suita, Osaka, 565-0871 (Japan)

2004-06-28

416

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

417

InAs/AlSb HEMTs for cryogenic LNAs at ultra-low power dissipation  

NASA Astrophysics Data System (ADS)

Properties of the InAs/AlSb high electron mobility transistor, essential for the design of a cryogenic low-noise amplifier (LNA) operating at low power dissipation, have been studied. Upon cooling from 300 K to 77 K, the dc transconductance g m was enhanced by 30% at a drain-source voltage V DS of 0.1 V. The gate current leakage showed a strong reduction of the Schottky current component at 77 K. Compared to 300 K, the cut-off frequency f T and maximum oscillation frequency fmax showed a significant improvement at 77 K with a peak f T ( fmax) of 167 (142) GHz at V DS = 0.2 V. The suitability of the Sb HEMT for a cryogenic LNA design up to 50 GHz, operating at low dc power dissipation, was investigated through the extraction of the NF tot,min figure of merit. It was found that the best device performance in terms of noise and gain is achieved at a low V DS of 0.16 V resulting in a minimum NF tot,min of 0.6 dB for a frequency of 10 GHz when operating at 77 K. A benchmarking between the Sb HEMT and an InP HEMT has been conducted highlighting the device improvement in noise and gain required to reach today's state-of-the-art cryogenic LNAs.

Moschetti, Giuseppe; Wadefalk, Niklas; Nilsson, Per-Åke; Roelens, Yannick; Noudeviwa, Albert; Desplanque, Ludovic; Wallart, Xavier; Danneville, Francois; Dambrine, Gilles; Bollaert, Sylvain; Grahn, Jan

2011-10-01

418

Development of a miniature cryogenic fluid circuit and a cryogenic micropump  

Microsoft Academic Search

This article presents the development of a miniaturized cryogenic fluid circuit for distributed cooling of low-temperature tracking detectors in high-energy physics (HEP). The heart of the circuit is a prototype cryogenic micropump. This volumetric pump is compatible with cooling powers of about 10–100W, and capable of producing pressure heads of up to around 0.3MPa. Besides detector and electronics cooling in

S. Grohmann; R. Herzog; T. O. Niinikoski; B. Perea-Solano; H. Quack; G. Vögele; E. Wobst

2005-01-01

419

Cryogenic Technology, part 1. [conference proceedings; cryogenic wind tunnel design and instrumentation  

NASA Technical Reports Server (NTRS)

Different engineering problems associated with the design of mechanisms and systems to operate in a cryogenic environment are discussed. The focal point for the entire engineering effort was the design of the National Transonic Facility, which is a closed-circuit cryogenic wind tunnel. The papers covered a variety of mechanical, structural, and systems design subjects including thermal structures insulation systems, noise, seals, and materials.

1980-01-01

420

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

421

Temperature control of a cryogenic bath  

NASA Technical Reports Server (NTRS)

Foreign gas introduced into vapor phase above liquid region cools cryogenic baths. Equipment consists of gas tank and cover of styrofoam. Helium is considered the best choice to produce cooling, though any gas with boiling point lower than that of bath liquid may be used.

Asher, I. M.

1972-01-01

422

Optical testing cryogenic thermal vacuum facility  

Microsoft Academic Search

The construction of a turnkey cryogenic vacuum test facility was recently completed. The facility will be used to measure and record the surface profile of large diameter and 540 kg optics under simulated space conditions. The vacuum test chamber is a vertical stainless steel cylinder with a 3.5 diameter and a 7 m tangent length. The chamber was designed to

Patrick W. Dohogne; Warren A. Carpenter

1990-01-01

423

Capacitance based mass metering for cryogenic fluids  

Microsoft Academic Search

This paper describes a method for measuring the mass of cryogenic fluids in on-board rocket propellant tanks or ground storage tanks. Linear approximations to the Clausius–Mossotti relationship serve as the foundation for a capacitance based mass sensor, regardless of fluid density stratification or tank shape. Sensor design considerations are presented along with the experimental results for a capacitance based mass

