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1

Survey of cryogenic semiconductor devices  

SciTech Connect

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

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

1996-04-01

2

Device for underwater cryogenic cutting  

SciTech Connect

An underwater cutting or penetrating device includes a source of liquid nitrogen for cooling a workpiece to a cryogenic temperature before impact by an explosively driven member. Attachment by magnet or clamp, and provision for confining the coolant by flexible gasket or boot are described.

Elkins, J.H.

1982-12-27

3

Cryogenic Magnetostrictive Materials and Devices  

NASA Astrophysics Data System (ADS)

Energen has patented KelvinAll™, the first material, to exhibit magnetostrictive properties from elevated temperatures to near absolute zero, opening up a new range of applications for magnetostrictive devices. Magnetostrictive materials change their shape in the presence of a magnetic field. This elongation is precise, predictable, reversible and repeatable thereby enabling practical electromechanical devices. KelvinAll has magnetostriction comparable to Terfenol-D at room temperature and its magnetostriction increases at cryogenic temperatures. Energen has developed and prototyped practical electromechanical devices using KelvinAll. These devices include tuners for superconducting radio frequency (SRF) cavities, components for magnetic refrigerators, flow control valves and precision translation stages some of which will be discussed in greater detail. Energen's KelvinAll products enhance performance, increase reliability and reduce development costs.

Joshi, C. H.; Mavanur, A.; Tai, C.-Y.; Han, Z.-X.; Rodenbush, A. J.; Wong, Y.

2004-06-01

4

Cryogenic vacuumm RF feedthrough device  

DOEpatents

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

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

2008-12-30

5

SiGe semiconductor devices for cryogenic power electronics - IV  

Microsoft Academic Search

We are developing power semiconductor devices based on SiGe, for operation at deep cryogenic temperatures. Cryogenic power devices and circuits are of interest for space missions to extremely cold environments. There are also potential applications on Earth in commercial, industrial, and defense systems that incorporate cryogenics or superconductivity. We report results for heterojunction bipolar transistors (HBTs). These are NPN-type with

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

2006-01-01

6

Device applications of cryogenic optical refrigeration  

NASA Astrophysics Data System (ADS)

With the coldest solid-state temperatures (?T <185K from 300K) achievable by optical refrigeration, it is now timely to apply this technology to cryogenic devices. Along with thermal management and pump absorption, this work addresses the most key engineering challenge of transferring cooling power to the payload while efficiently rejecting optical waste-heat fluorescence. We discuss our optimized design of such a thermal link, which shows excellent performance in optical rejection and thermal properties.

Melgaard, Seth D.; Seletskiy, Denis V.; Epstein, Richard I.; Alden, Jay V.; Sheik-Bahae, Mansoor

2014-02-01

7

Ge semiconductor devices for cryogenic power electronics: Part III  

Microsoft Academic Search

We have begun development of Ge power diodes and transistor for operation at cryogenic temperatures, down to ? 20 K (? -250°C), for use in spacecraft that will encounter low-temperature environments. Ge devices have advantages over Si devices for such deep cryogenic operation. Our initial development has yielded 10-A diodes with low forward voltage and reverse leakage, and reverse breakdown

R. R. Ward; W. J. Dawson; L. Zhu; R. K. Kirschmanf; O. Mueller; R. L. Patterson; J. E. Dickman; A. Hammoud

2003-01-01

8

Cryogenic Propellant Management Device: Conceptual Design Study  

NASA Technical Reports Server (NTRS)

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

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

2010-01-01

9

Ge semiconductor devices for cryogenic power electronics - II  

Microsoft Academic Search

We have begun investigation and development of cryogenic semiconductor power devices (diodes, bipolar transistors and field-effect transistors) based on germanium. The motivation is NASA's interest in electronics that can operate down to deep cryogenic temperatures (as low as -30-40 K) for exploration of the outer planets and other Solar System bodies that present cold environments as well as for future

R. R. Ward; W. J. Dawson; R. K. Kirschman; O. Mueller; R. L. Patterson; J. E. Dickman; A. Hammoud

2002-01-01

10

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

11

Ge semiconductor devices for cryogenic power electronics - II  

Microsoft Academic Search

We have begun investigation and development of cryogenic semiconductor power devices (diodes, bipolar transistors and field-effect transistors) based on germanium. The motivation is NASA's interest in electronics that can operate down to deep cryogenic temperatures (as low as {≈}30{-}40 K) for exploration of the outer planets and other Solar System bodies that present cold environments as well as for future

R. R. Ward; W. J. Dawson; R. K. Kirschman; O. Mueller; R. L. Patterson; J. E. Dickman; A. Hammoud

2002-01-01

12

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

13

Cryogenic Probe Station for On-Wafer Characterization of Electrical Devices Damon Russell,1, a)  

E-print Network

Cryogenic Probe Station for On-Wafer Characterization of Electrical Devices Damon Russell,1, a mobility transistors (HEMTs) remain the lowest noise temperature devices for use in cryogenic microwave such as silicon, and as a result the yield of low noise InP devices, especially at cryogenic tempera- tures

Weinreb, Sander

14

Charge dissipative dielectric for cryogenic devices  

NASA Technical Reports Server (NTRS)

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

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

2007-01-01

15

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

E-print Network

Thermal expansion of blood vessels in low cryogenic temperatures Part I: A new experimental device of biological material during cryopreservation processes, the current study focuses on thermal expansion device for thermal expansion measurements of blood vessels in typical conditions of vitrifi- cation

Rabin, Yoed

16

An overview on packaging of microwave electronic devices operating in a cryogenic environment  

NASA Astrophysics Data System (ADS)

Microwave cryogenic electronics design involves not only electrical, RF and electromagnetically considerations but also mechanical and assembly aspects. Details heavily influence the final device performances. Radio astronomical science often requires cooling down front end parts of the receivers in order to increase the system sensitivity. In this paper we will introduce the device working environment, crucial aspects of the housing, and we will describe a variety of possible solutions.

Cremonini, Andrea; Mariotti, Sergio; Roda, Juri

2012-10-01

17

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

18

Do-It-Yourself device for recovery of cryopreserved samples accidentally dropped into cryogenic storage tanks.  

PubMed

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 spaces (2). In laboratories, biological samples are often stored in cryovials or cryoboxes stacked in stainless steel racks within the Dewar tanks (1). 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 vials (3). 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. PMID:22617806

Mehta, Rohini; Baranova, Ancha; Birerdinc, Aybike

2012-01-01

19

BO12-xx header for SPIE use BiOS 2003, San Jose, CA, January Design and Construction of Experimental Device to Study Cryogen Droplet  

E-print Network

of Experimental Device to Study Cryogen Droplet Deposition and Heat Transfer Matthew D. Keller1,2 , Guillermo, Irvine, CA 92612 ABSTRACT Cryogen spray cooling (CSC) is used to pre-cool the epidermis during laser, essential to understand the mechanical and thermal interactions of cryogen droplets with the sprayed surface

Aguilar, Guillermo

20

Cryogenic refrigeration requirements for superconducting insertion devices in a light source  

SciTech Connect

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

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

2003-08-15

21

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

22

Liquid helium temperature irradiation effects on the operation of 0.7 ? ? ? ?m CMOS devices for cryogenic space applications  

Microsoft Academic Search

Introduction . The difficulties associated with predicting the radiation response of cryogenic circuitry based on room temperature irradiation studies has already been pointed out in the literature (1)-(2). Thus, radiation testing should preferably be performed at operating temperatures, which is not always practical (e.g., practical problems related to operating devices at liquid helium temperatures LHT). The basic reason for the

A. Mercha; Y. Creten; J. Putzeys; P. De Moor; C. Claeys; C. Van Hoof; E. Simoen; A. Mohammadzadeh; R. Nickson

23

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

PubMed

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

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

2014-09-01

24

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

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

25

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. PMID:16487503

Jimenez Rios, Jorge L.; Rabin, Yoed

2006-01-01

26

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

NASA Technical Reports Server (NTRS)

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

1987-01-01

27

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

28

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

NASA Technical Reports Server (NTRS)

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

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

2014-01-01

29

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

30

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

31

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. PMID:18958183

Jimenez Rios, Jorge L.; Rabin, Yoed

2008-01-01

32

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

33

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

34

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

SciTech Connect

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

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

2013-06-17

35

Cryogenic Safety This course will provide basic information concerning cryogens and  

E-print Network

Cryogenic Safety Training #12;This course will provide basic information concerning cryogens including cryogen, critical point, critical temperature, vacuum jacket, pressure relief device, dewar as the primary cryogens used at the NHMFL. n Explain the pressure hazards associated with contained cryogenic

McQuade, D. Tyler

36

A novel forficiform device for both temperature-compensating package for fiber Bragg gratings and cryogenic fiber Bragg grating temperature sensors  

Microsoft Academic Search

We present a novel forficiform device for both the temperature-compensating package for fiber Bragg gratings(FBGs) and cryogenic FBG temperature sensors. The wavelengths of the reflected light from 1550nm FBGs are measured in the temperature range from 77K to 353K .The temperature sensitivity of FBG sensors can be reduced by more than 10 times, reaching 0.001nm\\/K in the temperature range from

Gang Yu; Dan Cao

2005-01-01

37

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

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

38

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

NASA Technical Reports Server (NTRS)

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

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

1980-01-01

39

Cooling of superconducting devices by liquid storage and refrigeration unit  

DOEpatents

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

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

2013-08-20

40

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

NASA Astrophysics Data System (ADS)

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. BF2+ implant at a dose of 8×1013cm-2 does not amorphize silicon at room temperature. When implanted at -100°C, it forms a 30 - 35 nm thick amorphous layer. The cryogenic BF2+ 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+-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+BF2+, the cryogenic implants at -100°C enable removal of Ge preamorphization, and form more active n+-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

2012-11-01

41

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

42

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

43

Cryogenic characterization of Josephson junctions  

E-print Network

Cryogenic characterization is a crucial part of understanding the behavior of low-temperature quantum electronics. Reliable device testing provides the feedback to fabrication process development, facilitating the rapid ...

Brown, Keith Andrew

2006-01-01

44

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

45

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

46

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

47

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

48

Cryogenic Technology for Superconducting Accelerators  

NASA Astrophysics Data System (ADS)

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

Hosoyama, Kenji

2012-01-01

49

Guidance Document Cryogenic Liquids  

E-print Network

Guidance Document Cryogenic Liquids [This is a brief and general summary. Read the full MSDS for more details before handling.] Introduction: All cryogenic liquids are gases at normal temperature liquefies them. Cryogenic liquids are kept in the liquid state at very low temperatures. Cryogenic liquids

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

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

53

Cryogenic processing and recycling  

SciTech Connect

This article examines cryogenic processing and recycling of rubber and rubber products. The topics discussed include utilization of cryogenically recycled materials in the rubber industry, current status of the industry, economic benefit, performance advantage, environmental benefit, technology assessment, the future of cryogenic process and recycling.

Leyden, J.J.

1991-03-01

54

Cryogenic System Revised June 1994  

E-print Network

Chapter 9. Cryogenic System Revised June 1994 9.1. Introduction 9.2. Heat Loads and Refrigeration Duties -- 175 -- #12; 176 Cryogenic System #12; Cryogenic System 177 9.3. Two Phase Helium Cooling 9.4. The Refrigerator and Control #12; 178 Cryogenic System 9.5. Cryogen Delivery and Control 9.6. Three Cooling

Brookhaven National Laboratory - Experiment 821

55

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

56

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

57

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

58

Operation of power electronic converters at cryogenic temperatures for utility energy conditioning applications  

Microsoft Academic Search

The operation of power MOSFET devices at cryogenic temperatures has been shown to offer potential advantages in large conversion systems, due primarily to a major drop in on-resistance. This paper investigates the use of high frequency switch mode power electronics converters based on available commercial devices operating at cryogenic temperatures, particularly in relation to electricity supply applications. Efficiency, transient response

Alister I Gardiner; Stephen A Johnson; Ellery Schempp

1996-01-01

59

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

60

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

61

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

62

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

63

SNS Cryogenic Systems Commissioning  

NASA Astrophysics Data System (ADS)

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

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

2006-04-01

64

Advances in Cryogenic Principles  

NASA Astrophysics Data System (ADS)

During the past 50 years, the use of digital computers has significantly influenced the design and analysis of cryogenic systems. At the time when the first Cryogenic Engineering Conference was held, thermodynamic data were presented in graphical or tabular form (the "steam table" format), whereas thermodynamic data for cryogenic system design is computer generated today. The thermal analysis of cryogenic systems in the 1950s involved analytical solutions, graphical solutions, and relatively simple finite-difference approaches. These approaches have been supplanted by finite-element numerical programs which readily solve complicated thermal problems that could not be solved easily using the methods of the 1950s. In distillation column design, the use of the McCabe-Thiele graphical method for determination of the number of theoretical plates has been replaced by numerical methods that allow consideration of several different components in the feed and product streams.

Barron, R. F.

65

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

66

Cryogenic Transfer Line Chilldown  

Microsoft Academic Search

The transient behavior of a small-scale cryogenic transfer line was investigated during chilldown to cryogenic temperatures. The vacuum-jacketed apparatus consisted of a vertical tube followed by a near-horizontal tube. The tube diameter was 1 cm and the overall length was 4.4 m. The apparatus was equipped with view-ports in the near-horizontal section to allow visual observation of the flow patterns.

N. T. van Dresar; J. D. Siegwarth

2004-01-01

67

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

68

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

69

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

70

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

71

TPC magnet cryogenic system  

SciTech Connect

The Time Projection Chamber (TPC) magnet at LBL and its compensation solenoids are adiabatically stable superconducting solenoid magnets. The cryogenic system developed for the TPC magnet is discussed. This system uses forced two-phase tubular cooling with the two cryogens in the system. The liquid helium and liquid nitrogen are delivered through the cooled load by forced tubular flow. The only reservoirs of liquid cryogen exist in the control dewar (for liquid helium) and the conditioner dewar (for liquid nitrogen). The operation o these systems during virtually all phases of system operation are described. Photographs and diagrams of various system components are shown, and cryogenic system data are presented in the following sections: (1) heat leaks into the TPC coil package and the compensation solenoids; (2) heat leaks to various components of the TPC magnet cryogenics system besides the magnets and control dewar; (3) the control dewar and its relationship to the rest of the system; (4) the conditioner system and its role in cooling down the TPC magnet; (5) gas-cooled electrical leads and charging losses; and (6) a summation of the liquid helium and liquid nitrogen requirements for the TPC superconducting magnet system.

Green, M.A.; Burns, W.A.; Taylor, J.D.; Van Slyke, H.W.

1980-03-01

72

CRYOGENICS FOR FUSION  

SciTech Connect

Fusion of Hydrogen to produce energy is one of the technologies under study to meet the mankind raising need in energy and as a substitute to fossil fuels for the future. This technology is under investigation for more than 30 years already, with, for example, the former construction of the experimental reactors Tore Supra, DIII-D and JET. With the construction of ITER to start, the next step to 'fusion for energy' will be done. In these projects, an extensive use of cryogenic systems is requested. Air Liquide has been involved as cryogenic partner in most of former and presently constructed fusion reactors. In the present paper, a review of the cryogenic systems we delivered to Tore Supra, JET, IPR and KSTAR will be presented.

Dauguet, P.; Bonneton, M.; Fauve, E.; Bernhardt, J. M.; Beauvisage, J.; Andrieu, F. [Air Liquide Advanced Technology Division BP15, ZI Les Engenieres, 38360 Sassenage (France); Gistau-Baguer, G. M.; Boissin, J. C. [Consultants, Grenoble (France)

2008-03-16

73

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

74

Long hold time cryogens dewar  

SciTech Connect

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

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

1989-01-10

75

Cryogenic engineering and fusion power  

Microsoft Academic Search

In order to reduce the consumption of power for the magnets of a fusion power plant to acceptable proportions, it is necessary that fusion reactors must use either cryogenically cooled or superconducting coils. The cryogenic aspects of reactor design are discussed. It is found that the most difficult cryogenic engineering problems of fusion reactors are mainly those caused by the

C. E. Taylor

1974-01-01

76

Cryogenic Transfer Line Chilldown  

NASA Technical Reports Server (NTRS)

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

VanDresar, Neil T.; Siegwarth, James D.

2003-01-01

77

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

78

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

79

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

80

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

81

Vapor cooled current lead for cryogenic electrical equipment  

DOEpatents

Apparatus and method are provided for conducting electric current to cryogenic electrical equipment devices. A combination of inner and outer tubes together form a plurality of hollow composite tubes housed in a sheath. Top and bottom block mounting means are fitted to hold the composite tubes and are affixed to the ends of the sheath. This combination forms a current lead. The current lead is attached to a cryogenic device housing a fluid coolant which moves through the current lead, cooling the current lead as the fluid travels.

Vansant, James H. (Tracy, CA)

1983-01-01

82

Insulation design of cryogenic bushing for superconducting electric power applications  

NASA Astrophysics Data System (ADS)

Recently, the superconductivity projects to develop commercial superconducting devices for extra high voltage transmission lines have been undergoing in many countries. One of the critical components to be developed for high voltage superconducting devices, including superconducting transformers, cables, and fault current limiters, is a high voltage bushing, to supply high current to devices without insulating difficulties, that is designed for cryogenic environments. Unfortunately, suitable bushings for HTS equipment were not fully developed for some cryogenic insulation issues. Such high voltage bushings would need to provide electrical insulation capabilities from room temperature to cryogenic temperatures. In this paper, design factors of cryogenic bushings were discussed and test results of specimen were introduced in detail. First, the dielectric strength of three kinds of metals has been measured with uniform and non-uniform electrodes by withstand voltage of impulse and AC breakdown test in LN2. Second, puncture breakdown voltage of glass fiber reinforced plastics (GFRPs) plates has been analyzed with non-uniform electrodes. Finally, creepage discharge voltages were measured according to the configuration of non-uniform and uniform electrode on the FRP plate. From the test results, we obtained the basic design factors of extra high voltage condenser bushing, which could be used in cryogenic environment.

Koo, J. Y.; Lee, Y. J.; Shin, W. J.; Kim, Y. H.; Kim, J. T.; Lee, B. W.; Lee, S. H.

2013-01-01

83

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

84

Miniature cryogenic expansion turbines - A review  

NASA Astrophysics Data System (ADS)

Lord Rayleigh (1898) has first suggested the use of a turbine instead of a piston expander for the liquification of air. The development of expansion turbines is discussed, taking into account the first successful commercial application for cryogenic expansion turbines in Germany, Kapitza's turbine, work on much smaller turbines conducted in England, the development of a helium expansion turbine at the National Bureau of Standards, the development of small turboexpanders in Switzerland, the development of gas bearing expansion turbines, and the development of a small turboexpander similar to designs developed at the National Bureau of Standards. The reliability of cryogenic expansion turbines is discussed. It is found that applications for helium refrigerators and the demand for them would greatly increase if the reliability of these devices could be improved. Such a development would be crucial for the adoption of superconducting machinery by industry.