Mark A. Nurge; Robert Youngquist; Deron Walters

2003-01-01

424

Cryogenic testing of the TPC superconducting solenoid  

SciTech Connect

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 remote helium compressor with a full flow liquid nitrogen purification station, 400 meters of high pressure supply and low pressure return lines; and locally a CTi Model 2800 refrigerator with two Sulzer gas bearing turbines, the TPC magnet control dewar, 70 meters of transfer lines, and the TPC thin superconducting solenoid magnet. In addition, there is a conditioner (liquid nitrogen heat exchangers and gas heaters) system for cooldown and warmup of the magnet. This report describes the local cryogenic system and describes the various steps in the cooldown and operation of the TPC magnet. The tests were successful in that they showed that the TPC magnet could be cooled down in 24 hours and the magnet could be operated on the refrigerator or a helium pump with adequate cooling margin. The tests identified problems with the cryogenic system and the 2800 refrigerator. Procedures for successful operation and quenching of the superconducting magnet were developed. 19 references.

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

1983-06-01

425

LASERS: A cryogenic slab CO laser  

Microsoft Academic Search

A compact capacitive transverse RF-discharge-pumped slab CO laser with cryogenically cooled electrodes, which operates both in the cw and repetitively pulsed regimes, is fabricated. The laser operation is studied in the free running multifrequency regime at the vibrational - rotational transitions of the fundamental (V + 1 --> V) vibrational bands of the CO molecule in the spectral region from

Andrei A. Ionin; A. Yu Kozlov; L. V. Seleznev; D. V. Sinitsyn

2009-01-01

426

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

427

The International Cryogenic Materials Conference (ICMC 2004)  

Microsoft Academic Search

The International Cryogenic Materials Conference entitled `Materials Processing, Microstructures and Critical Current of Superconductors' was hosted by the Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, New South Wales, Australia, on 10-13 February 2004.The objective of this ICMC topical conference was to bring together world experts in materials processing, characterization and microstructure control of modern superconductors, to discuss

2004-01-01

428

KRION-2 Cryogenic Electron Beam Ionizer.  

National Technical Information Service (NTIS)

The construction of the ''KRION-2'' cryogenic electron beam ionizer is described in short. Results of investigations of ion behaviour in the electron beam of the ionizer and experiments on the production of highly charged state ions are considered. The cr...

E. D. Donets V. P. Ovsyannikov

1980-01-01

429

Cryogenic Pipe Freezing - A Theoretical Model.  

National Technical Information Service (NTIS)

A theoretical simplified model for cryogenic pipe freezing, which is based on a steady-state approximation, has been developed in this work. A comparison with experimental results shows a relatively good agreement with the heat flux data obtained from dir...

H. Tinoco

1988-01-01

430

Lecture Notes on Vacuum and Cryogenics.  

National Technical Information Service (NTIS)

This Manual is brought out with the hope that it will be a helpful reference to all those who are working or interested in the area of vacuum and cryogenics. A total of 12 papers are included. These deal with Pressure Measurement, Production of Very Low T...

1979-01-01

431

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

432

Status and applications of cryogenic detectors  

Microsoft Academic Search

An overview of the actual technical status and achievements of different types of cryogenic detectors is given. Typical applications in several fields are discussed with emphasis put on appropriate nuclear experiments for the planned Princeton facility. The possibility of implementation in low temperature nuclear orientation experiments will be explored.

M. M. Lowry; E. van Walle; J. B. Peterson; F. P. Calaprice

1988-01-01

433

Status and applications of cryogenic detectors  

Microsoft Academic Search

An overview of the actual technical status and achievements of different types of cryogenic detectors is given. Typical applications\\u000a in several fields are discussed with emphasis put on appropriate nuclear experiments for the planned Princeton facility. The\\u000a possibility of implementation in low temperature nuclear orientation experiments will be explored.

M. M. Lowry; E. van Walle; J. B. Peterson; F. P. Calaprice

1988-01-01

434

Contact conductivity of cryogenic heat insulation materials  

Microsoft Academic Search

Results are presented of an experimental investigation by the method of the electrothermal analogy for the contact heat transfer in different kinds of cryogenic thermal insulation and empirical dependences are obtained that permit execution of a qualitative, and in a number of cases, even a quantitative estimate of the contribution of the contact conductivity to the total heat transport through

S. B. Mil'Man; M. G. Velikanova

1991-01-01

435

Cryogenic Insulation Strength and Bond Tester.  