Sixsmith, H.

85

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

86

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

87

Cryogenic treatment of gas  

DOEpatents

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

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

2012-04-03

88

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

89

Safety and cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

The Langley 0.3-Meter Transonic Cryogenic Tunnel (0.3-m TCT) was placed in operation at NASA's Langley Research Center in 1973 as the world's first cryogenic pressure tunnel. The 0.3-m TCT can operate from ambient to cryogenic temperatures over an absolute pressure range from about 1 to 6 atmospheres. Three major test section concepts were developed and refined in this unique facility. The 0.3-m TCT is a leader in the development of various cryogenic pressure wind tunnel experimental techniques, instrumentation, control, model technology and safety standards. The safety experience gained is examined. During this period of advanced research, new operating techniques, training policies, and procedures had to be established. The paper deals with the Do's and Don'ts of cryogenic wind tunnel testing. Hazards and safety requirements which are unique to cryogenic testing are discussed. Highlights of experience and lessons learned with the 0.3-m TCT are reviewed.

Ray, Edward J.

1989-01-01

90

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.

91

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

92

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

93

Cryogenic storage vessel  

Microsoft Academic Search

McDonnell Douglas Corp.'s new cryogenic storage vessel design features internally-insulated tanks which may be used to store and transport liquefied gas at temperatures as low as -423°F, and store and transport fluids under high pressure or atmospheric pressure. The cargo tanks, which are integrally supported inside the cargo holds, feature a reliable liner-insulation system which can be installed in a

Lemons

1974-01-01

94

High performance cryogenic turboexpanders  

SciTech Connect

The use of turboexpanders for deep cryogenic temperatures has been constrained because of thermal efficiency limitations. This limited thermal efficiency was mostly due to mechanical constraints. Recent improvements in analytical techniques, bearing technology, and design features have made it possible to design and operate turboexpanders at more favorable conditions, such as of higher rotational speeds. Several turboexpander installations in helium and hydrogen processes have shown a significant improvement in plant performance over non-turboexpander options.

Agahi, R.R.; Ershaghi, B.; Lin, M.C. [Atlas Copco Rotoflow, Gardenia, CA (United States)

1996-12-31

95

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

96

Cryogenic Microwave Anisotropic Artificial Frank Trang  

E-print Network

Cryogenic Microwave Anisotropic Artificial Materials by Frank Trang B.S., University of California entitled: Cryogenic Microwave Anisotropic Artificial Materials written by Frank Trang has been approved.D., Electrical Engineering) Cryogenic Microwave Anisotropic Artificial Materials Thesis directed by Professor

Popovic, Zoya

97

Expandable Purge Chambers Would Protect Cryogenic Fittings  

NASA Technical Reports Server (NTRS)

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

Townsend, Ivan I., III

2004-01-01

98

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

99

The SNS Cryogenic Control System: Experiences in Collaboration  

SciTech Connect

The cryogenic system for the Spallation Neutron Source (SNS) is designed by Jefferson Laboratory (JLab) personnel and is based on the existing JLab facility. Our task is to use the JLab control system design [2] as much as practical while remaining consistent with SNS control system standards. Some aspects of the systems are very similar, including equipment to be controlled, the need for PID loops and automatic sequences,and the use of EPICS. There are differences in device naming, system hardware, and software tools. The cryogenic system is the first SNS system to be developed using SNS standards. This paper reports on our experiences in integrating the new and the old.

W.H. Strong; P.A. Gurd; J.D. Creel; B.S. Bevins

2001-11-01

100

Low-Heat-Leak Electrical Leads For Cryogenic Systems  

NASA Technical Reports Server (NTRS)

Electrical leads offering high electrical conductivity and low thermal conductivity developed for use in connecting electronic devices inside cryogenic systems to power supplies, signal-processing circuits, and other circuitry located in nearby warmer surroundings. Strip of superconductive leads on ceramic substrate, similar to ribbon cable, connects infrared detectors at temperature of liquid helium with warmer circuitry. Electrical leads bridging thermal gradient at boundary of cryogenic system designed both to minimize conduction of heat from surroundings through leads into system and to minimize resistive heating caused by electrical currents flowing in leads.

Wise, Stephanie A.; Hooker, Matthew W.

1994-01-01

101

Requirements for maintaining cryogenic propellants during planetary surface stays  

NASA Technical Reports Server (NTRS)

Potential impacts on the planetary surface system infrastructure resulting from the use of liquid hydrogen and oxygen propellants for a stage and half lander are discussed. Particular attention is given to techniques which can be incorporated into the surface infrastructure and/or the vehicle to minimize the impact resulting from the use of these cryogens. Methods offered for reducing cryogenic propellant boiloff include modification of the lander to accommodate boiloff, incorporation of passive thermal control devices to the lander, addition of active propellant management, and use of alternative propellants.

Riccio, Joseph R.; Schoenberg, Richard J.

1991-01-01

102

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

103

Cryogenic fluid management in space  

Microsoft Academic Search

Many future space based vehicles and satellites will require on orbit refuelling procedures. Cryogenic fluid management technology is being developed to assess the requirements of such procedures as well as to aid in the design and development of these vehicles. Cryogenic fluid management technology for this application could be divided into two areas of study, one is concerned with fluid

Basil N. Antar

1988-01-01

104

Cryogenic container compound suspension strap  

NASA Technical Reports Server (NTRS)

A support strap for use in a cryogenic storage vessel for supporting the inner shell from the outer shell with a minimum heat leak is presented. The compound suspension strap is made from a unidirectional fiberglass epoxy composite material with an ultimate tensile strength and fatigue strength which are approximately doubled when the material is cooled to a cryogenic temperature.

Vorreiter, J. W. (inventor)

1980-01-01

105

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

106

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

107

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

108

Cryogenic gas plant  

SciTech Connect

A process for separating substantially all of the C/sub 3/ and heavier components and a major portion of the C/sub 2/ component from a natural gas stream using a cryogenic process. The process uses a rectifying column in combination with a fractionating column to separate the C/sub 2/ and heavier components with the reflux for the rectifying column being supplied by compressing a small portion of the overheads and condensing it via heat exchange with the overheads stream.

Harryman, J. M.

1985-01-29

109

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

110

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

111

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

112

Biological Applications of Cryogenic Detectors  

SciTech Connect

High energy resolution and broadband efficiency are enabling the use of cryogenic detectors in biological research. Two areas where they have found initial application are X-ray absorption spectroscopy (XAS) and time-of-flight mass spectrometry (TOF-MS). In synchrotron-based fluorescence-detected XAS cryogenic detectors are used to examine the role of metals in biological systems by measuring their oxidation states and ligand symmetries. In time-of-flight mass spectrometry cryogenic detectors increase the sensitivity for biomolecule detection and identification for masses above {approx}50 kDa, and thus enable TOF-MS on large protein complexes or even entire viruses. More recently, cryogenic detectors have been proposed as optical sensors for fluorescence signals from biomarkers. We discuss the potential for cryogenic detectors in biological research, as well as the challenges the technology faces.

Friedrich, S

2003-12-03

113

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

114

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

115

Report on the first VLHC photon stop cryogenic design experiment  

SciTech Connect

As part of Fermilab's study of a Very Large Hadron Collider, 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.

Michael Geynisman et al.

2003-09-15

116

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

117

Cryogenic Transfer Line Chilldown  

NASA Astrophysics Data System (ADS)

The transient behavior of a small-scale cryogenic transfer line was investigated during chilldown to cryogenic temperatures. The vacuum-jacketed apparatus consisted of a vertical tube followed by a near-horizontal tube. The tube diameter was 1 cm and the overall length was 4.4 m. The apparatus was equipped with view-ports in the near-horizontal section to allow visual observation of the flow patterns. Wall temperatures were measured at various locations along the length of the transfer line. Each test was conducted at a constant liquid volumetric flowrate at the transfer line inlet until saturation temperatures were obtained throughout the system. Liquid flowrate was varied by more than two orders of magnitude and resulted in chilldown times ranging from a few minutes to several hours. An optimum flowrate exists that minimizes liquid consumption during the chilldown process. At higher flowrates, there is insufficient time for heat transfer from the liquid to the wall and inefficiencies result from the greater amount of incompletely vaporized liquid passing through the system. At lower flowrates, chilldown time and total ambient heat leak into the system increase, which raises liquid consumption. The experimental values of liquid consumption are compared to analytical estimates. At low flowrates, the data compares favorably to a minimum consumption model while at high flowrates the maximum consumption model overpredicts hydrogen consumption and underpredicts nitrogen consumption.

Van Dresar, N. T.; Siegwarth, J. D.

2004-06-01

118

Final version, May 2002 Cryogenics Assessment Report  

E-print Network

Final version, May 2002 1 Cryogenics Assessment Report M. J. Gouge, J. A. Demko and B. W. Mc (HTS) have long recognized the importance of cryogenics as an enabling technology. Cryogenic workshops-of-the-art in cryogenic components and estimated performance requirements when used with HTS electric power systems

119

On a cryogenic noble gas ion catcher  

E-print Network

In-situ purification of the gas used as stopping medium in a noble gas ion catcher by operating the device at low temperatures of 60 to 150 K was investigated. Alpha-decay recoil ions from a 223Ra source served as energetic probes. The combined ion survival and transport efficiencies for 219Rn ions saturated below about 90 K, reaching 28.7(17) % in helium, 22.1(13) % in neon, and 17.0(10) % in argon. These values may well reflect the charge exchange and stripping cross sections during the slowing down of the ions, and thus represent a fundamental upper limit for the efficiency of noble gas ion catcher devices. We suggest the cryogenic noble gas ion catcher as a technically simpler alternative to the ultra-high purity noble gas ion catcher operating at room temperature.

P. Dendooven; S. Purushothaman; K. Gloos

2005-10-20

120

On a cryogenic noble gas ion catcher  

NASA Astrophysics Data System (ADS)

In situ purification of the gas used as stopping medium in a noble gas ion catcher by operating the device at low temperatures of 60-150 K was investigated. Alpha-decay recoil ions from a 223Ra source served as energetic probes. The combined ion survival and transport efficiencies for 219Rn ions saturated below about 90 K, reaching 28.7(17)% in helium, 22.1(13)% in neon, and 17.0(10)% in argon. These values may well reflect the charge exchange and stripping cross-sections during the slowing down of the ions, and thus represent a fundamental upper limit for the efficiency of noble gas ion catcher devices. We suggest the cryogenic noble gas ion catcher as a technically simpler alternative to the ultra-high purity noble gas ion catcher operating at room temperature.

Dendooven, P.; Purushothaman, S.; Gloos, K.

2006-03-01

121

SR&DB Cryogenic Research & Development for Space Applications  

NASA Astrophysics Data System (ADS)

The Special Research and Development Bureau (SR&DB) for Cryogenic Technology of the B. Verkin Institute for Low Temperature Physics & Engineering was founded in 1971 and is located in Kharkov, Ukraine. Its primary focus has been in the area of applied r&d in the field of cryogenic technology for space applications. Within this field SR&DB has had many successful accomplishments, especially in the development of satellite based cryogenic cooling systems, mass spectrometer measurement devices, resistence thermometers, and cryogenically cooled optical systems. We have developed very advanced technology in the fields of fluids, heat transfer and hydrodynamics under micro-gravity conditions. Many of the SR&DB cryogenic products have been successfully implemented for former Soviet space applications, both near-earth and deep space. The SR&DB unique experience in many R&D areas can be and are being used for a new generation of space applications which have a requirement for planetary and deep-space missions. Systems we have developed have been proven to have a 5-year life in orbit. Recently we have focused much of our attention, as well, to the requirement low-weight and low-power systems which are mandatory requirements for outerspace missions. The funtionality of the exterior surfaces of a spacecraft are mainly dependent on the composition of its internally generated local atmosphere. In order to continually assess the content and concentration of components of this atmosphere we have developed space based mass spectrometric measuring devices. Devices which require such continual measurement are optical devices, emission receivers, solar cells, etc. A significant technology advance in the field of cryogenics is the application of cryoagents in systems of life support and spacecraft engine operation. We have studied and have an in-depth comprehension of unique phase-transition for these cryoagents such as oxygen, hydrogen, et al. under microgravity conditions. Currently SR&DB under contract to the National Space Agency of Ukraine has been developing an experimental apparatus for studying the continuous boiling off of cryogenic fluids under micro-gravity conditions.

Bondarenko, S. I.; Arkhipov, V. T.; Logvinenko, S. P.; Solodovnik, L. L.; Rusanov, K. V.; Shcherbakova, N. S.

122

Cryogenic Fluid Transfer for Exploration  

NASA Technical Reports Server (NTRS)

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

Chato, David J.

2008-01-01

123

Cryogenic Fluid Transfer for Exploration  

NASA Technical Reports Server (NTRS)

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

Chato, David J.

2007-01-01

124

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

125

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

126

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

127

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

128

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

129

Cryogenic nuclear gyroscope  

SciTech Connect

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

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

1980-09-30

130

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

131

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

132

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

133

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

134

R&D ERL: Cryogenic System  

SciTech Connect

The ERL cryogenic system will supply cooling to a super-conducting RF (SCRF) gun and the 5-cell super-conducting RF cavity system that need to be held cold at 2K. The engineering of the cavity cryomodules were carried out by AES in collaboration with BNL. The 2K superfluid bath is produced by pumping on the bath using a sub-atmospheric warm compression system. The cryogenic system makes use of mainly existing equipment relocated from other facilities: a 300W 4.5K coldbox, an 45 g/s screw compressor, a 3800 liter liquid helium storage dewar, a 170 m{sup 3} warm gas storage tank, and a 40,000 liter vertical low pressure liquid nitrogen storage dewar. An existing wet expander obtained from another facility has been added to increase the plant capacity. In order to deliver the required 3 to 4 bar helium to the cryomodules while using up stored liquid capacity at low pressure, a new subcooler will be installed to function as the capacity transfer device. A 2K to 4K recovery heat exchanger is also implemented for each cryomodule to recover refrigeration below 4K, thus maximizing 2K cooling capacity with the given sub-atmospheric pump. No 4K-300K refrigeration recovery is implemented at this time of the returning sub-atmospheric cold vapor, hence the 2K load appears as a liquefaction1 load on the cryogenic plant. A separate LN2 cooling loop supplies liquid nitrogen to the superconducting gun's cathode tip.

Than, R.

2010-01-01

135

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

136

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

137

Analysis of cryogenic calorimeter pulse shapes using a diffusion model  

NASA Astrophysics Data System (ADS)

Thermal pulses from cryogenic calorimeters are known to have shapes which are more complicated than simple models predict. The approach taken in this paper is to treat the propagation of heat in the device as diffusion in a continuous medium consisting of the absorber and thermal links. The model predictions will be discussed for microcalorimeters having tin absorbers, niobium-titanium thermal links, and neutron transmutation doped (NTD) germanium thermistors.

Deptuck, D.; Harrison, J. P.; Erhardt, L.

1996-02-01

138

Cryogenic Pressure Vessel workshop, LLNL, February 15, 2011, p. 1 Cryogenic Pressure Vessels  

E-print Network

Cryogenic Pressure Vessel workshop, LLNL, February 15, 2011, p. 1 Cryogenic Pressure Vessels This presentation does not contain any proprietary or confidential information #12;Cryogenic Pressure Vessel workshop, LLNL, February 15, 2011, p. 2 The cryogenic pressure vessel concept has evolved from

139

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

140

Overflow sensor for cryogenic-fluid vessels  

NASA Technical Reports Server (NTRS)

Overflow sensor for cryogenic fluid vessels has been designed by winding electrical resistance element on porous tubular coil form. Form is positioned in overflow vent of cryogenic fluid vessel where it can differentiate vapor from liquid at same temperature.

Tener, W. M.

1972-01-01

141

Resistance of Metallic Screens in a Cryogenic Flow  

NASA Astrophysics Data System (ADS)

The propellant behaviour in cryogenic upper stages tanks imposes challenging requirements on the design, especially for future upper stages designed for multiple restarts and long ballistic flight phases. The main challenge is the supply of the propellants to the feed system prior to the engine reignition. During the entire mission the engine requires a gaseous and bubble free liquid supply of propellant at the required thermodynamic conditions. The current research focus is to prepare the initial steps for the maturation of the Propellant Management Device (PMD) technology for cryogenic tank systems. Main components of such a PMD are metallic screens. The metallic screens are used as barrier for any gas bubbles within the fluid stream approaching the space craft engines. The screen characteristics are of fundamental importance for the PMD and feed system design. The paper presents a summary on available experimental screen data with regard to the flow resistance and gives a comparison with theoretical and empirical predictions found in literature. The lack on comparable data with regard to space craft applications and the need on further research with cryogenic flows is demonstrated. The DLR Institute of Space Systems is preparing various cryogenic tests to collect the desired information about the flow properties of such metallic screens. The planned test setup and the foreseen experiments will be presented.

Fischer, Alexander; Stief, Malte

142

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 Société 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

143

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

144

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

145

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

146

Developments and Cryogenic Measurements of an Optical  

E-print Network

Developments and Cryogenic Measurements of an Optical Transducer for the Gravitational Wave. Photograph by European Southern Observatory, 17 November 1999. #12;Developments and Cryogenic Measurements....................................... 4.7 Measurements of the resonator mechanical Q........................ 4.7.1 Cryogenic Run 1

147

Cryogenics and the human exploration of Mars  

Microsoft Academic Search

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

L. J. Salerno; P. Kittel

1999-01-01

148

Programmable 2-D Addressable Cryogenic Aperture Masks  

NASA Technical Reports Server (NTRS)

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

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

2004-01-01

149

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

150

A piezoelectric cryogenic heat switch  

NASA Astrophysics Data System (ADS)

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.

Jahromi, Amir E.; Sullivan, Dan F.

2014-06-01

151

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

152

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

153

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

154

Alternate approaches to cryogenic cooling  

NASA Astrophysics Data System (ADS)

Cryogenic cooling techniques for spaceborne infrared detectors are surveyed, and reason found to explore alternatives. An alternative class of cooling cycles is defined, and four practical cycles described. A general overview of operating efficiency for the whole class is developed. One of these cycles, the isobaric absorption cycle (Servel cycle), is explored in some detail.

Atkinson, W.; Devilliers, A.; Kappesser, R.

155

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

156

Operation of large cryogenic systems  

SciTech Connect

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

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

1985-06-01

157

Cryogenic separation of gaseous mixtures  

SciTech Connect

This patent describes a cryogenic separation process for recovering C{sub 2} hydrocarbons from a hydrocarbon feedstream comprising methane, ethene and ethane. It comprises introducing the hydrocarbon feedstream into a dephlegmation zone at cryogenic temperatures; dephlegmating the hydrocarbon feedstream into a primary methane-rich gas stream and a primary liquid condensate stream rich in C{sub 2} + hydrocarbon components and containing a minor amount of methane; passing the primary liquid condensate stream to a moderately low cryogenic temperature primary demethanizer unit and separating the primary liquid condensate stream into a C{sub 2} + liquid bottoms stream and intermediate methane-rich overhead vapor stream; and further separating the intermediate methane-rich overhead vapor stream from the moderately low cryogenic temperature primary demethanizer unit in an ultra-low temperature final demethanizer unit operating below about 175 psia to recover a first liquid ethene-rich hydrocarbon product stream and a final demethanizer ultra-low temperature vapor stream; whereby total energy requirements for refrigeration to separate the C{sub 2} + hydrocarbon from the C{sub 1} and lighter components are low.

McCue, R.H. Jr.

1991-07-30

158

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

159

Foam shell cryogenic ICF target  

DOEpatents

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

160

Ames Research Center cryogenics program  

NASA Technical Reports Server (NTRS)

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 orbital disconnect, a pulse tube refrigerator, a dilution refrigerator, and an adiabatic demagnetization cooler.

Kittel, Peter

1987-01-01

161

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

162

JWST's cryogenic position metrology system  

NASA Astrophysics Data System (ADS)

The James Webb Space Telescope will undergo a full system test in the cryogenic vacuum chamber A at the Johnson Spaceflight Center in order to verify the overall performance of the combined telescope and instrument suite. This will be the largest and most extensive cryogenic test ever undertaken. Early in the test system development, it was determined that precise position measurements of the overall hardware would enhance the test results. Various concepts were considered before selecting photogrammetry for this metrology. Photogrammetry has been used in space systems for decades, however cryogenic use combined with the size and the optical/thermal sensitivity of JWST creates a unique set of implementation challenges. This paper provides an overview of the JWST photogrammetric system and mitigation strategies for three key engineering design challenges: 1) the thermal design of the viewing windows to prevent excessive heat leak and stray light to the test article 2) cost effective motors and mechanisms to provide the angle diversity required, and 3) camera-flash life and reliability sufficient for inaccessible use during the number and duration of the cryogenic tests.

Whitman, Tony L.; Hammond, Randolph P.; Orndorff, Joe; Hope, Stephen; Smee, Stephen A.; Scorse, Thomas; Havey, Keith A.

2012-09-01

163

Ilc Cryogenic Systems Reference Design  

NASA Astrophysics Data System (ADS)

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

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

2008-03-01

164

A Magnetically Coupled Cryogenic Pump  

NASA Technical Reports Server (NTRS)

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

Hatfield, Walter; Jumper, Kevin

2011-01-01

165

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

NASA Astrophysics Data System (ADS)

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.

1990-08-01

166

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

167

Relaxation phenomena in cryogenic electrolytes  

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

168

Advanced Reusable Foam Cryogenic Insulation  

NASA Technical Reports Server (NTRS)

Lightweight, reusable cryogenic containers reduce costs of operation of advanced hypersonic airplanes and space launch vehicles. Specimens demonstrated in temperature range of negative 420 to positive 400 degrees F (negative 251 to positive 204 degrees C). Prototype reusable cryogenic foam insulation developed. Consists of two discrete layers of closed-cell polymethacrylimide foam of density 6.9 lb/ft to the 3rd power (111 kg/m to the 3rd power) bonded together with epoxy adhesive. Additionally reinforced with 0.003-in. (0.08-mm)-thick layer of fiberglass cloth. Wrapped with precut and preformed vapor-barrier cover. Such containers useful on Earth in laboratories, factories, and transportation systems.

Taylor, Allan H.; Mcauliffe, P. S.; Sparks, L. L.

1990-01-01

169

Electromagnetic dampers for cryogenic applications  

NASA Technical Reports Server (NTRS)

Cryogenic turbomachinery of the type used to pump high-pressure liquid hydrogen at -423 F and liquid oxygen at -297 F to the main engines of the Space Shuttle are subjected to lateral rotor vibrations from unbalance forces and transient loads. Conventional dampers which utilize viscous fluids such as lubricating oil cannot be used in turbopumps because the bearing components are filled with either liquid hydrogen or liquid oxygen, which have viscosity comparable to air and, therefore, are not effective in viscous dampers. Electromagentic dampers are currently being explored as a means of providing damping in cryogenic turbopumps because their damping effectiveness increases as temperature decreases and because they are compatible with the liquid hydrogen or liquid oxygen in the turbopumps.

Brown, Gerald V.; Dirusso, Eliseo

1988-01-01

170

Cryogenics for the Superconducting Module Test Facility  

NASA Astrophysics Data System (ADS)

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.

2006-04-01

171

Cryogenics and the human exploration of Mars.  

NASA Astrophysics Data System (ADS)

Current studies within NASA involve extending the human exploration of space from low earth orbit into the solar system, with the first human exploration of Mars proposed in 2014. The key cryogenic technology areas to be addressed in human Mars missions are long-term propellant storage, cryogenic refrigeration, cryogenic liquefaction, and zero gravity fluid management. Passive technologies such as advanced multilayer insulation (MLI) concepts, vapor-cooled shields (VCS), and catalytic converters will be combined with the development of active coolers (cryogenic refrigerators). The integration of passive and active technologies will form a hybrid system optimized to minimize the launch mass while preserving the cryogenic propellants. This paper presents a brief overview of the proposed Mars reference mission and the concomitant cryogenic fluid management technology, focusing on active cooling technology.

Salerno, L. J.; Kittel, P.

1999-04-01

172

Surface tension confined liquid cryogen cooler  

SciTech Connect

A cryogenic cooler is described for use in craft such as launch, orbital and space vehicles subject to changes in orientation and conditions of vibration and weightlessness comprising: an insulated tank; a porous open celled sponge-like material disposed substantially throughout the contained volume of the insulated tank; a cryogenic fluid disposed within the sponge-like material; a cooling finger immersed in the cryogenic fluid, the finger extending from inside the insulated tank externally to an outside source such as an instrument detector for the purpose of transmitting heat from the outside source into the cryogenic fluid; means for filling the insulated tank with cryogenic fluid; and means for venting vaporized cryogenic fluid from the insulated tank.

Castles, S.H.; Schein, M.E.

1989-04-18

173

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

174

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

175

Usaf Space Sensing Cryogenic Considerations  

NASA Astrophysics Data System (ADS)

Infrared (IR) space sensing missions of the future depend upon low mass components and highly capable imaging technologies. Limitations in visible imaging due to the earth's shadow drive the use of IR surveillance methods for a wide variety of applications for Intelligence, Surveillance, and Reconnaissance (ISR), Ballistic Missile Defense (BMD) applications, and almost certainly in Space Situational Awareness (SSA) and Operationally Responsive Space (ORS) missions. Utilization of IR sensors greatly expands and improves mission capabilities including target and target behavioral discrimination. Background IR emissions and electronic noise that is inherently present in Focal Plane Arrays (FPAs) and surveillance optics bench designs prevents their use unless they are cooled to cryogenic temperatures. This paper describes the role of cryogenic coolers as an enabling technology for generic ISR and BMD missions and provides ISR and BMD mission and requirement planners with a brief glimpse of this critical technology implementation potential. The interaction between cryogenic refrigeration component performance and the IR sensor optics and FPA can be seen as not only mission enabling but also as mission performance enhancing when the refrigeration system is considered as part of an overall optimization problem.

Roush, F.

2010-04-01

176

Cryogenic fluid management in space  

NASA Astrophysics Data System (ADS)

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

Antar, Basil N.

1988-12-01

177

Cryogenic microwave anisotropic artificial materials  

NASA Astrophysics Data System (ADS)

This thesis addresses analysis and design of a cryogenic microwave anisotropic wave guiding structure that isolates an antenna from external incident fields from specific directions. The focus of this research is to design and optimize the radome's constituent material parameters for maximizing the isolation between an interior receiver antenna and an exterior transmitter without significantly disturbing the transmitter antenna far field characteristics. The design, characterization, and optimization of high-temperature superconducting metamaterials constitutive parameters are developed in this work at X-band frequencies. A calibrated characterization method for testing arrays of split-ring resonators at cryogenic temperature inside a TE10 waveguide was developed and used to back-out anisotropic equivalent material parameters. The artificial material elements (YBCO split-ring resonators on MgO substrate) are optimized to improve the narrowband performance of the metamaterial radome with respect to maximizing isolation and minimizing shadowing, defined as a reduction of the transmitted power external to the radome. The optimized radome is fabricated and characterized in a parallel plate waveguide in a cryogenic environment to demonstrate the degree of isolation and shadowing resulting from its presence. At 11.12 GHz, measurements show that the HTS metamaterial radome achieved an isolation of 10.5 dB and the external power at 100 mm behind the radome is reduced by 1.9 dB. This work demonstrates the feasibility of fabricating a structure that provides good isolation between two antennas and low disturbance of the transmitter's fields.

Trang, Frank

178

ZERODUR TAILORED for cryogenic application  

NASA Astrophysics Data System (ADS)

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

Jedamzik, R.; Westerhoff, T.

2014-07-01

179

Investigation of cryogenic rupture disc design  

NASA Technical Reports Server (NTRS)

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

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

1973-01-01

180

Properties of cryogenically worked metals. [stainless steels  

NASA Technical Reports Server (NTRS)

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

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

1975-01-01

181

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.

182

CRYOGENIC FLUID JETS AND MIXING LAYERS IN TRANSCRITICAL AND SUPERCRITICAL  

E-print Network

CRYOGENIC FLUID JETS AND MIXING LAYERS IN TRANSCRITICAL AND SUPERCRITICAL ENVIRONMENTS NAN ZONG modeling and numerical simulation of cryogenic fluid injection and mixing in transcritical- layer instability, volume dilatation, and property variations, dictating the evolution of cryogenic jets

Yang, Vigor

183

Cryogenic Particle Detectors in Search for Dark Matter  

E-print Network

Cryogenic Particle Detectors in Search for Dark Matter Panofsky Prize presentation American;Panofsky Prize Talk - Cryogenic Dark Matter Detectors Page Blas Cabrera - Stanford University Original #12;Panofsky Prize Talk - Cryogenic Dark Matter Detectors Page Blas Cabrera - Stanford University TES

California at Berkeley, University of

184

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2010 CFR

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

2010-10-01

185

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2012 CFR

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

2012-10-01

186

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2011 CFR

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

2011-10-01

187

49 CFR 173.319 - Cryogenic liquids in tank cars.  

Code of Federal Regulations, 2013 CFR

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

2013-10-01

188

Cryogenic transistor measurement and modeling for engineering applications  

NASA Astrophysics Data System (ADS)

This article deals with the methodology of an electronic system design at liquid-helium temperatures. This technique includes the active device selection, characterization and simulation. Based on certain engineering criteria one commercial reference of SiGe heterojunction bipolar transistors is selected. Then, the technique of device characterization and measurement is considered. Typical output characteristics are given for this reference. All the tested devices of this reference are classified into three groups according to the presence of different low-temperature phenomena. An accurate and easy-to-use neural network model based on their experimental DC characteristics is proposed. This model is implemented in Agilent ADS Software, and the simulation results are compared with measurements in the course of the cryogenic amplifier design.

Goryachev, Maxim; Galliou, Serge; Abbé, Philippe

2010-06-01

189

Effects of electrostatic discharge on three cryogenic temperature sensor models  

NASA Astrophysics Data System (ADS)

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

Courts, S. Scott; Mott, Thomas B.

2014-01-01

190

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

191

Developing Low-Noise GaAs JFETs For Cryogenic Operation  

NASA Technical Reports Server (NTRS)

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

Cunningham, Thomas J.

1995-01-01

192

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

193

Cryogenic filter wheel design for an infrared instrument  

NASA Astrophysics Data System (ADS)

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

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

2014-09-01

194

Issues of Long-Term Cryogenic Propellant Storage in Microgravity  

NASA Technical Reports Server (NTRS)

Modern multi-layer insulation (MLI) allows to sharply reduce the heat leak into cryogenic propellant storage tanks through the tank surface and, as a consequence, significantly extend the storage duration. In this situation the MLI penetrations, such as support struts, feed lines, etc., become one of the most significant challenges of the tanks heat management. This problem is especially acute for liquid hydrogen (LH2) storage, since currently no efficient cryocoolers exist that operate at very low LH2 temperatures (20K). Even small heat leaks under microgravity conditions and over the period of many months give rise to a complex slowly-developing, large-scale spatiotemporal physical phenomena in a multi-phase liquid-vapor mixture. These phenomena are not well-understood nor can be easily controlled. They can be of a potentially hazardous nature for long-term on-orbital cryogenic torage, propellant loading, tank chilldown, engine restart, and other in-space cryogenic fluid management operations. To support the engineering design solutions that would mitigate these effects a detailed physics-based analysis of heat transfer, vapor bubble formation, growth, motion, coalescence and collapse is required in the presence of stirring jets of different configurations and passive cooling devices such as MLI, thermodynamic vent system, and vapor-cooled shield. To develop physics-based models and correlations reliable for microgravity conditions and long-time scales there is a need for new fundamental data to be collected from on-orbit cryogenic storage experiments. Our report discusses some of these physical phenomena and the design requirements and future studies necessary for their mitigation. Special attention is payed to the phenomena occurring near MLI penetrations.

Muratov, C. B.; Osipov, Viatcheslav V.; Smelyanskiy, Vadim N.

2011-01-01

195

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

196

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

197

Cryogenic Cermic Multilayer Capacitors for Power Electronics  

NASA Astrophysics Data System (ADS)

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 ˜ 1000-4000) barium titanate doped to yield and X7R temperature dependence (±15% change in capacitance from -55°C to 125°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.

2006-03-01

198

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

199

Continuous-Reading Cryogen Level Sensor  

NASA Technical Reports Server (NTRS)

Two pressure transducers used in system for measuring amount of cryogenic liquid in tank. System provides continuous measurements accurate within 0.03 percent. Sensors determine pressure in liquid and vapor in tank. Microprocessor uses pressure difference to compute mass of cryogenic liquid in tank. New system allows continuous sensing; unaffected by localized variations in composition and density as are capacitance-sensing schemes.

Barone, F. E.; Fox, E.; Macumber, S.

1984-01-01

200

Cryogenic magnetic force microscope M. Rosemana)  

E-print Network

Cryogenic magnetic force microscope M. Rosemana) and P. Gru¨tter Centre for the Physics for publication 27 June 2000 We describe our cryogenic magnetic force microscope, operating between 4.2 and 300 K. As an effective means of vibration isolation, we suspend the microscope from a soft bellows which attenuates

Grütter, Peter

201

Neutron detection with cryogenics and semiconductors  

Microsoft Academic Search

The common methods of neutron detection are reviewed with special attention paid to the application of cryogenics and semiconductors to the problem. The authors' work with LiF- and boron-based cryogenic instruments is described as well as the use of CdTe and HgI2 for direct detection of neutrons.

Zane W. Bell; D. A. Carpenter; S. S. Cristy; V. E. Lamberti; Arnold Burger; Brian F. Woodfield; Thomas Niedermayr; I. Dragos Hau; Simon E. Labov; Stephan Friedrich; W. Geoffrey West; Kenneth R. Pohl; Lodewijk van den Berg

2005-01-01

202

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

203

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

204

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

205

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

206

Surface tension confined liquid cryogen cooler  

Microsoft Academic Search

A cryogenic cooler is provided for use in craft such as launch, orbital, and space vehicles subject to substantial vibration, changes in orientation, and weightlessness. The cooler contains a small pore, large free volume, low density material to restrain a cryogen through surface tension effects during launch and zero-g operations and maintains instrumentation within the temperature range of 10 to

Stephen H. Castles; Michael E. Schein

1989-01-01

207

Self-Sealing Cryogenic Fitting  

NASA Technical Reports Server (NTRS)

Self-sealing fitting for cryogenic tubes remains free of leakage from room temperature to liquid-helium temperature even at internal pressure as high as 2.7 MPa. Fitting comprises parts made of materials with different coefficients of thermal expansion to prevent leakage gaps from forming as temperature decreases. Consists of coupling nut, two flared tube ends, and flared O-ring spacer. Spacer contracts more than tube ends do as temperature decreases. This greater contraction seals tube ends more tightly, preventing leakage.

Jia, Lin Xiang; Chow, Wen Lung; Moslemian, Davood; Lin, Gary; Melton, Greg

1994-01-01

208

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

209

Applications of the second law of thermodynamics to cryogenics - A review  

NASA Astrophysics Data System (ADS)

Benefits derived from application of the second law of thermodynamics to cryogenics are reviewed. Early applications of second law analysis resulted in using staged or cascaded systems and work recovery devices to reduce the power requirements for air and helium liquefaction systems. More recent second law studies, based on minimization of irreversible entropy production and exergy losses, are providing a greater insight into the influence of irreversible losses on the power expended to achieve cryogenic temperature refrigeration. These studies show the significant penalty in power attributed to irreversible system losses, and also indicate some design and operational procedures that can minimize this power penalty. Some future energy systems, such as magnetohydrodynamic power, superconducting magnet energy storage, fusion power, magnetic levitated transportation, LNG, and liquid hydrogen storage and transportation, involve cryogenic technology. These systems will benefit from consideration of the second law in their design and performance analysis.

Ahern, J. E.

1980-09-01

210

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

211

Cryogenic direct current superconducting quantum interference device readout circuit  

E-print Network

SQUID readout circuit, which can be operated at liquid helium temperatures. Although room can be used as amplifier, phase-sensitive detector and integrator. The power dissipation circuit as a null detector of mag- netic flux.1 Operating a SQUID in this so-called flux-locked loop

Le Roy, Robert J.

212

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

213

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

214

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

215

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

216

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

217

Challenges for Cryogenics at Iter  

NASA Astrophysics Data System (ADS)

Nuclear fusion of light nuclei is a promising option to provide clean, safe and cost competitive energy in the future. The ITER experimental reactor being designed by seven partners representing more than half of the world population will be assembled at Cadarache, South of France in the next decade. It is a thermonuclear fusion Tokamak that requires high magnetic fields to confine and stabilize the plasma. Cryogenic technology is extensively employed to achieve low-temperature conditions for the magnet and vacuum pumping systems. Efficient and reliable continuous operation shall be achieved despite unprecedented dynamic heat loads due to magnetic field variations and neutron production from the fusion reaction. Constraints and requirements of the largest superconducting Tokamak machine have been analyzed. Safety and technical risks have been initially assessed and proposals to mitigate the consequences analyzed. Industrial standards and components are being investigated to anticipate the requirements of reliable and efficient large scale energy production. After describing the basic features of ITER and its cryogenic system, we shall present the key design requirements, improvements, optimizations and challenges.