National Technical Information Service (NTIS)

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 p...

P. H. Schuerer J. H. Ehl W. P. Prasthofer

1983-01-01

436

Cryogenic cable insulated with oil impregnated paper  

Microsoft Academic Search

The breakdown properties of oil impregnated paper insulation are very significant at low temperature, especially around the freezing temperature of oil. We proposed a new insulating method for cryogenic cable insulated with the oil impregnated paper. The conductor of the cable we designed has a coolant channel inside and its electrical insulation is located between two thermal insulators to be

Z. Iwata; N. Ichiyanagi; E. Kawai

1977-01-01

437

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

438

The Cryogenic Test Bed experiments: Cryogenic heat pipe flight experiment CRYOHP (STS-53). Cryogenic two phase flight experiment CRYOTP (STS-62). Cryogenic flexible diode flight experiment CRYOFD  

NASA Technical Reports Server (NTRS)

This paper presents an overview of the Cryogenic Test Bed (CTB) experiments including experiment results, integration techniques used, and lessons learned during integration, test and flight phases of the Cryogenic Heat Pipe Flight Experiment (STS-53) and the Cryogenic Two Phase Flight Experiment (OAST-2, STS-62). We will also discuss the Cryogenic Flexible Diode Heat Pipe (CRYOFD) experiment which will fly in the 1996/97 time frame and the fourth flight of the CTB which will fly in the 1997/98 time frame. The two missions tested two oxygen axially grooved heat pipes, a nitrogen fibrous wick heat pipe and a 2-methylpentane phase change material thermal storage unit. Techniques were found for solving problems with vibration from the cryo-collers transmitted through the compressors and the cold heads, and mounting the heat pipe without introducing parasitic heat leaks. A thermally conductive interface material was selected that would meet the requirements and perform over the temperature range of 55 to 300 K. Problems are discussed with the bi-metallic thermostats used for heater circuit protection and the S-Glass suspension straps originally used to secure the BETSU PCM in the CRYOTP mission. Flight results will be compared to 1-g test results and differences will be discussed.

Thienel, Lee; Stouffer, Chuck

1995-01-01

439

Microwave oscillators incorporating cryogenic sapphire dielectric resonators  

Microsoft Academic Search

Progress is reported on efforts to develop a commercially-viable high purity X-band signal source incorporating a cryogenic sapphire dielectric resonator. The resonator design is of the whispering gallery type to take advantage of the excellent electromagnetic field confinement offered by this geometry. Complications resulting from the high spurious mode density of this type of resonator have been eliminated by developing

R. C. Taber; C. A. Flory

1995-01-01

440

Optimum Input Leads for Cryogenic Apparatus  

Microsoft Academic Search

Electrical leads carrying currents into cryogenic apparatus also introduce heat. Even with an ideal Carnot cycle, the mechanical power needed to remove this heat can be one hundred or more times the heat flow itself. If the currents and hence the input leads are heavy, a very sizeable refrigerator may be required. In this article the configuration of the leads

Richard McFee

1959-01-01

441

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

442

Cryogenic recondenser with remote cold box  

SciTech Connect

This patent describes a cryogenic recondenser for recondensing cryogen retained in a storage vessel. The recondenser consists of: cooling means comprising a mechanical refrigerator positioned outside of the storage vessel, the means precooling a volume of gaseous refrigerant; a transfer line leading from the cooling means and removeably inserted into the storage vessel; and a JT valve at an end of the transfer line in the storage vessel, the precooled refrigerant being transferred in the transfer line from the cooling means to the JT valve in heat exchange relation with returning refrigerant and being expanded through the JT valve to form a liquid-gas cryogen mixture within the end of the transfer line which is in heat exchange relation with boil-off from the cryogen retained in the storage vessel such that the boil off is cooled and recondensed; refrigerant being returned to the cooling means through the transfer line in a manner in which the returning refrigerant is in heat exchange relation with the refrigerant being transferred to the JT valve.