Serio, L.

2010-04-01

218

Superconducting RF Systems and Cryogenics  

SciTech Connect

The subgroup on Supercondcuting RF Systems and Cryogenics was assigned the following tasks: (1) provide acceptable design recommendations for the accelerating structures and related RF and Cryogenics systems based on the parameters established by High Energy and Nuclear Physics needs (namely a final energy of 2.5 and 8 GeV at the end of the first and second stage, respectively, and the ability of accelerating simultaneously the 200{micro}A Nuclear Physics beam and the three bunches for High Energy Physics). (2) estimate the cost of such systems based on realistic, present day technology, with some assessment of future costs as technology and cavity manufacturing processes will improve. These tasks were carried out for the case of the original design which includes two racetracks of similar structure and with different energies, as well as for the more recent design of Amaldi and Coignet which is capable of reaching a center of mass energy of 15 GeV (alternate design). Design and cost estimates were done for a few cases of possible achievable gradients.

C. Benvenuti; P. Bernard; E. Chiaveri; E. Haebel; H. Lengeler; M. Minestrini; Joseph Bisognano; Isidoro Campisi; Christoph Leemann; R. Boni; U. Gambardella; G. Modestino; B Spataro; F. Tazzioli; H. Piel

1987-12-01

219

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

220

Experimental measurements and noise analysis of a cryogenic radiometer  

NASA Astrophysics Data System (ADS)

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

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

2014-07-01

221

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

222

A cryogenic receiver for EPR R. Narkowicz a,  

E-print Network

A cryogenic receiver for EPR R. Narkowicz a, , H. Ogata b , E. Reijerse b , D. Suter a a Department: Cryogenic receiver Planar microresonators Signal-to-noise ratio Sensitivity a b s t r a c t Cryogenic probes capable of cryogenic operation. Compared to room temperature operation, it reduces the noise by a factor

Suter, Dieter

223

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

224

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

225

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

226

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

227

Structural damping studies at cryogenic temperatures  

NASA Technical Reports Server (NTRS)

Results of an engineering study to measure changes in structural damping properties of two cryogenic wind tunnel model systems and two metallic test specimens at cryogenic temperatures are presented. Data are presented which indicate overall, a trend toward reduced structural damping at cryogenic temperatures (-250 degrees F) when compared with room temperature damping properties. The study was focused on structures and materials used for model systems tested in the National Transonic Facility (NTF). The study suggests that the significant reductions in damping at extremely cold temperatures are most likely associated with changes in mechanical joint compliance damping rather than changes in material (solid) damping.

Young, Clarence P., Jr.; Buehrle, Ralph D.

1994-01-01

228

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

229

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

230

External heat loads on a cryogenic radiator  

NASA Astrophysics Data System (ADS)

Cryogenic radiators are necessary for instruments on earth-orbiting spacecraft for applications in the infrared spectral regions to maintain operating temperatures of 75-100 K. The radiator size can be greatly affected by parasitic heat loads. This paper presents the results of a study which calculated the heat fluxes from solar arrays, masts, and other external appendages to a cryogenic radiator in a synchronous orbit. The analyses showed that care must be taken in the location of spacecraft components that may see a cryogenic radiator. Without proper shielding heat fluxes can easily exceed the radiators cooling capability.

Wedel, R. K.; Zingale, T.

1991-06-01

231

Design of propellant acquisition systems for advanced cryogenic space propulsion systems  

NASA Technical Reports Server (NTRS)

This paper presents results of work conducted to expand the technology base and evolve practical propellant surface tension acquisition system designs for future cryogenic space vehicles. Surface tension screen device channel flow analysis and supporting tests showed that reasonable mesh sizes could provide the required retention performance. Integrated subsystem studies and development showed that practical and effective screen surface tension acquisition devices could be designed for typical applications, but that other interfacing feed subsystems are often constrained by the design of the particular acquisition device. These constraints may dominate the total feed system performance.

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

1973-01-01

232

Designing insulation for cryogenic ducts  

NASA Astrophysics Data System (ADS)

It is pointed out that the great temperature difference between the outside of a cryogenic duct and the liquified gas it carries can cause a high heat input unless blocked by a high thermal resistance. High thermal resistance for lines needing maximum insulation is provided by metal vacuum jackets. Low-density foam is satisfactory in cases in which higher heat input can be tolerated. Attention is given to the heat transfer through a duct vacuum jacket, the calculation of heat input and the exterior surface's steady-state temperature for various thicknesses of insulation, the calculation of the heat transfer through gimbal jackets, and design specifications regarding the allowable pressure rise in the jacket's annular space.

Love, C. C.

1984-03-01

233

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

234

The Nuclear Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

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

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

2014-01-01

235

The Nuclear Cryogenic Propulsion Stage  

NASA Technical Reports Server (NTRS)

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

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

2014-01-01

236

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

237

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.

238

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

239

Evaluation of two designs for cryogenic insulation  

NASA Technical Reports Server (NTRS)

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

Getty, R. C.

1970-01-01

240

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

241

Advances in cryogenic engineering. Volume 26 - Materials  

SciTech Connect

Materials resource considerations for cryogenic engineering are discussed along with Nb-Ti alloy superconductors, the magnetic character of austenitic stainless steels, the alteration of the superconducting properties of A15 compounds and elementary composite superconductors by nonhydrostatic elastic strain, cryogenic processing, and international standards for cryogenic polymers and composites. A review is presented of antifriction materials and design for cryogenic environments. Other subjects considered are related to metals and alloys, welding, composites, in situ processed superconductors, A15 superconductors, Nb-Ti and aluminum-stabilized superconductors, strain effects in superconductors, the characterization of superconducting systems, and stability and training in superconductors. Attention is given to the propagation of normal zones in thermally insulated superconductors, stability measurements of a large Nb/sub 3/Sn force-cooled conductor, and the ac losses and stabilization of Nb/sub 3/Sn superconducting tapes.

Clark, A.F.; Reed, R.P.

1980-01-01

242

The Fast Alternative Cryogenic Experiment Testbed  

NASA Technical Reports Server (NTRS)

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

Nash, Alfred; Holmes, Warren

2000-01-01

243

Optimum temperature staging of cryogenic refrigeration system  

NASA Astrophysics Data System (ADS)

Optimum temperature staging is investigated to minimize entropy generation in a multi-stage cryogenic refrigeration cycle. It is found that the best intermediate temperature distribution is to have the same high to low temperature ratio at each stage of the system. As an example, the result is applied to the design of a cryogenic cascade thermoelectric cooler to find the optimum size distribution of each stage.

Jeong, S.; Smith, J. L.

244

Creep of pure aluminum at cryogenic temperatures  

E-print Network

Conducted on OFHC Copper . B. Equipment Used in Successful Long-term Creep Testing. . . C. Creep Mechanisms at Cryogenic Temperatures. . . . . . . . . . 8 8 11 III PRIMARY RESEARCH OBJECTIVE . . 14 IV EXPERIMENTAL SETUP AND PROCEDURES . . 15 A. Load... aluminum and NbTi. 2 Constant load creep curve showing three distinct regions. 3 Creep curves for OPHC copper taken over 200 hours. 10 4 Photograph of creep frame used in cryogenic creep tests. . . . . . . . . 5 Photograph of top of creep frame showing...

McDonald, Lacy Clark

2012-06-07

245

Adhesive bond cryogenic lens cell margin of safety test  

NASA Astrophysics Data System (ADS)

The Near Infrared Camera (NIRCam) instrument for NASA's James Webb Space Telescope (JWST) has an optical prescription which employs four triplet lens cells. The instrument will operate at 35K after experiencing launch loads at approximately 295K and the optic mounts must accommodate all associated thermal and mechanical stresses, plus maintain an exceptional wavefront during operation. Lockheed Martin Space Systems Company (LMSSC) was tasked to design and qualify the bonded cryogenic lens assemblies for room temperature launch, cryogenic operation, and thermal survival (25K) environments. The triplet lens cell designs incorporated coefficient of thermal expansion (CTE) matched bond pad-to-optic interfaces, in concert with flexures to minimize bond line stress and induced optical distortion. A companion finite element study determined the bonded system's sensitivity to bond line thickness, adhesive modulus, and adhesive CTE. The design team used those results to tailor the bond line parameters, minimizing stress transmitted into the optic. The challenge for the Margin of Safety (MOS) team was to design and execute a test that verified all bond pad/adhesive/ optic substrate combinations had the required safety factor to generate confidence in a very low probability optic bond failure during the warm launch and cryogenic survival conditions. Because the survival temperature was specified to be 25K, merely dropping the test temperature to verify margin was not possible. A shear/moment loading device was conceived that simultaneously loaded the test coupons at 25K to verify margin. This paper covers the design/fab/SEM measurement/thermal conditioning of the MOS test articles, the thermal/structural analysis, the test apparatus, and the test execution/results.

Stubbs, David M.; Hom, Craig L.; Holmes, Howard C.; Cannon-Morret, Joseph C.; Lindstrom, Obert F.; Irwin, J. Wes; Ryder, Leigh A.; Hix, Troy T.; Bonvallet, Jane A.; Hu, Hsin-Kuei S.; Chapman, Ira V.; Lomax, Curtis; Kvamme, E. Todd; Feller, Gregory S.; Haynes, Mark M.

2011-09-01

246

Flight Performance of the AKARI Cryogenic System  

E-print Network

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

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

2007-08-14

247

Acquisition/expulsion system for earth orbital propulsion system study. Volume 1: Summary report. [cryogenic storage and fuel flow regulation system for space shuttle orbiter  

NASA Technical Reports Server (NTRS)

Design, construction, and quality control tests on a dual screen liner device for the space shuttle orbiter cryogenic fuel tank and feedliner system are summarized. The dual stainless steel mesh of the device encloses eight liquid fuel channels and provides the liquid/vapor interface stability required for low gravity orbits.

1973-01-01

248

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

Microsoft Academic Search

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

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

2001-01-01

249

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

250

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

E-print Network

is to investigate how delivery nozzle design influences the cooling rate of cryogen spray as used in skin laser injector valve without delivery nozzle [7,8]. In this paper, we investigate how changes in nozzle design treatments. Cryogen was sprayed through nozzles that consist of metal tubes with either a narrow or wide

Aguilar, Guillermo

251

On-board cryogenic system for magnetic levitation of trains - Cryogenic system of EET  

Microsoft Academic Search

An experimental car based on electrodynamic levitation with superconducting magnets has been developed and manufactured by AEG, BBC, Siemens and other partners, together with Linde AG as the firm responsible for the onboard cryogenic system. This system has to cope with new conditions and cryogenic tasks. It can be characterized in principle by liquid helium heat exchanger units, compressors, transfer

S. Asztalos; W. Baldus; R. Kneuer; A. Stephan; K. Mendelssohn

1974-01-01

252

On-board cryogenic system for magnetic levitation of trains - Cryogenic system of EET  

Microsoft Academic Search

The present work gives a general description of the cryogenic system of an experimental electrodynamic levitation car. Cooling of the magnet coils is provided by a forced LHe stream. The cryogenic system represents a compromise between the exclusive use of evaporation heat (LHe bath only) and a closed-cycle refrigerator. The system consists mainly of a LHe tank-heat exchanger unit, compressor,

S. Asztalos; W. Baldus; R. Kneuer; A. Stephan

1975-01-01

253

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

254

Carbon nanotube electrical-substitution cryogenic radiometer: initial results.  

PubMed

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

Tomlin, N A; Lehman, J H

2013-01-15

255

Cryogenic pellet production developments for long-pulse plasma operation  

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

256

Development of cryogenic load-pull analysis: power amplifier technology performance trends  

Microsoft Academic Search

On-wafer load-pull measurements at cryogenic temperatures are made for the first time on FET power amplifier structures to demonstrate the improved performance when operated at reduced temperatures. Measurements from 300 K to 17 K demonstrate improvements in both efficiency (40-80%) and output power (1.0-2.7 dB). These results demonstrate that advanced device technologies that are optimized for cooled operation may provide

Edward Gebara; Joy Laskar; Mike Harris; T. Kikel

1998-01-01

257

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

Microsoft Academic Search

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

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

1990-01-01

258

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

259

Ultrahigh efficiency power conversion using cryogenic MOSFETs and HT-superconductors  

Microsoft Academic Search

Ultra-high efficiency (>99%) power conversion and the corresponding energy savings can be accomplished by combining two new devices: the cryogenic power MOSFET and the high current inductor made with high-temperature (HT) superconductors. Their properties are reviewed. Several possible applications are discussed such as high-power inverters, switchmode amplifiers, and multi-kilowatt RF generators. Design information is presented for the thermal losses of

O. M. Mueller; K. G. Herd

1993-01-01

260

MESFET cryogenic front-end for cross-correlation noise measurements  

Microsoft Academic Search

We present a dual-channel transimpedance amplifier for cross-correlation noise measurements with a MESFET cryogenic front-end and cooled feedback resistors. In order to test the noise performance of the system, devices with known noise power spectral density (i.e. resistors) have been measured. In particular, such a system has been able to reliably measure a noise current spectral density lower than 1

G. Fiori; L. Guidi; M. Macucci; G. Basso; I. Maione; B. Pellegrini

2007-01-01

261

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

262

Cryogenic silicon surface ion trap  

E-print Network

Trapped ions are pre-eminent candidates for building quantum information processors and quantum simulators. They have been used to demonstrate quantum gates and algorithms, quantum error correction, and basic quantum simulations. However, to realise the full potential of such systems and make scalable trapped-ion quantum computing a reality, there exist a number of practical problems which must be solved. These include tackling the observed high ion-heating rates and creating scalable trap structures which can be simply and reliably produced. Here, we report on cryogenically operated silicon ion traps which can be rapidly and easily fabricated using standard semiconductor technologies. Single $^{40}$Ca$^+$ ions have been trapped and used to characterize the trap operation. Long ion lifetimes were observed with the traps exhibiting heating rates as low as $\\dot{\\bar{n}}=$ 0.33 phonons/s at an ion-electrode distance of 230 $\\mu$m. These results open many new avenues to arrays of micro-fabricated ion traps.

Michael Niedermayr; Kirill Lakhmanskiy; Muir Kumph; Stefan Partel; Johannes Edlinger; Michael Brownnutt; Rainer Blatt

2014-03-20

263

A Cryogenic Infrared Calibration Target  

E-print Network

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

Wollack, Edward J; Rinehart, Stephan A

2014-01-01

264

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

265

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

266

Status of the ESS cryogenic system  

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

267

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

268

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

269

Cryogenic System for the Spallation Neutron Source  

NASA Astrophysics Data System (ADS)

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.

2004-06-01

270

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

271

Notes on Single-Particle Reconstruction in Cryogenic  

E-print Network

Notes on Single-Particle Reconstruction in Cryogenic Electron Microscopy Hemant D. Tagare-dimensional structure of macromolecules. A more modern method is cryogenic electron microscopy (cryo-em), which

Duncan, James S.

272

Long-Lived Linear-Motion Suspension For Cryogenic Instrument  

NASA Technical Reports Server (NTRS)

Mechanism suspends optical component in cryogenic instrument in such way to allow component to translate smoothly along one axis, without vibration. Bearings located outside cooled instrument chamber for longer life. Thermal isolators separate bearings from cryogenic environment inside instrument chamber.

Packard, Douglas T.; Agronin, Michael L.

1995-01-01

273

49 CFR 173.320 - Cryogenic liquids; exceptions.  

Code of Federal Regulations, 2010 CFR

...Cryogenic liquids; exceptions. (a) Atmospheric gases and helium, cryogenic liquids, in Dewar flasks, insulated cylinders...requirements of this subchapter do not apply to atmospheric gases and helium: (1) During loading and unloading operations...

2010-10-01

274

49 CFR 173.320 - Cryogenic liquids; exceptions.  

...Cryogenic liquids; exceptions. (a) Atmospheric gases and helium, cryogenic liquids, in Dewar flasks, insulated cylinders...requirements of this subchapter do not apply to atmospheric gases and helium: (1) During loading and unloading operations...

2014-10-01

275

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

276

Cryogenic neutron moderator on mesitylene pellets for IBR-2 reactor  

E-print Network

Cryogenic neutron moderator on mesitylene pellets for IBR-2 reactor Anan'ev V., Belyakov A mesitylene receiver 1 2 3 4 5 6 7 9 8 HeHe #12;Cryogenic transport pipeline for moderators of 2-3 and 7- 10 of the IBR-2M cryogenic moderator 1 2 3 5 4 1 ­ camera-imitator of cryogenic moderator, 2 ­thermal exchanger

Titov, Anatoly

277

Advances in Cryogenic Avalanche Detectors (review)  

E-print Network

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

A. Buzulutskov

2011-12-28

278

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

279

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

280

Continuous Cryogenic He-3 Adsorption Pump Harry Charalambous, David Schuster  

E-print Network

Continuous Cryogenic He-3 Adsorption Pump Harry Charalambous, David Schuster 8/22/14 Abstract of the Pulse Tube Refrigerator as an Efficient and Reliable Cryocooler. Web. http://www.cryogenics and Technology. Development of the Pulse Tube Refrigerator as an Efficient and Reliable Cryocooler. Web. http://www.cryogenics

Lombardi, John R.

281

TT2A Mercury Jet Experiment The Cryogenic  

E-print Network

TT2A Mercury Jet Experiment The Cryogenic System Roger Bennett and Yury Ivanyushenkov CCLRC "SPECIFICATION" of the cryogenic cycle is: 1. Initial fill of the magnet cryostat slowly over many hours -12 at CERN, December 2004, drawn by Peter Titus #12;Design and Costing of the Cryogenic System 1. The input

McDonald, Kirk

282

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

283

Dynamic Cryogenic Seals to Support Fueling of Fusion Tokomaks  

E-print Network

Dynamic Cryogenic Seals to Support Fueling of Fusion Tokomaks U. Naranjo and J. W. Leachman School in damaged products every year. Sealing at cryogenic temperatures is a substantially more difficult task than extruder in development at the WSU HYPER laboratory. The purpose of a cryogenic dynamic polymer seal

Collins, Gary S.