Bartlett, A.J.; Andeen, B.R.; Lessard, P.A.

1988-08-30

443

The DIII-D cryogenic system upgrade  

Microsoft Academic Search

The original DIII-D cryogenic system was commissioned in 1981 and was used to cool the cryopanel arrays for three hydrogen neutral beam injectors. Since then, new demands for liquid helium have arisen including: a fourth neutral beam injector, ten superconducting magnets for the electron cyclotron heating gyrotrons, and more recently, the advanced divertor cryopump which resides inside the tokamak vacuum

K. M. Schaubel; G. J. Laughon; G. L. Campbell; A. R. Langhorn; N. C. Stevens; M. L. Tupper

1993-01-01

444

The DIII-D cryogenic system upgrade  

Microsoft Academic Search

The original DIII-D cryogenic system was commissioned in 1981 and was used to cool the cryopanel arrays for three hydrogen neutral beam injectors. Since then, new demands for liquid helium have arisen including: a fourth neutral beam injector, ten superconducting magnets for the electron cyclotron heating gyrotrons, and more recently, the advanced diverter cryopump which resides inside the tokamak vacuum

K. M. Schaubel; G. J. Laughon; G. L. Campbell; A. R. Langhorn; N. C. Stevens; M. L. Tupper

1993-01-01

445

DIII-D cryogenic system upgrade.  

National Technical Information Service (NTIS)

The original DIII-D cryogenic system was commissioned in 1981 and was used to cool the cryopanel arrays for three hydrogen neutral beam injectors. Since then, new demands for liquid helium have arisen including: a fourth neutral beam injector, ten superco...

K. M. Schaubel G. J. Laughon G. L. Campbell A. R. Langhorn N. C. Stevens

1993-01-01

446

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

447

Improvement of Carbon Nanotubes using Cryogenic Treatment  

Microsoft Academic Search

Functional improvement of single-walled carbon nanotubes coated on polyimide Kapton HN was studied by means of cyclic cryogenic treatment. Immersing in liquid nitrogen at 77 K joining in heat annealing at 500 K induced the increase of D-G ratio and electrical conductivity in conjecture to the partial remedial junction with the coexisted stiction on surface. The coated thickness was deliberately

Dae-Weon Kim; Eui-Yun Jang; Seung-Min Lee; Wal-jun Kim; Jong-Hoon Lee; Jacob Kleiman

2007-01-01

448

Cost-Efficient Storage of Cryogens  

NASA Astrophysics Data System (ADS)

NASA's cryogenic infrastructure, which supports launch vehicle operations and propulsion testing, is reaching an age when major refurbishment is 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 various NASA field centers. Perlite powder has historically been the insulation material of choice for these applications, but new bulk-fill insulation materials, including glass bubbles and aerogel beads, have been shown to provide improved thermal and mechanical performance. Research was conducted on thermal performance to identify operational considerations and risks associated with using 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, granular physics, and insulation changeout). This research showed that more energy-efficient insulation solutions are possible for large-scale cryogenic storage tanks worldwide and summarized the operational requirements that should be considered for these applications.

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

2008-03-01

449

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

450

An Integrated 11GHz Cryogenic Downconverter  

Microsoft Academic Search

A cryogenic downconverter has been designed and built to demonstrate the integration of semiconducting and superconducting components in a complete subsystem cooled by a closed cycle Stirling cryocooler. The frequency selective receiver converts 11 GHz (X-band) signals to an IF of 1000 MHz using a high temperature superconducting (HTS) microstrip input filter with a 1% bandwidth, a silicon diode mixer

W A Phillips; D Jedamzik; K Lamacraft; S Zammattio; R B Greed; S J Hedges; P R Whitehead; B F Nicholson; T W Button; N McN Alford; N Peters; J Grier

1994-01-01

451

An integrated 11 GHz cryogenic downconverter  

Microsoft Academic Search

A cryogenic downconverter has been designed and built to demonstrate the integration of semiconducting and superconducting components in a complete subsystem cooled by a closed cycle Stirling cryocooler. The frequency selective receiver converts 11 GHz (X-band) signals to an IF of 1000 MHz using a high temperature superconducting (HTS) microstrip input filter with a 1% bandwidth, a silicon diode mixer

W. A. Phillips; D. Jedamzik; K. Lamacraft; S. Zammattio; R. B. Greed; S. J. Hedges; P. R. Whitehead; B. F. Nicholson; T. W. Button; P. A. Smith; N. M. Alford; N. Peters; J. Grier

1995-01-01

452

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

453

Reversible Resistive Switching in (La,Pr,Ca)MnO3; Cryogenic nonvolatile RAM  

NASA Astrophysics Data System (ADS)

Cryogenic-temperature electronics technologies are a practical promise for continuing demand for high performance electronics. By utilizing the unique hysteretic behavior of perovskite (La,Pr,Ca)MnO3 in the variation of temperature and applied electric fields, we have discovered that two electronically-distinct phases, with a huge difference in resistance (>10^5), can be repeatedly switched by applying various voltage pulses at cryogenic temperatures (e.g., 2 K), and the magnitude of resistance of each phase is highly stable with time. A multilevel memory effect for storing multiple bits was also found. We believe that the non-volatile cryo-PRAM utilizing our findings is an excellent candidate for memory devices for low-temperature electronic technologies such as quantum computers, Superconducting Rapid Single Flux Quantum (RSFQ) technology, low temperature detectors.

Yi, Hee Taek; Choi, Taekjib; Cheong, Sang-Wook

2010-03-01

454

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

455

The cryogenic cooling program in high-heat-load optics at the Advanced Photon Source  

SciTech Connect

This paper describes some of the aspects of the cryogenic optics program at the Advanced Photon Source (APS). A liquid-nitrogen-cooled, high-vacuum, double crystal monochromator is being fabricated at Argonne National Laboratory (ANL). A pumping system capable of delivering a variable flow rate of up to 10 gallons per minute of pressurized liquid nitrogen and removing 5 kilowatts of x-ray power is also being constructed. This specialized pumping system and monochromator will be used to test the viability of cryogenically cooled, high-heat-load synchrotron optics. It has been determined that heat transfer enhancement will be required for optics used with APS insertion devices. An analysis of a porous-matrix-enhanced monochromator crystal is presented. For the particular case investigated, a heat transfer enhancement factor of 5 to 6 was calculated.

Rogers, C.S.

1993-07-01

456

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

457

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

458

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

459

DC and 1/f noise characterization of cryogenically cooled pseudomorphic HEMT's  

NASA Astrophysics Data System (ADS)

Pseudomorphic (AIGaAs/InGaAs/GaAs) HEMT's have exhibited the best noise performance over the entire LF-to-microwave frequency range if compared to MESFET's and conventional GaAs HEMT's, due to either a reduced flicker noise, a lower G/R contribution and a smaller high-field diffusion noise. We have recently investigated the microwave (up to 18 GHz) noise properties of packaged pseudomorphic HEMT's from290K down to cryogenic temperature values. The current experimental work is aimed at extending such analysis to the LF noise range and at low temperatures. Cryogenic noise spectra (1 Hz to 100 KHz) and DC characteristics have therefore been recorded and the relevant observations on the device behavior are herewith reported.

Ferrante, G.; Principato, F.; Caddemi, A.; Donato, N.; Tuccari, G.