284

Studies of Cryogenic Electron Plasmas in Magnetic Mirror Fields  

E-print Network

Studies of Cryogenic Electron Plasmas in Magnetic Mirror Fields by Ramesh Gopalan A.B. (University: Chair Date Date Date University of California at Berkeley 1998 #12;Studies of Cryogenic Electron Plasmas in Magnetic Mirror Fields Copyright 1998 by Ramesh Gopalan #12;1 Abstract Studies of Cryogenic Electron

Fajans, Joel

285

THE SNS CRYOGENIC CONTROL SYSTEM: EXPERIENCES IN COLLABORATION [1  

E-print Network

WEAP013 THE SNS CRYOGENIC CONTROL SYSTEM: EXPERIENCES IN COLLABORATION [1] W. H. Strong, P. A. Gurd Abstract The cryogenic system for the Spallation Neutron Source (SNS) is designed by Jefferson Laboratory, and software tools. The cryogenic system is the first SNS system to be developed using SNS standards

286

An all-cryogenic THz transmission spectrometer P. J. Burkea)  

E-print Network

An all-cryogenic THz transmission spectrometer P. J. Burkea) and J. P. Eisenstein Condensed Matter contained in a cryogenic environment. Cyclotron emission from a two-dimensional electron gas 2DEG heated microwave to optical frequencies.2 In this article an all-cryogenic spectrometer is presented that bypasses

Eisenstein, Jim

287

Cryogenic Roadmap U.S. Department of Energy  

E-print Network

i Cryogenic Roadmap U.S. Department of Energy Superconductivity Program for Electric Systems Executive Summary Cryogenic systems providing 100-1000 watts of cooling power at 65-80 K are required) and operate more efficiently (30+% of Carnot) and reliably than present day off the shelf cryogenic systems

288

Interaction of Cryogen Spray with Human Skin under Vacuum Pressures  

E-print Network

Interaction of Cryogen Spray with Human Skin under Vacuum Pressures Walfre Franco, Jie Liu vessels in port wine stains (PWS) birthmarks laser therapy. The release of cryogen spurts under vacuum is to study the time and space dependent thermal response of a skin phantom to cryogen sprays at different

Aguilar, Guillermo

289

Optical links for cryogenic focal plane array Alan R. Johnston  

E-print Network

Optical links for cryogenic focal plane array readout Alan R. Johnston Duncan T. H. Liu, MEMBER@jplopto.jpl.nasa.gov 1 Introduction Optical instruments employing cryogenic focal plane arrays must minimize power dissipation on the focal plane. Because cooler power efficiency is low at cryogenic temperatures, reduction

Fossum, Eric R.

290

Cryogenic Roadmap U.S. Department of Energy  

E-print Network

06/18/01 1 Cryogenic Roadmap U.S. Department of Energy Superconductivity Program for Electric pertaining to cryogenics. Appendix A is a tabulation of the steering committee members who participated by the steering committee and the 1997 and 1998 cryogenic workshop findings. However, there are added

291

49 CFR 173.319 - Cryogenic liquids in tank cars.  

...2014-10-01 2014-10-01 false Cryogenic liquids in tank cars. 173.319 Section 173...and Packaging § 173.319 Cryogenic liquids in tank cars. (a) General requirements...tank car containing a flammable cryogenic liquid may not be shipped unless it was...

2014-10-01

292

49 CFR 173.316 - Cryogenic liquids in cylinders.  

...2014-10-01 2014-10-01 false Cryogenic liquids in cylinders. 173.316 Section 173...and Packaging § 173.316 Cryogenic liquids in cylinders. (a) General requirements...cylinder may not be loaded with a cryogenic liquid colder than the design service...

2014-10-01

293

49 CFR 173.318 - Cryogenic liquids in cargo tanks.  

...2014-10-01 2014-10-01 false Cryogenic liquids in cargo tanks. 173.318 Section...and Packaging § 173.318 Cryogenic liquids in cargo tanks. (a) General requirements...tank may not be loaded with a cryogenic liquid colder than the design service...

2014-10-01

294

Method of measuring heat influx of a cryogenic transfer system  

Microsoft Academic Search

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

Ralph C. Niemann; Steven A. Zelipsky; Ronald R. Rezmer; Peter Smelser

1981-01-01

295

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

296

Development of the Los Alamos National Laboratory Cryogenic Pressure Loader  

Microsoft Academic Search

Targets for inertial fusion research and ignition at OMEGA, the National Ignition Facility, LMJ, and future facilities rely on beta-radiation-driven layering of spherical cryogenic DT ice layers contained within plastic or metal shells. Plastic shells will be permeation filled at room temperature then cooled to cryogenic temperatures before removal of the overpressure. The cryogenic pressure loader (CPL) was recently developed

Peter S. Ebey; James M. Dole; James K. Hoffer; Joseph E. Nasise; Arthur Nobile; Robert L. Nolen; John D. Sheliak

2003-01-01

297

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

298

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

299

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

300

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

301

Cryogenic insulation standard data and methodologies  

NASA Astrophysics Data System (ADS)

Although some standards exist for thermal insulation, few address the sub-ambient temperature range and cold-side temperatures below 100 K. Standards for cryogenic insulation systems require cryostat testing and data analysis that will allow the development of the tools needed by design engineers and thermal analysts for the design of practical cryogenic systems. Thus, this critically important information can provide reliable data and methodologies for industrial efficiency and energy conservation. Two Task Groups have been established in the area of cryogenic insulation systems Under ASTM International's Committee C16 on Thermal Insulation. These are WK29609 - New Standard for Thermal Performance Testing of Cryogenic Insulation Systems and WK29608 - Standard Practice for Multilayer Insulation in Cryogenic Service. The Cryogenics Test Laboratory of NASA Kennedy Space Center and the Thermal Energy Laboratory of LeTourneau University are conducting Inter-Laboratory Study (ILS) of selected insulation materials. Each lab carries out the measurements of thermal properties of these materials using identical flat-plate boil-off calorimeter instruments. Parallel testing will provide the comparisons necessary to validate the measurements and methodologies. Here we discuss test methods, some initial data in relation to the experimental approach, and the manner reporting the thermal performance data. This initial study of insulation materials for sub-ambient temperature applications is aimed at paving the way for further ILS comparative efforts that will produce standard data sets for several commercial materials. Discrepancies found between measurements will be used to improve the testing and data reduction techniques being developed as part of the future ASTM International standards.

Demko, J. A.; Fesmire, J. E.; Johnson, W. L.; Swanger, A. M.

2014-01-01

302

Cryogenic system of the MAX-Wiggler  

NASA Astrophysics Data System (ADS)

A novel insertion device for electron storage rings called the MAX-Wiggler has been constructed and commissioned at MAX-lab. The MAX-Wiggler is a cold bore superconducting wiggler magnet with 47 3.5 T poles and a period length of 61 mm aimed for the production of X-rays at the 1.5 GeV electron storage ring MAX-II at MAX-lab. This note describes the cryogenic system of the MAX-Wiggler, theoretical predictions of the heat loads to the cryostat, and measured heat loads at operation. The cryostat is a helium cooled bath type cryostat. The design criterion for the cryostat was to have a liquid He boil-off less than 3 l/h, which corresponds to a heat load of 2.1 W. The theoretical calculations predicted a heat load of 0.87 W to the liquid He bath. Of the 0.87 W predicted heat load, 0.17 W was predicted to be induced by the stored beam in MAX-II, 0.12 W from synchrotron radiation and 0.05 W from image currents. The measured heat load to the liquid He bath is larger than predicted from the theoretical calculations and at nominal working conditions it is 1.7 W. The measured contribution to the total heat load from the stored beam of 200 mA in MAX-II is 0.86 W, 0.59 W from image currents and 0.26 W from synchrotron radiation. The measured contribution from the image current is 0.59 W, about 10 times larger than expected from the theoretical calculations, which is assumed to depend on that the Cu plating of the inner surfaces of the cold bore has a lower electrical conductivity than foreseen. The higher than expected heat load from synchrotron radiation is assumed to come from a positioning error of the upstream absorber for synchrotron radiation. There is no observable increase of the heat load with the wiggler at full field. Even though the heat loads are higher than expected, the design criterion of obtaining a cryostat with a liquid He boil-off inferior to 3 l/h with 200 mA of stored current in MAX-II has been met.

Wallén, Erik; LeBlanc, Greg

2004-12-01

303

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

304

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

305

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

306

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

307

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

NASA Astrophysics Data System (ADS)

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.; Kakeshita, T.

2004-06-01

308

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

309

Cryogenic and Electrical Test Results of 30 M Hts Power Cable  

NASA Astrophysics Data System (ADS)

In the framework of the Russian R&D Program for HTS power devices, 3×30 m cable with operating current of ˜1.5-2 kA and operating voltage of 20 kV was delivered by Russian Scientific R&D Cable Institute as the first stage of the HTS power cables project. Different basic HTS materials, cryostats and current leads were used for the cable design in this essentially research part of the project. The cable is being tested at special test facility for superconducting power devices developed at the R&D Center for Power Engineering. The cryogenic system for the test facility was provided by Stirling. The basic cryogenic system was equipped with a specially developed flow distribution unit. This unit permits variation and control of liquid nitrogen flows, pressures and temperatures in all three cable phases. Dependencies on temperature of critical currents of each phase were measured during cable tests. The results of the project]s first stage were used to develop and produce a 3×200 m cable system for Moscow distribution grid. In the paper results of cryogenic system tests and cable electrical tests are presented.

Sytnikov, V. E.; Vysotsky, V. S.; Fetisov, S. S.; Nosov, A. A.; Shakaryan, Yu. G.; Kochkin, V. I.; Kiselev, A. N.; Terentyev, Yu. A.; Patrikeev, V. M.; Zubko, V. V.

2010-04-01

310

Improved Multi-octave 3 dB IF Hybrid for Radio Astronomy Cryogenic Receivers  

NASA Astrophysics Data System (ADS)

Modern mm and sub-mm ultra low noise receivers used for Radio Astronomy have evolved to provide very wide instantaneous bandwidth. Some of the configurations used in present cryogenic front-ends, like sideband separating mixers and balanced amplifiers, need 90° 3 dB hybrids at the IF, typically in the 4-12 GHz band. There are commercially available devices covering this band with good ambient temperature characteristics, but poor cryogenic performance. We describe the design, construction and measurement of a multioctave stripline hybrid for the 4-12 GHz band specially conceived to perform reliably when cooled to 15 K. The coupling and reflection show very little temperature dependence. A balanced cryogenic amplifier was assembled with two 3 dB hybrid units and available amplifiers (~4.5 K noise temperature) designed and built in-house for ALMA. This device is critically compared with a single ended amplifier and with an amplifier with an input isolator. The latter is the typical arrangement of the IF of radio astronomy receivers. The balanced option shows an advantage of 2.8 K in noise with less sensitivity to input mismatches.

Malo, I.; Gallego, J.; Diez, C.; López-Fernández, I.; Briso, C.

2009-04-01

311

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

312

Cryogenic fluid flow instabilities in heat exchangers  

NASA Technical Reports Server (NTRS)

Analytical and experimental investigation determines the nature of oscillations and instabilities that occur in the flow of two-phase cryogenic fluids at both subcritical and supercritical pressures in heat exchangers. Test results with varying system parameters suggest certain design approaches with regard to heat exchanger geometry.

Fleming, R. B.; Staub, F. W.

1969-01-01

313

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

314

Infrared filters for cryogenic millimeterwave receivers  

Microsoft Academic Search

Filters are required to block infrared radiation from the low temperature regions of cryogenic receivers to reduce thermal loading and temperature gradients. The design and analysis of PTFE filters mounted on the radiation shield of a closed-cycle Joule-Thompson 4 K refrigerator is described. Calculations of the thennal transmission and emission of the filters are compared with measurements. It was found

James W. Lamb

1993-01-01

315

CIRRIS 1A cryogen system performance  

Microsoft Academic Search

The Cryogenic InfraRed Radiance Instrumentation for Shuttle (CIRRIS 1A) instrument, successfully flown and operated on the Shuttle Discovery from 28 April to 6 May 1991, was designed to operate at supercritical helium temperatures. During flight, the focal plane temperature control and telescope contamination purge systems performed as designed and 36 hours of excellent data was obtained; however, the parasitic helium

E. W. Vendell; David E. Morse; Andrew Landoch

1993-01-01

316

Cryogenic Filters for RFI Mitigation in Radioastronomy  

E-print Network

RFI mitigation in Radioastronomy can be achieved adopting cryogenic filters in appropriate typologies. A study has been conducted in L, C and X band with the evaluation of the filter architecture in copper, with theoretical estimation, computer simulations, prototypes realization, laboratory measurements. Such work has been preliminary to the realization of HTS samples with the purpose of a similar complete characterization approach.

G. Tuccari; A. Caddemi; S. Barbarino; G. Nicotra; F. Consoli; F. Schilliro; F. Catalfamo

2005-01-03

317

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

318

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

319

Cryogenics Testbed Laboratory Flange Baseline Configuration  

NASA Technical Reports Server (NTRS)

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

Acuna, Marie Lei Ysabel D.

2013-01-01

320

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

321

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

322

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

323

Stabilizing stainless steel components for cryogenic service  

NASA Technical Reports Server (NTRS)

Warpage and creep in stainless steel valve components are decreased by a procedure in which components are machined to a semifinish and then cold soaked in a bath of cryogenic liquid. After the treatment they are returned to ambient temperature and machine finished to the final drawing dimensions.

Holden, C. F.

1967-01-01

324

Cryogenics: Producing a state of suspended reality  

Microsoft Academic Search

This paper explores the phenomenon of cryogenics, and its impact on current conceptualizations about death within social psychology. As an alternative to traditional death ritualization, evaluation of the use of cryonic suspension is offered to show how the technique accommodates the denial of death, feeds on narcissistic values, and aids in the secularization of technology over religion. Finally, the fundamental

J. Smith Teitge

1984-01-01

325

Piston sealing arrangement for a cryogenic refrigerator  

SciTech Connect

A sealing arrangement for a rectilinear reciprocable piston within a cryogenic refrigerator comprising a buffer defined by dual O-rings disposed around the circumference of the piston and containing pressurized gas of the same type as the refrigeration gas. The buffer limits or prevents both the entrance of contaminants and also the escape of the refrigeration gas.

Green, G.F.; Humphrey, J.C.

1984-02-21

326

Three-axis cryogenic Hall sensor  

Microsoft Academic Search

Magnetic field measurements are very important for magnetic and superconducting material research. Hall sensors have many advantages for these measurements. They can also be used for magnetic field profile measurements, which provide information about material homogeneity. We have developed a three-axis Hall system which consists of three perpendicular InSb Hall sensors for operation at room as well as cryogenic temperatures.

J. Kvitkovic; M. Majoros

1996-01-01

327

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

328

Miniature cryogenic expansion turbines - A review  

Microsoft Academic Search

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

H. Sixsmith

1984-01-01

329

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

330

Multiphasic pump for rotating cryogenic machinery  

Microsoft Academic Search

A mixed phase pump for rapidly rotating cryogenic machinery is disclosed, preferably for installation to a superconducting generator rotor. The superconducting generator rotor includes an inner and outer rotor structure joined in a thermally insulated configuration not unlike that of a dewar flask. The inner rotor contains a support cylinder for a refrigerant, typically helium, which when refrigerated to 3.5*

Eckels

1980-01-01

331

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

332

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

333

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

334

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

335

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

336

Cryogenic cooling program in high heat load optics at the Advanced Photon Source  

NASA Astrophysics Data System (ADS)

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, Carey S.

1993-11-01

337

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

338

Cryogenic systems for the large deployable reflector  

NASA Technical Reports Server (NTRS)

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

Mason, Peter V.

1988-01-01

339

Cryogenic measurements of aerojet GaAs n-JFETs  

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

340

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

341

Neutron spin manipulation devices using YBCO films  

NASA Astrophysics Data System (ADS)

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

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

2014-07-01

342

Modifications developed to improve x-ray detection devices  

NASA Technical Reports Server (NTRS)

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

1994-01-01

343

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

344

Cryogenic Optical Systems and Instrumentation IX (AM 116) Newly Modified Cryogenic Optical Test Facility at the Marshall Space Flight Center  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center (MSFC) has maintained and operated a world-class x-ray optics and detector testing facility known as the X-ray Calibration Facility (XRCF) since the mid 1970's. The ground test and calibration of the Chandra X-ray Observatory optics and detectors were successfully completed at the XRCF in 1997. The beginning of the Next Generation Space Telescope (NGST) development programs (NMSD, SBMD, AMSD, etc.) and the establishment of the Space Optics Manufacturing Technology Center at MSFC have led to an XRCF modification. In 1999 the facility was upgraded to perform cryogenic testing of lightweight visible optics (without compromising the existing x-ray testing capability). A thermal enclosure capable of 20 degrees Kelvin and vibration isolated instrumentation mount were added. A vacuum-compatible five-axis motion table was modified to operate under cryogenic conditions. Optics up to two meters in diameter with radii of curvature of up to twenty meters can be accommodated. Facility characterization tests and one NGST program mirror test have been completed to date. By July 2000, two other mirrors will be tested. Optical wavefront measurements were made at < 35 degrees Kelvin with several instruments located at the test mirror's radius of curvature. The current wavefront measuring instruments include a Shack-Hartman wavefront sensor, a point diffraction interferometer, a point spread function-measuring device, and a radius of curvature measuring instrument. A vibration insensitive phase shifting interferometer is planned for future optical testing. This paper will present a brief history of the facility, a discussion of its current x-ray optic testing capabilities, and a complete description of the new capabilities in the visible optical testing regime.

Eng, Ronnie; Kegley, Jeff; Keidel, John

2000-01-01

345

Noiseless nonreciprocity in a parametric active device  

E-print Network

Nonreciprocal devices such as circulators and isolators belong to an important class of microwave components employed in applications like the measurement of mesoscopic circuits at cryogenic temperatures. The measurement protocols usually involve an amplification chain which relies on circulators to separate input and output channels and to suppress backaction from different stages on the sample under test. In these devices the usual reciprocal symmetry of circuits is broken by the phenomenon of Faraday rotation based on magnetic materials and fields. However, magnets are averse to on-chip integration, and magnetic fields are deleterious to delicate superconducting devices. Here we present a new proposal combining two stages of parametric modulation emulating the action of a circulator. It is devoid of magnetic components and suitable for on-chip integration. As the design is free of any dissipative elements and based on reversible operation, the device operates noiselessly, giving it an important advantage over other nonreciprocal active devices for quantum information processing applications.

Archana Kamal; John Clarke; Michel Devoret

2010-10-08

346

Designs of pulsed power cryogenic transformers  

SciTech Connect

The Westinghouse Electric Corporation has completed designs 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 electromagnetic launcher and form a three-stage power supply. The pulse transformers will act as two winding energy storage solenoids which provide a high current and energy pulse compression by transforming a 50 kA power supply into a megamp level power supply more appropriate for the electromagnetic launcher duty. This system differs from more traditional transformer applications in that significant current levels do not exist simultaneously in the two windings of the pulse transformer. This paper describes the designs of the pulsed power cryogenic transformers.