2002-05-01

460

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

461

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

462

DIII-D cryogenics control system status  

SciTech Connect

The DIII-D cryogenics system provides liquid helium for various auxiliary systems at the DIII-D tokamak facility. The system described here executes control and supervision of the cryogenics plant and associated load systems which include four neutral beam injectors, superconducting magnets, and an in-vessel tokamak cryocondensation pump. The recent addition of this divertor cryopump represented a major increase in the scope of the control system and greater need for reliable and automatic operation. The pump must be precooled, cooled and regenerated in a relatively short period of time under automatic control. Since the pump is located in the tokamak primary vacuum, coordination with the machine vacuum control system and consideration for the requirements of physics operations and vessel wall conditioning are required. A programmable logic controller is the central element in the cryogenics control system and exercises direct or supervisory control over the liquefier, gas management and loads. In the time since the control system was built during 1989, additions and improvements have been made to simplify operation and support upgrades. Cryogenics system capacity has been upgraded by the purchase of a new 150 {ell}/hr helium liquefier, a second 400 hp helium compressor and additional gas storage. The new liquefier incorporates a controller of its own which exchanges information with the cryogenics control system. This independent controller relieved the main system of liquefier process control tasks but necessitates much finer control of the system high and low pressures. The control system upgrades and automation are discussed with emphasis on the divertor cryocondensation pump control.

Campbell, G.L.; Harris, J.J.; Schaubel, K.M.

1993-09-01

463

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

464

Progress on GaAs cryogenic readout circuits for SISCAM  

NASA Astrophysics Data System (ADS)

We are developing cryogenic readout circuits for the array of superconducting tunneling junctions (STJs) at submillimeter wavelength SISCAM (Superconductive Imaging Submillimeter-wave CAMera). A current conceptual design of SISCAM will employ a direct hybrid array system just like CMOS image sensors widely used at optical and infrared wavelength. Because of relatively large impedance of the STJ fabricated by RIKEN (~10 M? in a dark condition), it requires readout preamplifier with low current noise. Therefore, it is not suitable for the STJ to use a readout system by Superconductive Quantum Interferences Devices as for Transition Edge Sensor. Instead, we selected capacitive transimpedance amplifier (CTIA) using a SONY n-type GaAs Junction Field Effect Transistor (JFET). However, the CTIA has not been used as the readout of the STJ. Therefore, we measured the photocurrent of the STJ by the CTIA with Silicon JFETs and by transimpedance amplifier (TIA), which is a conventional readout for the STJ, in the same bias condition, and confirmed both results are in good agreement. Additionally, we report development of readout integrated circuits with GaAs JFETs. In order to design the CTIA circuit with the GaAs JFETs, we fabricated the independent GaAs JFETs and matched pairs of them. We measured electrical characteristics of these GaAs JFETs at the cryogenic temperatures less than 4.2 K. We demonstrated performance of an operational amplifier fabricated with the GaAs JFETs measuring a differential amplifier with the dual GaAs JFET, and additionally estimate amplifier gain, offset voltage, and power consumption of the CTIA by the circuit simulation using the PSPICE. In consequence, the expected performance fulfills the requirements for the readout amplifier of the STJs except for the noise performance.

Nagata, H.; Kobayashi, J.; Matsuo, H.; Fujiwara, M.

2006-07-01

465

SiGe Technology for Military and Deep Space Cryogenic Power Electronics  

NASA Astrophysics Data System (ADS)

The increasing complexity of power electronic systems needed for advanced deep space missions and military electric-powered systems requires a new approach in materials and processes to realize circuitry and devices that operate efficiently at cryogenic temperatures. The n-type metal oxide semiconductor field effect transistor (n-MOSFET) is the building block for both digital and analog circuits. Silicon (Si) is a good material for fabricating power MOSFETs and electronic devices for operation down to 77 K, below which Si suffers from carrier freeze-out. Silicon carbide (SiC) is a wide-bandgap semiconductor material that is emerging in power electronic applications due to its superior properties, but SiC exhibits carrier freeze-out at temperatures higher than that of Si. Silicon gemanium (SiGe) heterostructure bipolar transistor (HBT) devices are promising candidates for low-temperature power applications. Presently, there is significant uncertainty in SiGe HBT characteristics at cryogenic operating conditions. Technology Applications, Inc. (TAI) has developed and evaluated SiGe strained-gate technology in the power metal oxide semiconductor field effect transistor (MOSFET) and complementary metal oxide semiconductor field effect transistor (CMOSFET) as active and logic devices to be operated in the range of 300 K to 40 K.

Nguyenphu, B.; Adebanjo, R.; Nieczkoski, S. J.; Yu, S.; Kapoor, V. J.; Sundaram, K. B.