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

1987-09-01

347

Cryogenic Design of the Aluheat Project  

NASA Astrophysics Data System (ADS)

ALUHEAT project aims to build a cryogen-free superconducting induction heater. In this paper, the cryogenic design, which includes heat loss calculations, mechanical analysis, optimization of current leads and description of cooling conditions, is presented in detail. The induction heater consists of two magnets in separate cryostats and the billet to be heated is rotated between the cryostats. Short distance between the magnet and cryostat wall, large forces between the magnets, and the need to rotate the billet create application specific requirements that must be taken into account. Finite element analysis is used to design the cryostat to withstand the forces created by the vacuum and magnetic field. Finally, thermal interface, radiation shield, magnet support and apparatus to rotate the billet are designed and all components assembled into the complete system.

Hiltunen, I.; Stenvall, A.; Korpela, A.; Lehtonen, J.; Mikkonen, R.; Runde, M.; Magnusson, N.; Kalkowski, G.

2008-03-01

348

Performance of small high pressure cryogenic pumps  

NASA Astrophysics Data System (ADS)

Two small cryogenic pumps have been made and tested for use in LO2/LH2 rocket-engine turbopumps. Both the pumps have a small impeller and are characterized by high speed and high delivery pressure. The main design characteristics of the pumps are as follows: rotational speeds 45,000 and 80,000 rpm, delivery pressures 24.6 and 26.0 MPa, and flow rates 0.016 and 0.0439 cu m/s, for LO2 and LH2 pumps, respectively. The efficiencies of the test pumps were compared with previously reported results, and the adiabatic efficiency (usually used for compressors or gas turbines) was investigated in more detail to demonstrate its applicability to cryogenic pumps.

Kamijo, K.; Watanabe, M.; Hasegawa, S.

349

Cryogenic Infrared Radiance Instrumentation For Shuttle (CIRRIS)  

NASA Astrophysics Data System (ADS)

In recent years, the Air Force Geophysics Laboratory has flown several rocketborne experiments with cryogenic interferometers to measure natural and induced infrared atmospheric emissions. AFGL is currently developing two separate shuttle payloads based on advanced versions of these rocket sensors mated to cryogenic high off-axis rejection telescopes. CIRRIS will have a spectral resolution capability of better than 1 cm-1 over the 4 - 25 ?m region, and will be dedicated to measurements of infrared emissions from the earthlimb at altitudes from 30 - 300 km. CIRRIS data is expected to provide an assessment of the effects of the atmosphere on current and planned AF space systems and a comprehensive data base for atmospheric modelling. Additional CIRRIS objectives are to measure and assess the effects of shuttle contamination on other planned shuttle experiments and to obtain data on a large number of atmospheric trace species. Specifics of the CIRRIS instrument, measurement plan and capabilities are presented.

Smith, D. R.; Stair, A. T., Jr.; Steed, A. J.; Burt, D. A.

1981-04-01

350

Cryogenic hydrogen circulation system of neutron source  

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

351

Transition detection studies in the cryogenic environment  

NASA Technical Reports Server (NTRS)

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 factors including the wind tunnel operation mode, the model construction materials and the IR system image processing options. During the initial phases of the study, the IR based findings were confirmed by measurements done with a micro-thin hot-film system. Ultimately, free and forced transition could be detected down to 170 K.

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

1990-01-01

352

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

353

Absorber Materials at Room and Cryogenic Temperatures  

SciTech Connect

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

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

2011-09-01

354

Cryogenic cooling for high power laser amplifiers  

NASA Astrophysics Data System (ADS)

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

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

2013-11-01

355

IRAS cryogenic system flight performance report  

NASA Technical Reports Server (NTRS)

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

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

1984-01-01

356

Bonding and Sealing Evaluations for Cryogenic Tanks  

NASA Technical Reports Server (NTRS)

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 within Gr/Ep. In addition to these tests, flatwise adhesion pull off tests were performed at room temperature with PR 1664, EA 9394, FM-300, Crest 3170, and HT 435 adhesives. The materials bonded included Gr/Ep, Gr/BMI, Al, and stainless steel facesheets, and Ti honeycomb, Hexcel honeycomb, and Rohacell foam core materials.

Glass, David E.

1997-01-01

357

Test of a cryogenic helium pump  

SciTech Connect

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

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

1981-01-01

358

Cryogenic helium 2 systems for space applications  

NASA Technical Reports Server (NTRS)

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

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

1978-01-01

359

Radiation fin effects in cryogen systems  

NASA Astrophysics Data System (ADS)

This paper presents an analytical treatment of radiation fin effects in cryogen systems. Two similar structures, an annular support structure and a vapor-cooled shield, are treated as fins where the heat transfer from their surfaces is assumed to be primarily radiative. The resulting non-linear differential equation is non-dimensionalized and solved numerically with the boundary conditions appropriate for each problem. Dimensionless parameters are introduced that may be used to analyze the actual heat transfer for both cases, as well as to indicate when the fin effect is negligible. The results are presented in terms of the increase or decrease in heat transfer with respect to easily calculated reference cases. It is shown that when the thermal conductance on each side of the fins may be adjusted there exists an optimum conductance ratio that minimizes the heat load to the cryogen.

Lee, Ron C.

1989-06-01

360

Feasibility study for the Cryogenic Orbital Nitrogen Experiment (CONE)  

NASA Technical Reports Server (NTRS)

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

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

1991-01-01

361

Method and apparatus for producing cryogenic targets  

DOEpatents

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

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

1984-08-07

362

Material Selection for Cryogenic Support Structures  

NASA Astrophysics Data System (ADS)

Design specifications for the support structures of low temperature instrumentation often call for low thermal conductivity between temperature stages, high stiffness, and specific load bearing capabilities. While overall geometric design plays an important role in both overall stiffness and heat conduction between stages, material selection can affect a structure's properties significantly. In this contribution, we suggest and compare several alternative materials to the current standard materials for building cryogenic support structures.

Kramer, Erik; Kellaris, Nicholas; Daal, Miguel; Sadoulet, Bernard; Golwala, Sunil; Hollister, Matthew

2014-09-01

363

Cryogenic regenerator including sarancarbon heat conduction matrix  

NASA Technical Reports Server (NTRS)

A saran carbon matrix is employed to conduct heat through the heat storing volume of a cryogenic regenerator. When helium is adsorbed into the saran carbon matrix, the combination exhibits a volumetric specific heat much higher than previously used lead balls. A helium adsorbed saran regenerator should allow much lower refrigerator temperatures than those practically obtainable with lead based regenerators for regenerator type refrigeration systems.

Jones, Jack A. (Inventor); Petrick, S. Walter (Inventor); Britcliffe, Michael J. (Inventor)

1989-01-01

364

Method and apparatus for producing cryogenic targets  

DOEpatents

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

Murphy, James T. (Los Alamos, NM); Miller, John R. (Penfield, NY)

1984-01-01

365

Cryogenic preservation of fish and mammalian spermatozoa  

Microsoft Academic Search

Summary. Various combinations of sucrose, reduced glutathione and potassium bi- carbonate were tested for the cryogenic preservation of salmon spermatozoa. When a fast freezing procedure was followed, the extender that gave the best results was composed of 1 part ofdimethyl sulphoxide (DMSO), as a protective agent, and 7 parts of a medium containing 125 mM-sucrose, 6.50 mM-reduced glutathione and 100

M. S. Mounib

1978-01-01

366

Cryogenic properties of optomechanical silica microcavities  

E-print Network

We present the optical and mechanical properties of high-Q fused silica microtoroidal resonators at cryogenic temperatures (down to 1.6 K). A thermally induced optical multistability is observed and theoretically described; it serves to characterize quantitatively the static heating induced by light absorption. Moreover the influence of structural defect states in glass on the toroid mechanical properties is observed and the resulting implications of cavity optomechanical systems on the study of mechanical dissipation discussed.

Olivier Arcizet; Rémi Rivière; Albert Schliesser; Tobias J. Kippenberg

2009-01-09

367

Superconductors and cryogenics for future communication systems  

Microsoft Academic Search

In the framework of a German research program on “superconductors and ceramics for future communication technology”, efforts are undertaken to demonstrate the feasibility of cryogenic and high-temperature superconductor technology for applications in communication satellites and base transceiver stations (BTS's) for terrestrial mobile communication. For the receiver front end of C-band satellites, noise reduction filters as well as input-multiplexer channel filters

Matthias Klauda; T. Kasser; B. Mayer; C. Neumann; F. Schnell; B. Aminov; A. Baumfalk; H. Chaloupka; S. Kolesov; H. Piel; N. Klein; S. Schornstein; M. Bareiss

2000-01-01

368

Transportation of hydrocarbons by cryogenic pipeline  

Microsoft Academic Search

A preliminary design and economic feasibility studies of the cryogenic transport of natural gas, and of natural gas-crude oil as a slurry were carried out. These two basic pipelines were investigated for two different temperature and pressure level designs, a cold -258°F, 1000 psia design and a warmer -140°F, 740 psia design. The design parameters of both the LNG only

Coulter

1977-01-01

369

Cryogenic adhesives and sealants: Abstracted publications  

NASA Technical Reports Server (NTRS)

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

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

1977-01-01

370

PRESSURE OSCILLATION IN RHIC CRYOGENIC SYSTEM.  

SciTech Connect

HORIZONTAL BEAM VIBRATION AROUND 10HZ IN THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) HAVE BEEN IDENTIFIED AND THE POSSIBLE SOURCES TO CAUSE THIS VIBRATION HAVE BEEN INVESTIGATED. TO DETERMINE THE HETIUM PRESSURE OSCILLATIONS AS A POSSIBLE PRIMARY VIBRATION SOURCE, HELIUM PRESSURE MEASUREMENTS WERE CARRIED OUT IN THE FIVE CRYOGENIC TRANSFER LINES AT 2 VALVE BOXES AND 6 LEAD PORTS AT 2 TRIPLET CRYOSTAT FOR BOTH MAGNET RINGS. ADDITIONALLY, COLD MA...

JIA,L.MONTAG,C.TALLERICO,T.HIRZEL,W.NICOLETTI,A.

2003-09-22

371

Cryogenic Treatment of Tool Materials: A Review  

Microsoft Academic Search

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

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

2010-01-01

372

Strong, Ductile Rotor For Cryogenic Flowmeters  

NASA Technical Reports Server (NTRS)

Improved magnetic flowmeter rotor resists cracking at cryogenic temperatures, yet provides adequate signal to magnetic pickup outside flowmeter housing. Consists mostly of stainless-steel alloy 347, which is ductile and strong at low temperatures. Small bead of stainless-steel alloy 410 welded in groove around circumference of round bar of stainless-steel alloy 347; then rotor machined from bar. Tips of rotor blades contain small amounts of magnetic alloy, and passage of tips detected.

Royals, W. T.

1993-01-01

373

Active Control of Cryogenic Propellants in Space  

NASA Technical Reports Server (NTRS)

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

Notardonato, William

2011-01-01

374

Cryogenic temperature measurement for large applications  

E-print Network

We have developed a resistance thermometry system for the acquisition, control and monitoring of temperature in large-scale cryogenic applications. The resistance of the sensor is converted to a voltage using a self-balancing AC bridge circuit featuring square-wave excitation currents down to 1 nA. The system is easily scalable and includes intelligent features to treat special situations such as magnet quenches differently from normal operation.

Ylöstalo, J; Kyynäräinen, J; Niinikoski, T O; Voutilainen, R

1996-01-01

375

15 ps cryogenic operation of 0.19-?m-LG n+ - p+ double-gate SOI CMOS  

NASA Astrophysics Data System (ADS)

We demonstrated a CMOS invertor with a 15 ps propagation delay (tpd) at 77 K. This device uses n+ - p+ double-gate SOI MOSFETs with a gate length (LG) of 0.19 micrometers and a gate oxide thickness (tox) around 9 nm. The channel doping concentration of this device is maintained as low as 1015 cm-3 even in the deep submicron gate length regime while maintaining short channel immunity. Therefore, the decreased phonon scattering due to the cryogenic operation causes a significant increase in mobility, which leads to smaller tpd than any other reported values for a given LG. Although the threshold voltage (Vth) increases with a decrease in temperature, we can adjust it for cryogenic operation by controlling tox and the SOI thicknesses (tSi).

Sugii, Toshihiro; Tanaka, Tetsu; Horie, Hiroshi; Suzuki, Kunihiro

1995-09-01

376

High-aperture cryogenic light microscopy.  

PubMed

We report here the development of instruments and protocols for carrying out high numerical aperture immersion light microscopy on cryogenic specimens. Imaging by this modality greatly increases the lifetimes of fluorescence probes, including those commonly used for protein localization studies, while retaining the ability to image the specimen with high fidelity and spatial resolution. The novel use of a cryogenic immersion fluid also minimizes the refractive index mismatch between the sample and lens, leading to a more efficient coupling of the light from the sample to the image forming system. This enhancement is applicable to both fluorescence and transmitted light microscopy techniques. The design concepts used for the cryogenic microscope can be applied to virtually any existing light-based microscopy technique. This prospect is particularly exciting in the context of 'super-resolution' techniques, where enhanced fluorescence lifetime probes are especially useful. Thus, using this new modality it is now possible to observe dynamic events in a live cell, and then rapidly vitrify the specimen at a specific time point prior to carrying out high-resolution imaging. The techniques described can be used in conjunction with other imaging modalities in correlated studies. We have also developed instrumentation to perform cryo-light imaging together with soft X-ray tomography on the same cryo-fixed specimen as a means of carrying out high content, quantifiable correlated imaging analyses. These methods are equally applicable to correlated light and electron microscopy of frozen biological objects. PMID:19566622

Le Gros, M A; McDermott, G; Uchida, M; Knoechel, C G; Larabell, C A

2009-07-01

377

Miniature thermo-electric cooled cryogenic pump  

DOEpatents

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

Keville, Robert F. (Valley Springs, CA)

1997-01-01

378

Miniature thermo-electric cooled cryogenic pump  

DOEpatents

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

Keville, R.F.

1997-11-18

379

Demonstration of Microsphere Insulation in Cryogenic Vessels  

NASA Astrophysics Data System (ADS)

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

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

2006-04-01

380

The acoustic effect of cryogenically treating trumpets  

NASA Astrophysics Data System (ADS)

The acoustic effect of cryogenically treating trumpets is investigated. Ten Vincent Bach Stradivarious B? trumpets are studied, half of which have been cryogenically treated. The trumpets were played by six players of varying proficiency, with sound samples being recorded directly to disk at a sampling rate of 44.1 kHz. Both the steady-state and initial transient portions of the audio samples are analyzed. When comparing the average power spectra of the treated trumpets to the untreated set, no repeatable, statistically independent differences are observed in the data. Differences observed in player-to-player and trumpet-to-trumpet comparisons overshadow any differences that may have been brought on due to the cryogenic treatment. Qualitatively, players established no clear preference between the treated and untreated trumpets regarding tone and playability, and could not differentiate between the two sets of instruments. All data was collected in a double blind fashion. The treatment itself is a three step process, involving an 8 hour linear cool down period, a 10 hour period of sustained exposure to -195°C (-300°F), and a 20-25 hour period of warming back to room temperature. [Work was completed with the support of Steinway & Sons Pianos and Selmer Musical Instruments.

Jones, Jesse; Rogers, Chris

2003-10-01

381

A Rapid Turnaround Cryogenic Detector Characterization System  

NASA Technical Reports Server (NTRS)

Upcoming major NASA missions such as the Einstein Inflation Probe and the Single Aperture Far-Infrared Observatory require arrays of detectors with thousands of elements, operating at temperatures near l00 mK and sensitive to wavelengths from approx. 100 microns to approx. 3 mm. Such detectors represent a substantial enabling technology for these missions, and must be demonstrated soon in order for them to proceed. In order to make rapid progress on detector development, the cryogenic testing cycle must be made convenient and quick. We have developed a cryogenic detector characterization system capable of testing superconducting detector arrays in formats up to 8 x 32, read out by SQUID multiplexers. The system relies on the cooling of a two-stage adiabatic demagnetization refrigerator immersed in a liquid helium bath. This approach permits a detector to be cooled from 300K to 50 mK in about 4 hours, so that a test cycle begun in the morning will be over by the end of the day. Tine system is modular, with two identical immersible units, so that while one unit is cooling, the second can be reconfigured for the next battery of tests. We describe the design, construction, and performance of this cryogenic detector testing facility.

Benford, Dominic j.; Dipirro, Michael J.; Forgione, Joshua B.; Jackson, Clifton E.; Jackson, Michael L.; Kogut, Al; Moseley, S. Harvey; Shirron, Peter J.

2004-01-01

382

Design Tool for Cryogenic Thermal Insulation Systems  

SciTech Connect

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

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

2008-01-01

383

Safety Aspects of Big Cryogenic Systems Design  

NASA Astrophysics Data System (ADS)

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

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

2010-04-01

384

Performance of cryogenically treated tungsten carbide tools in milling operations  

Microsoft Academic Search

This paper describes a study on the effects of cryogenic treatment of tungsten carbide. Cryogenic treatment has been acknowledged\\u000a by some as a means of extending the tool life of many cutting tool materials, but little is known about the mechanism behind\\u000a it. Thus far, the only few detailed studies conducted pertain to the cryogenic treatment of tool steels. However,

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

2007-01-01

385

Development of cryogenic instruments and equipment for SSC magnet cryogenic tests at the MTL  

SciTech Connect

The Magnet Test Laboratory (MTL) will test a considerable portion of the total SSC superconducting magnet production in order to control the manufacturing process and verify magnet performance requirements. With ten cryogenic test stands, MTL is capable of housing tests of 30 dipoles and 5 quadrupoles per month. For further understanding and improving the performance of the SSC magnets, there will be two R&D test stands for extensively instruments were allocated and installed inside the prototype and first production magnets, as well as in the feed and end cans. A data acquisition and control system is developed. A comprehensive cryogenic system (including refrigerator, cryogenic distribution box and, feed/end cans), vapor-cooled power leads, anti-cryostats (warm bore), and other associated systems, have been designed, developed and tested. This paper will briefly discuss the progress to date.

Shu, Q.S.; Coles, M.; Dorman, R.; Franclin, C.; Fuzesy, R.; Gabert, G.; Hatfield, D.; Syromyatnikov, I.; Tompkins, J.; Trekell, R.; Weisend, J.; Zolotov, A.