2006-03-01

466

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

467

The Effects of Cryogenic Treatment on the Thermal Conductivity of GRCop-84  

Microsoft Academic Search

The mechanical properties of many materials have been enhanced via cryogenic treatment, which is a cold temperature process performed after traditional heat treatment. In this research the effect of cryogenic treatment on GRCop-84 was examined. Cryogenically and non-cryogenically treated samples were tested identically to determine whether cryogenic treatment has a significant affect on the thermal conductivity of GRCop-84. Optical and

Corey J. Isaak; Wayne Reitz

2007-01-01

468

Development of cryogen free Ic measurement system  

NASA Astrophysics Data System (ADS)

The increasing use of high-temperature superconducting (HTS) materials for advanced power applications has generated much interest in the acquisition of the voltage-current ( V- I) characteristic curve to measure the critical current ( Ic) of HTS tape. Cryogen free Ic measurement system for HTS wires or coils was designed and fabricated by using a GM-cryocooler and two HTS current leads. The sample cools conductively by 2nd stage of SRDK-408D cryocooler manufactured by Sumitomo Heavy Industries Ltd. (SHI). Each high temperature end of HTS current leads is thermally connected to 1st stage of the cryocooler and electrically disconnected. HTS tape samples cooled down by about 10 K. Ic measurements were conducted on a BSCCO-2212 tape, a BSCCO-2223 tape with joints and a BSCCO-2223 small coil under self-field. A description of cryogen free Ic measurement system design and results from a series of measurements will be presented.

Sohn, M. H.; Kim, S.; Sim, K. D.; Lee, E. Y.; Kim, H. M.; Park, H. Y.; Seong, K. C.; Kwon, Y. K.

2008-09-01

469

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

470

Hybrid cryogenic cooler for space flight applications.  

PubMed

The hybrid cryogenic cooler is an intermittent Joule-Thomson refrigerator with a precooler in the form of a passive radiator. The properties of the J-T expansion and the gas storage vessel are used to select fluids on the basis of available refrigeration per unit mass. Surface forces and container geometry are used to confine and control the liquid cryogen in a zero-gravity environment. The precooler and vaporized liquid are used to reduce parasitic thermal inputs to the point where most of the heat of vaporization is available for useful purposes. Modifications can be made to increase the efficiency or extend the temperature range. Ambient storage combined with efficient operation make the hybrid cooler attractive for space flight applications. PMID:20203860

Annable, R V

1978-09-01

471

Long term cryogenic storage facility systems study  

NASA Technical Reports Server (NTRS)

The Long Term Cryogenic Storage Facility Systems Study (LTCSFSS) is a Phase A study of a large capacity propellant depot for the space based, cryogenic orbital transfer vehicle. The study is being performed for Marshall Space Flight Center by General Dynamics Space Systems Division and has five principal objectives: (1) Definition of preliminary concept designs for four storage facility concepts; (2) Selection of preferred concepts through the application of trade studies to candidate propellant management system components; (3) Preparation of a conceptual design for an orbital storage facility; (4) Development of supporting research and technology requirements; and (5) Development of a test program to demonstrate facility performance. The initial study has been completed, and continuation activities are just getting under way to provide greater detail in key areas and accommodate changes in study guidelines and assumptions.

Schuster, John R.

1987-01-01

472

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

473

Characterization of titanium alloys for cryogenic applications  

NASA Astrophysics Data System (ADS)

Titanium alloys are employed in the design of superconducting magnet support systems for their high mechanical strength associated with their low thermal conductivity. But their use requires a careful attention to their crack tolerance at cryogenic temperature. Measurements have been performed on two extra low interstitial materials (Ti-5Al-2.5Sn ELI and Ti-6Al-4V ELI) with different thickness and manufacturing process. The investigation includes the tensile properties at room and liquid helium temperatures using smooth and notched samples. Moreover, the fracture toughness has been determined at 4.2 K using Compact Tension specimens. The microstructure of the different alloys and the various fracture surfaces have also been studied. After a detailed description of the experimental procedures, practical engineering characteristics are given and a comparison of the different titanium alloys is proposed for cryogenic applications. .

Reytier, M.; Kircher, F.; Levesy, B.

2002-05-01