1993-05-01

386

Standard for Inert Cryogenic Liquid Usage in the Laboratory Page 1 of 4 Standard for Inert Cryogenic Liquid Usage in the Laboratory  

E-print Network

Cryogenic Liquid Usage in the Laboratory Page 1 of 4 March 2009 Standard for Inert Cryogenic Liquid Usage in the Laboratory In University workplaces, the storage, handling and dispensing of cryogenic liquids (e.g. liquid-up. Appropriate controls must be implemented wherever cryogenics are in use. This standard outlines some general

Chan, Hue Sun

387

Demonstration of an ultracold micro-optomechanical oscillator in a cryogenic cavity  

E-print Network

Preparing and manipulating quantum states of mechanical resonators is a highly interdisciplinary undertaking that now receives enormous interest for its far-reaching potential in fundamental and applied science. Up to now, only nanoscale mechanical devices achieved operation close to the quantum regime. We report a new micro-optomechanical resonator that is laser cooled to a level of 30 thermal quanta. This is equivalent to the best nanomechanical devices, however, with a mass more than four orders of magnitude larger (43 ng versus 1 pg) and at more than two orders of magnitude higher environment temperature (5 K versus 30 mK). Despite the large laser-added cooling factor of 4,000 and the cryogenic environment, our cooling performance is not limited by residual absorption effects. These results pave the way for the preparation of 100-um scale objects in the quantum regime. Possible applications range from quantum-limited optomechanical sensing devices to macroscopic tests of quantum physics.

Simon Groeblacher; Jared B. Hertzberg; Michael R. Vanner; Garrett D. Cole; Sylvain Gigan; K. C. Schwab; Markus Aspelmeyer

2009-01-13

388

Quadratic optomechanics in a cryogenic membrane-in-the-middle system  

E-print Network

Optomechanical experiments in the quantum regime have mostly been limited to the study of Gaussian states. This limitation is largely due to the linearity of the optomechanical coupling that is realized in most devices. In contrast, theoretical proposals show that non-Gaussian states and other striking quantum phenomena (such as quantum jumps between phonon number eigenstates) can be observed in optomechanical systems with large nonlinear coupling, provided that they operate in the resolved sideband regime, with very low damping, and in a sufficiently cold environment. Here we describe a device that meets these requirements. Specifically, we demonstrate a cryogenic, resolved sideband membrane-in-the-middle device with large quadratic optomechanical coupling. We present a thorough characterization of the classical dynamics that result from the quadratic coupling and find that these results agree with a simple model. We also use the quadratic coupling to monitor fluctuations of the intracavity laser power, in a...

Lee, Donghun; Mason, David; Shkarin, Alexey B; Hoch, Scott W; Harris, Jack G E

2014-01-01

389

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

SciTech Connect

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

J.K. Sekutowicz, P. Kneisel

2009-05-01

390

Daydreaming Devices  

E-print Network

Daydreaming Devices is a project on aspects of daydream and the design of convertible furniture within the context of art. This thesis addresses the concepts and the design of two daydreaming devices developed during my ...

Da Ponte, Ana Sofia Lopes

2008-01-01

391

Cryopumping in Cryogenic Insulations for a Reusable Launch Vehicle  

NASA Technical Reports Server (NTRS)

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

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

2003-01-01

392

Commissioning the cryogenic system of the first LHC sector  

SciTech Connect

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

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

2007-12-01

393

Cryogenic optical tests of a lightweight HIP beryllium mirror  

NASA Technical Reports Server (NTRS)

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

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

1989-01-01

394

Beyond the Large Hadron Collider: a first look at cryogenics for CERN future circular colliders  

E-print Network

Following the first experimental discoveries at the Large Hadron Collider (LHC) and the recent update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. The study, conducted with the collaborative participation of interested institutes world-wide, considers several options for very high energy hadron-hadron, electron-positron and hadron-electron colliders to be installed in a quasi-circular underground tunnel in the Geneva basin, with a circumference of 80 km to 100 km. All these machines would make intensive use of advanced superconducting devices, i.e. high-field bending and focusing magnets and/or accelerating RF cavities, thus requiring large helium cryogenic systems operating at 4.5 K or below. Based on preliminary sets of parameters and layouts for the particle colliders under study, we discuss the main challenges of their cryogenic systems and present first estimates of the cryogenic refrigeration capacities req...

Lebrun, Ph

2014-01-01

395

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

NASA Astrophysics Data System (ADS)

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

Nakasako, Masayoshi; Takayama, Yuki; Oroguchi, Tomotaka; Sekiguchi, Yuki; Kobayashi, Amane; Shirahama, Keiya; Yamamoto, Masaki; Hikima, Takaaki; Yonekura, Koji; Maki-Yonekura, Saori; Kohmura, Yoshiki; Inubushi, Yuichi; Takahashi, Yukio; Suzuki, Akihiro; Matsunaga, Sachihiro; Inui, Yayoi; Tono, Kensuke; Kameshima, Takashi; Joti, Yasumasa; Hoshi, Takahiko

2013-09-01

396

Cryogenic High-Frequency Readout and Control Platform for Spin Qubits  

E-print Network

We have developed a cryogenic platform for the control and readout of spin qubits that comprises a high density of dc and radio frequency sample interconnects based on a set of coupled printed circuit boards. The modular setup incorporates 24 filtered dc lines, 14 control and readout lines with bandwidth from dc to above 6 GHz, and 2 microwave connections for excitation to 40 GHz. We report the performance of this platform, including signal integrity and crosstalk measurements and discuss design criteria for constructing sample interconnect technology needed for multi-qubit devices.

J. I. Colless; D. J. Reilly

2011-11-28

397

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

DOEpatents

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

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

1992-01-01

398

An Overview of NASA's In-Space Cryogenic Propellant Management Technologies  

NASA Technical Reports Server (NTRS)

Future mission planning within NASA continues to include cryogenic propellants for in space transportation, with mission durations ranging from days to years. Between 1995 and the present, NASA has pursued a diversified program of ground-based testing to prepare the various technologies associated with in-space cryogenic fluid management (CFM) for implementation. CFM technology areas being addressed include passive insulation, zero gravity pressure control, zero gravity mass gauging, capillary liquid acquisition devices, and zero boiloff storage. NASA CFM technologies are planned, coordinated, and implemented through the Cryogenic Technology Working Group which is comprised of representatives from the various NASA Centers as well as the National Institute of Standards and Technologies (NIST) and, on selected occasions, the Air Force. An overview of the NASA program and Marshall Space Flight Center (MSFC) roles, accomplishments, and near-term activities are presented herein. Basic CFM technology areas being addressed include passive insulation, zero gravity pressure control, zero gravity mass gauging, capillary liquid acquisition devices, and zero boiloff storage. Recent MSFC accomplishments include: the large scale demonstration of a high performance variable density multilayer insulation (MLI) that reduced the boiloff by about half that of standard MLI; utilization of a foam substrate under MLI to eliminate the need for a helium purge bag system; demonstrations of both spray-bar and axial-jet mixer concepts for zero gravity pressure control; and sub-scale testing that verified an optical sensor concept for measuring liquid hydrogen mass in zero gravity. In response to missions requiring cryogenic propellant storage durations on the order of years, a cooperative effort by NASA's Ames Research Center, Glenn Research Center, and MSFC has been implemented to develop and demonstrate zero boiloff concepts for in-space storage of cryogenic propellants. An MSFC contribution to this cooperative effort is a large-scale demonstration of the integrated operation of passive insulation, destratification/pressure control, and cryocooler (commercial unit) subsystems to achieve zero boiloff storage of liquid hydrogen. Testing is expected during the Summer of 2001.

Tucker, Stephen; Hastings, Leon; Haynes, Davy (Technical Monitor)

2001-01-01

399

The LUCIFER MOS: a full cryogenic mask handling unit for a near-infrared multi-object spectrograph  

NASA Astrophysics Data System (ADS)

The LUCIFER-MOS unit is the full cryogenic mask-exchange unit for the near-infrared multi-object spectrograph LUCIFER at the Large Binocular Telescope. We present the design and functionality of this unique device. In LUCIFER the masks are stored, handled, and placed in the focal plane under cryogenic conditions at all times, resulting in very low thermal background emission from the masks during observations. All mask manipulations are done by a novel cryogenic mask handling robot that can individually address up to 33 fixed and user-provided masks and place them in the focal plane with high accuracy. A complete mask exchange cycle is done in less than five minutes and can be run in every instrument position and state reducing instrument setup time during science observations to a minimum. Exchange of old and new MOS masks is likewise done under cryogenic conditions using a unique exchange drive mechanism and two auxiliary cryostats that attach to the main instrument cryostat.

Buschkamp, Peter; Hofmann, Reiner; Gemperlein, Hans; Polsterer, Kai; Ageorges, Nancy; Eisenhauer, Frank; Lederer, Reinhard; Honsberg, Mathias; Haug, Marcus; Eibl, Johann; Seifert, Walter; Genzel, Reinhard

2010-07-01

400

Cryogenic gas disconnect joints used in cryogenic accelerator cold-gas distribution systems  

Microsoft Academic Search

Demountable gas disconnect joints are the preferred choice for assembly of cryogenic (20 K) helium gas manifolding systems used with linear accelerators being developed at Los Alamos. The joints, which are used to distribute helium refrigerant gas at pressures as high as 450 psi, must also be capable of passing helium leak tests with a maximum leak rate of 5×10-7

N. G. Wilson; C. Bridgman; R. J. Grieggs

1991-01-01

401

The development of a cryogenic over-pressure pump  

NASA Astrophysics Data System (ADS)

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

Alvarez, M.; Cease, H.; Flaugher, B.; Flores, R.; Garcia, J.; Lathrop, A.; Ruiz, F.

2014-01-01

402

What is the future of cryogenic fluid technology?  

Microsoft Academic Search

The general lack of technology development in the field of cryogenic fluid management (CFM) has led to continued use of obsolete, overweight, supercritical cryogenic fuels storage by spacecraft and their launch systems. CFM encompasses thermal and pressure control of liquid storage; the pressurization, acquisition, and subcooling of liquid supply; tank chilldowns for liquid transfer; slosh and dumping during fuel handling;

William J. Bailey

1991-01-01

403

Cryogenic dry etching for high aspect ratio microstructures  

Microsoft Academic Search

Cryogenic reactive ion etching (RIE) has been used to fabricate microstructures. The cryogenic system has a cathode stage that is temperature controlled from 0 to -140°C. A magnetic field and a narrow gap between electrodes are introduced to increase plasma density. The etching behavior of silicon and polyimide film has been investigated. Directional etching was achieved at low temperature. The

Kenji Murakami; Yuji Wakabayashi; Kazuyuki Minami; Masayoshi Esashi

1993-01-01

404

OPEN LOOP OPTIMIZATION OF LARGE SCALE CRYOGENIC PLANTS  

Microsoft Academic Search

In this work, we have performed the open loop dynamic optimization of a large-scale cryogenic plant, with rigorous process models. This model includes cryogenic heat exchangers, high-pressure separation tank and distillation columns. They comprise differential energy and mass balances; hydraulic correlations and rigorous thermodynamic predictions for equilibrium calculations in main units. Special attention has been devoted to countercurrent heat exchangers,

M. A. Rodríguez; J. A. Bandoni; M. S. Diaz

405

Mathematical modeling and simulation of cryogenic tunnel freezers  

Microsoft Academic Search

Modern food industries employ either mechanical or cryogenic methods for freezing products. A wealth of literature is available on design, implementation and optimization of mechanical freezing systems in the food industry. Cryogenic freezing is a relatively new technology for the food industry and there is a need for developing mathematical models to characterize this technology. Our focus here is to

Nazrul I. Shaikh; Vittal Prabhu

2007-01-01

406

Superconducting Meissner effect bearings for cryogenic turbomachines, phase 2  

Microsoft Academic Search

This is the final report of a Phase 2 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. The cryocoolers are designed to cool sensors on satellites. Existing gas bearings for this application run in a relatively warm state. The heat loss from the

Javier A. Valenzuela; Jerry L. Martin

1994-01-01

407

Cryogenic Scan Mechanism for Fourier Transform Spectrometer  

NASA Technical Reports Server (NTRS)

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

Brasunas, John C.; Francis, John L.

2011-01-01

408

Automatic control of cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

Inadequate Reynolds number similarity in testing of scaled models affects the quality of aerodynamic data from wind tunnels. This is due to scale effects of boundary-layer shock wave interaction which is likely to be severe at transonic speeds. The idea of operation of wind tunnels using test gas cooled to cryogenic temperatures has yielded a quantrum jump in the ability to realize full scale Reynolds number flow similarity in small transonic tunnels. In such tunnels, the basic flow control problem consists of obtaining and maintaining the desired test section flow parameters. Mach number, Reynolds number, and dynamic pressure are the three flow parameters that are usually required to be kept constant during the period of model aerodynamic data acquisition. The series of activity involved in modeling, control law development, mechanization of the control laws on a microcomputer, and the performance of a globally stable automatic control system for the 0.3-m Transonic Cryogenic Tunnel (TCT) are discussed. A lumped multi-variable nonlinear dynamic model of the cryogenic tunnel, generation of a set of linear control laws for small perturbation, and nonlinear control strategy for large set point changes including tunnel trajectory control are described. The details of mechanization of the control laws on a 16 bit microcomputer system, the software features, operator interface, the display and safety are discussed. The controller is shown to provide globally stable and reliable temperature control to + or - 0.2 K, pressure to + or - 0.07 psi and Mach number to + or - 0.002 of the set point value. This performance is obtained both during large set point commands as for a tunnel cooldown, and during aerodynamic data acquisition with intrusive activity like geometrical changes in the test section such as angle of attack changes, drag rake movements, wall adaptation and sidewall boundary-layer removal. Feasibility of the use of an automatic Reynolds number control mode with fixed Mach number control is demonstrated.

Balakrishna, S.

1989-01-01

409

CESAR: Cryogenic Electronics for Space Applications  

NASA Astrophysics Data System (ADS)

Ultra-low temperature sensors provide unprecedented performances in X-ray and far infrared astronomy by taking advantage of physical properties of matter close to absolute zero. CESAR is an FP7 funded project started in December 2010, that gathers six European laboratories around the development of high performances cryogenic electronics. The goal of the project is to provide far-IR, X-ray and magnetic sensors with signal-processing capabilities at the heart of the detectors. We present the major steps that constitute the CESAR work, and the main results achieved so far.

Revéret, V.; de la Broïse, X.; Fermon, C.; Pannetier-Lecoeur, M.; Pigot, C.; Rodriguez, L.; Sauvageot, J.-L.; Jin, Y.; Marnieros, S.; Bouchier, D.; Putzeys, J.; Long, Y.; Kiss, C.; Kiraly, S.; Barbera, M.; Lo Cicero, U.; Brown, P.; Carr, C.; Whiteside, B.

2014-08-01

410

Two phase pumping of cryogenic propellants  

NASA Technical Reports Server (NTRS)

Two-phase cryogenic propellant pumping techniques developed during the past 5 years are discussed. During this period the theory of two-phase pumping of hydrogen was developed into an operational technique that can result in significant benefits to space vehicle propulsion systems. Using two-phase pumping techniques, zero LH2 tank net positive suction head (NPSH) was demonstrated on turbopump and rocket engine firings, and limited experimental results show that two-phase pumping of liquid oxygen is feasible. Design techniques were developed for improving the two-phase pumping capability of inducers.

Stinson, H. P.; Gross, L. A.

1972-01-01

411

Pressure transducer and system for cryogenic environments  

NASA Technical Reports Server (NTRS)

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

Chapman, John J. (inventor)

1992-01-01

412

Piezoresistive silicon pressure sensors in cryogenic environment  

NASA Technical Reports Server (NTRS)

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

Kahng, Seun K.; Chapman, John J.

1989-01-01

413

Increasing the Cryogenic Toughness of Steels  

NASA Technical Reports Server (NTRS)

Grain-refining heat treatments increase toughness without substantial strength loss. Five alloys selected for study, all at or near technological limit. Results showed clearly grain sizes of these alloys refined by such heat treatments and grain refinement results in large improvement in toughness without substantial loss in strength. Best improvements seen in HP-9-4-20 Steel, at low-strength end of technological limit, and in Maraging 200, at high-strength end. These alloys, in grain refined condition, considered for model applications in high-Reynolds-number cryogenic wind tunnels.

Rush, H. F.

1986-01-01

414

Simple Spreadsheet Thermal Models for Cryogenic Applications  

NASA Technical Reports Server (NTRS)

Self consistent circuit analog thermal models that can be run in commercial spreadsheet programs on personal computers have been created to calculate the cooldown and steady state performance of cryogen cooled Dewars. The models include temperature dependent conduction and radiation effects. The outputs of the models provide temperature distribution and Dewar performance information. these models have been used to analyze the SIRTF Telescope Test Facility (STTF). The facility has been brought on line for its first user, the Infrared Telescope Technology Testbed (ITTT), for the Space Infrared Telescope Facility (SIRTF) at JPL. The model algorithm as well as a comparison between the models' predictions and actual performance of this facility will be presented.

Nash, Alfred

1995-01-01

415

SPICA sub-Kelvin cryogenic chains  

NASA Astrophysics Data System (ADS)

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

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

2012-04-01

416

Bulk solid dielectric for cryogenic cables  

NASA Astrophysics Data System (ADS)

This work investigates a number of bulk solid dielectric approaches applicable to both superconducting and cryoresistive cables, including solidification of ambient temperature dielectric fluids as well as conventional bulk solid dielectrics. The initial effort culminated with the successful testing for 20 h of 20 m of XLPE cable, in liquid helium at 4.2 K, preceded by a 30-day test in liquid nitrogen (77 K), both at four times rated voltage for comparable conventional cable. Thus, bulk solid cryogenic dielectric cables emerge not only as a feasible alternative to laminar insulated cryocables, but, potentially, as a superior form.

Bahder, G.; Rabinowitz, M.; Sosnowski, M.

417

Deep Space Network, Cryogenic HEMT LNAs  

NASA Technical Reports Server (NTRS)

Exploration of the Solar System with automated spacecraft that are more than ten astronomical units (1 AU = 149,597,870.691 km) from earth requires very large antennae employing extremely sensitive receivers. A key figure of merit in the specification of the spacecraft-to-earth telecommunications link is the ratio of the antenna gain to operatio nal noise temperature (G/Top) of the system. The Deep Space Network (DSN) receivers are cryogenic, low-noise amplifiers (LNAs) which addres s the need to maintain Top as low as technology permits. Historicall y, the extra-ordinarily sensitive receive systems operated by the DSN have required ctyogenically cooled, ruby masers, operating at a physi cal temperature near the boiling point of helium, as the LNA. Althoug h masers continue to be used today, they are hand crafted at JPL and expensive to manufacture and maintain. Recent advances in the developm ent of indium phosphide (InP) based high electron mobility transistor s (HEMTs) combined with cryogenic cooling near the boiling point of h ydrogen have made this alternate technology comparable with and a fraction of the cost of maser technology. InP HEMT LNA modules are demons trating noise temperatures less than ten times the quantum noise limi t (10hf/k) from 1 to 100 GHz. To date, the lowest noise LNA modules developed for the DSN have demonstrated noise temperatures of 3.5 K and 8.5 K at 8.5 K at 32 GHz, respectively. Front-end receiver packages employing these modules have demonstrated operating system noise temperatures of 17 K at 8.4 GHz (on a 70m antenna at zenith) and 39 K at 3 2 GHz (on a 34m antenna at zenith). The development and demonstration of cryogenic, InP HEMT based front-end amplifiers for the DSN requir es accurate component and module characterization, and modeling from 1 to 100 GHz at physical temperatures down to 12 K. The characterizati on and modeling begins with the HEMT chip, proceeds to the multi-stag e HEMT LNA module, and culminates with the complete front-end cryogenic receiver package for the antenna. This presentation will provide a n overview of this development process. Examples will be shown for de vices, LNA modules, front-end receiver packages, antennae employing these packages and the improvements to the down-link capacity.

Bautista, J. Javier

2006-01-01

418

Cryogenic system for ITER CS model coil  

SciTech Connect

A 5-kW/4.5-K helium refrigerator has been developed, which will be used for the test of ITER Central Solenoid Model Coil that is under fabrication by an international collaboration under the framework of the ITER Engineering Design Activity. Its acceptance test was recently finished and its specified refrigeration power of 5 kW with a surplus liquefaction rate of 114 1/h was demonstrated. A major feature of the refrigerator is that newly developed components, such as helium compressor and turbo-expander, are adopted in its simple refrigeration process in order that the results will be transferred to the ITER helium cryogenic system.

Kato, T.; Hamada, K.; Kawano, K.; Hiyama, T. [JAERI, Naka Fusion Research Establishment, Nada-machi, Nada-gun, Ibaraki-ken (Japan)] [and others

1996-12-31

419

Infrared filters for cryogenic millimeterwave receivers  

NASA Astrophysics Data System (ADS)

Filters are required to block infrared radiation from the low temperature regions of cryogenic receivers to reduce thermal loading and temperature gradients. The design and analysis of PTFE filters mounted on the radiation shield of a closed-cycle Joule-Thompson 4 K refrigerator is described. Calculations of the thermal transmission and emission of the filters are compared with measurements. It was found that the filters were not as effective as expected since the heat sinking of the material to the radiation shield was poor, but the overall heat load was less than anticipated since a thermal gradient developed across the polystyrene foam vacuum window, reducing its infrared emission.

Lamb, James W.

1993-05-01

420

Physical understanding of cryogenic implant benefits for electrical junction stability  

SciTech Connect

We investigate the effect of cryogenic temperature implants on electrical junction stability for ultra shallow junction applications for sub-32 nm technology nodes and beyond. A comprehensive study was conducted to gain physical understanding of the impact of cryogenic temperature implants on dopant-defect interactions. Carborane (C{sub 2}B{sub 10}H{sub 12}) molecule, a potential alternative to monomer boron was implanted in carbon preamorphized silicon substrates at cryogenic implant temperatures. Results indicate implants at cryogenic temperatures increase dopant activation with reduced diffusion, resulting in lower sheet resistance for a lower junction depth. Further, this study emphasizes the benefits of co-implants performed at cryogenic temperatures as alternative to traditional preamorphizing implants.

Adeni Khaja, Fareen; Colombeau, Benjamin; Thanigaivelan, Thirumal; Ramappa, Deepak; Henry, Todd [Applied Materials-Varian Semiconductor Equipment, 35 Dory Road, Gloucester, Massachusetts 01930 (United States)

2012-03-12

421

Cryogenic Insulation Bondline Studies for Reusable Launch Vehicles  

NASA Technical Reports Server (NTRS)

Cryogenic insulations bonded to metallic substrates were characterized under simulated mission conditions representative for a reusable launch vehicle. The combined thermal and mechanical test consisted of 50 to a 100 cycles. These combined thermal and mechanical cycles simulated flight missions with temperatures ranging from -423 F to 450 F and a maximum mechanical tension load ranging from 20,000 lbs. to 97,650 lbs. The combined thermal and mechanical (uniaxial tension) test apparatus (1 ft. by 2 ft. Test Apparatus) developed at the NASA Langley Research Center, was used to perform cyclic tests on cryogenic insulations bonded to tank wall substrates. No visual delamination or degradation was observed in the cryogenic insulation-to-metallic substrate bondline or butt joints between cryogenic insulation panels. In addition, after cyclic testing was performed, residual property results from tension-pull and closed-cell content tests of the cryogenic insulations indicated a decrease in the bondline strength and closed-cell content.

Johnson, T. F.; Weiser, E. S.; Duong, P. G.

2003-01-01

422

Numerical simulation for the temperature environment of cryogenic pump  

NASA Astrophysics Data System (ADS)

To improve performance and design of the cryogenic pump, analyze and solve the pump fault, and ensure the reliability of design and operating, it is highly necessary to understand the cryogenic pump temperature profile. Regarding horizontal single cryogenic centrifugal pump as the studied object, the flow field and structural heat transfer is calculated and analyzed. Based on reasonable boundary condition, three dimensional steady state of the pump mesh model is calculated by finite-element method with the software of Fluent, the fluid pressure field and the whole structural temperature profile is obtained. The structural temperature profile by finite-element heat transfer calculation indicates that: in the operating range of the cryogenic pump, the pumping cryogenic liquid is unable to vaporize at the room temperature, and the low temperature area is unable to interfere with the gear case in normal operation.

Li, X. X.

2012-11-01

423

Experimental investigation of cryogenic oscillating heat pipes  

PubMed Central

A novel cryogenic heat pipe, oscillating heat pipe (OHP), which consists of an 4 × 18.5 cm evaporator, a 6 × 18.5 cm condenser, and 10 cm length of adiabatic section, has been developed and experimental characterization conducted. Experimental results show that the maximum heat transport capability of the OHP reached 380W with average temperature difference of 49 °C between the evaporator and condenser when the cryogenic OHP was charged with liquid nitrogen at 48% (v/v) and operated in a horizontal direction. The thermal resistance decreased from 0.256 to 0.112 while the heat load increased from 22.5 to 321.8 W. When the OHP was operated at a steady state and an incremental heat load was added to it, the OHP operation changed from a steady state to an unsteady state until a new steady state was reached. This process can be divided into three regions: (I) unsteady state; (II) transient state; and (III) new steady state. In the steady state, the amplitude of temperature change in the evaporator is smaller than that of the condenser while the temperature response keeps the same frequency both in the evaporator and the condenser. The experimental results also showed that the amplitude of temperature difference between the evaporator and the condenser decreased when the heat load increased. PMID:20585410

Jiao, A.J.; Ma, H.B.; Critser, J.K.

2010-01-01

424

Cryogenic current-in-plane tunneling apparatus.  

PubMed

We have designed and fabricated a cryogenic variable-temperature current-in-plane tunneling apparatus to measure the magnetoresistive properties of unpatterned magnetic tunnel junction wafers as a function of temperature. The wafer is mounted on the cold finger of a liquid helium continuous flow cryostat. The temperature can be continuously varied between 7 and 330 K. We describe the design and fabrication of the micromachined silicon probe head that comprises a comb of 20 measuring and 4 leveling probes. The measuring probes are typically 0.7 microm wide and 1.2 microm thick, with lengths of 10, 7, and 4 microm, and a pitch that varies from 1.5 to 30 microm. The leveling probes are used in conjunction with a tilt stage to adjust the parallelism between the comb and the sample wafer during the approach of the probe head. The probe head is mounted on a nonmagnetic x-y stage, which can access a 22x22 mm(2) area with a repeatability of approximately 1 microm. The first measurements taken at room and cryogenic temperatures are shown. PMID:19123574

Weiss, Nicolas; Drechsler, Ute; Despont, Michel; Parkin, Stuart S P

2008-12-01

425

Thermal Design of a Collapsible Cryogenic Vessel  

NASA Technical Reports Server (NTRS)

Strategic planning for human exploration missions to Mars has conclusively identified in-situ resource utilization (ISRU) as an enabling technology. Most mission scenarios include an ISRU plant to produce propellants for ascent from Mars as well as the production of backup reserves of water, oxygen, and process gases. Current mission scenarios call for an ISRU plant to be deployed and then produce and store the required propellants and life support reserves before the arrival of the first human mission. Reliable cryogenic propellant liquefaction and storage technologies for extended period missions are especially critical. This report examines the cryogenic storage problem for liquid oxygen produced by an ISRU plant for a human mission scenario. The analysis examines various hardware configurations including insulation types, packaging techniques, and required cryocoolers to minimize the initial launch mass to low Earth orbit. Results of the analyses indicate that high vacuum insulation systems requiring vacuum pressures below one millitorr will be required to minimize the 'initial launch mass into low Earth orbit even though the temperature on the surface of Mars is much lower than Earth.

Hegab, Hisham E.

2001-01-01

426

Aerogel beads as cryogenic thermal insulation system  

NASA Astrophysics Data System (ADS)

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 Corporation have a bulk density below 100 kilograms per cubic meter (kg/m3) and a mean particle diameter of 1 millimeter (mm). The apparent thermal conductivity values of the bulk material have been determined under steady-state conditions at boundary temperatures of approximately 293 and 77 kelvin (K) and at various cold vacuum pressures (CVP). Vacuum levels ranged from 10-5 torr to 760 torr. All test articles were made in a cylindrical configuration with a typical insulation thickness of 25 mm. Temperature profiles through the thickness of the test specimens were also measured. The results showed the performance of the aerogel beads was significantly better than the conventional materials in both soft-vacuum (1 to 10 torr) and no-vacuum (760 torr) ranges. Opacified aerogel beads performed better than perlite powder under high-vacuum conditions. Further studies for material optimization and system application are in progress.

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

2002-05-01

427

The cryogenic gas stopping cell of SHIPTRAP  

NASA Astrophysics Data System (ADS)

The overall efficiency of the Penning-trap mass spectrometer SHIPTRAP at GSI Darmstadt, employed for high-precision mass measurements of exotic nuclei in the mass region above fermium, is presently mostly limited by the stopping and extraction of fusion-evaporation products in the SHIPTRAP gas cell. To overcome this limitation a second-generation gas cell with increased stopping volume was designed. In addition, its operation at cryogenic temperatures leads to a higher gas density at a given pressure and an improved cleanliness of the helium buffer gas. Here, the results of experiments with a 219Rn recoil ion source are presented. An extraction efficiency of 74(3)% was obtained, a significant increase compared to the extraction efficiency of 30% of the present gas stopping cell operated at room temperature. The optimization of electric fields and other operating parameters at room as well as cryogenic temperatures is described in detail. Furthermore, the extraction time of 219Rn ions was determined for several operating parameters.

Droese, C.; Eliseev, S.; Blaum, K.; Block, M.; Herfurth, F.; Laatiaoui, M.; Lautenschläger, F.; Minaya Ramirez, E.; Schweikhard, L.; Simon, V. V.; Thirolf, P. G.

2014-11-01

428

Power control electronics for cryogenic instrumentation  

NASA Astrophysics Data System (ADS)

In order to achieve a high-efficiency high-density cryogenic instrumentation system, the power processing electronics should be placed in the cold environment along with the sensors and signal-processing electronics. The typical instrumentation system requires low voltage dc usually obtained from processing line frequency ac power. Switch-mode power conversion topologies such as forward, flyback, push-pull, and half-bridge are used for high-efficiency power processing using pulse-width modulation (PWM) or resonant control. This paper presents several PWM and multiresonant power control circuits, implemented using commercially available CMOS and BiCMOS integrated circuits, and their performance at liquid-nitrogen temperature (77 K) as compared to their room temperature (300 K) performance. The operation of integrated circuits at cryogenic temperatures results in an improved performance in terms of increased speed, reduced latch-up susceptibility, reduced leakage current, and reduced thermal noise. However, the switching noise increased at 77 K compared to 300 K. The power control circuits tested in the laboratory did successfully restart at 77 K.

Ray, Biswajit; Gerber, Scott S.; Patterson, Richard L.; Myers, Ira T.

1995-08-01

429

Fielding the NIF Cryogenic Ignition Target  

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 on the inside of a 2 millimeter diameter capsule positioned at the center of a 9 millimeter long by 5 millimeter diameter cylinder, called a hohlraum. The ice layer requires micrometer level accuracy and must be formed and maintained at temperatures below 19 K. At NIF shot time, the target must be positioned at the center of the NIF 10 meter diameter target chamber, aligned to the laser beam lines and held stable to less than 7 micrometers rms. We have completed the final design and are integrating the systems necessary to create, characterize and field the cryogenic target for ignition experiments. These designs, with emphasis on the challenges of fielding a precision cryogenic positioning system will be presented.

Malsbury, T; Haid, B; Gibson, C; Atkinson, D; Skulina, K; Klingmann, J; Atherton, J; Mapoles, E; Kozioziemski, B; Dzenitis, E

2008-02-28

430

Power control electronics for cryogenic instrumentation  

NASA Technical Reports Server (NTRS)

In order to achieve a high-efficiency high-density cryogenic instrumentation system, the power processing electronics should be placed in the cold environment along with the sensors and signal-processing electronics. The typical instrumentation system requires low voltage dc usually obtained from processing line frequency ac power. Switch-mode power conversion topologies such as forward, flyback, push-pull, and half-bridge are used for high-efficiency power processing using pulse-width modulation (PWM) or resonant control. This paper presents several PWM and multiresonant power control circuits, implemented using commercially available CMOS and BiCMOS integrated circuits, and their performance at liquid-nitrogen temperature (77 K) as compared to their room temperature (300 K) performance. The operation of integrated circuits at cryogenic temperatures results in an improved performance in terms of increased speed, reduced latch-up susceptibility, reduced leakage current, and reduced thermal noise. However, the switching noise increased at 77 K compared to 300 K. The power control circuits tested in the laboratory did successfully restart at 77 K.

Ray, Biswajit; Gerber, Scott S.; Patterson, Richard L.; Myers, Ira T.

1995-01-01

431

Test techniques for cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

Some of the testing techniques developed for transonic cryogenic tunnels are presented. Techniques are emphasized which required special development or were unique because of the opportunities offered by cryogenic operation. Measuring the static aerodynamic coefficients normally used to determine component efficiency is discussed. The first topic is testing of two dimensional airfoils at transonic Mach numbers and flight values of Reynolds number. Three dimensional tests of complete configurations and sidewall mounted wings are also described. Since flight Reynolds numbers are of interest, free transition must be allowed. A discussion is given of wind tunnel and model construction effects on transition location. Time dependent phenomena, fluid mechanics, and measurement techniques are examined. The time dependent, or unsteady, aerodynamic test techniques described include testing for flutter, buffet, and oscillating airfoil characteristics. In describing non-intrusive laser techniques, discussions are given regarding optical access, seeding, forward scatter lasers, two-spot lasers, and laser holography. Methods of detecting transition and separation are reported and a new type of skin friction balance is described.

Lawing, Pierce L.

1989-01-01

432

Cryogenic Insulation System for Soft Vacuum  

NASA Technical Reports Server (NTRS)

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 conductivity [k-value in milliwatt per meter-kelvin (mW/m-K)]. System k-values below 0.1 can be achieved for multilayer insulation operating at a vacuum level below 1 x 10(exp -4) torr. For fiberglass or powder operating below 1 x 10(exp -3) torr, k-values of about 2 are obtained. For foam and other materials at ambient pressure, k-values around 30 are typical. New industry and aerospace applications require a versatile, robust, low-cost thermal insulation with performance in the intermediate range. The target for the new composite insulation system is a k-value below 4.8 mW/m-K (R-30) at a soft vacuum level (from 1 to 10 torr) and boundary temperatures of approximately 77 and 293 kelvin (K). Many combinations of radiation shields, spacers, and composite materials were tested from high vacuum to ambient pressure using cryostat boiloff methods. Significant improvement over conventional systems in the soft vacuum range was demonstrated. The new layered composite insulation system was also shown to provide key benefits for high vacuum applications as well.

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

1999-01-01

433

Risk analysis of the ITER cryogenic system  

NASA Astrophysics Data System (ADS)

The reliability of the ITER tokamak will strongly depend on the safe operation of the cryogenic system. The objective of the performed risk analysis is to identify all the possible risks to personnel, equipment and environment resulting from cryogenic system failures that might accidentally occur within any phases of the machine operation, and that could not be eliminated by design. The applied methodology of the presented risk analysis is based on the Failure Mode and Effects Analysis. All the potential failure modes were analyzed to identify their possible effects and then to classify them according to their severity and probability of occurrence. The Pareto-Lorentz analysis has been used for ranking all the identified failures and determining the most credible incidents and scenarios. For the most credible scenarios numerical simulations of the helium outflows from the system have been performed, including analysis of the helium flow impact on the neighboring confinements. Conclusions concerning the system safe operation, remedial actions and mitigations of the most credible incidents have been formulated.

Chorowski, Maciej; Fydrych, Jaroslaw; Grabowski, Maciej; Serio, Luigi

2012-06-01

434

Electrochromic devices  

DOEpatents

An electrochromic device is disclosed having a selective ion transport layer which separates an electrochemically active material from an electrolyte containing a redox active material. The devices are particularly useful as large area architectural and automotive glazings due to there reduced back reaction.

Allemand, Pierre M. (Tucson, AZ); Grimes, Randall F. (Ann Arbor, MI); Ingle, Andrew R. (Tucson, AZ); Cronin, John P. (Tucson, AZ); Kennedy, Steve R. (Tuscon, AZ); Agrawal, Anoop (Tucson, AZ); Boulton, Jonathan M. (Tucson, AZ)

2001-01-01

435

Cryogenic Characterization and Testing of Magnetically-Actuated Microshutter Arrays for the James Webb Space Telescope  

NASA Technical Reports Server (NTRS)

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 (approximately 35 K) spectrographic astronomy measurements in the near-infrared region. Functioning as a focal plane object selection device, the MSA is a 2-D programmable aperture mask with fine resolution, high efficiency and high contrast. The MSA are close- packed silicon nitride shutters (cell size of 100 x 200 microns) patterned with a torsion flexure to allow opening to 90 degrees. A layer of magnetic material is deposited onto each shutter to permit magnetic actuation. Two electrodes are deposited, one onto each shutter and another onto the support structure side-wall, permitting electrostatic latching and 2-D addressing. New techniques were developed to test MSA under mission-similar conditions (8 K less than or equal to T less than 300K). The magnetic rotisserie has proven to be an excellent tool for rapid characterization of MSA. Tests conducted with the magnetic rotisserie method include accelerated cryogenic lifetesting of unpackaged 128 x 64 MSA and parallel measurement of the magneto-mechanical stiffness of shutters in pathfinder test samples containing multiple MSA designs. Lifetest results indicate a logarithmic failure rate out to approximately 10(exp 6) shutter actuations. These results have increased our understanding of failure mechanisms and provide a means to predict the overall reliability of MSA devices.

King, T. T.; Kletetschka, G.; Jah, M. A.; Li, M. J.; Jhabvala, M. D.; Wang, L. L.; Beamesderfer, M. A.; Kutyrev, A. S.; Silverberg, R. F.; Rapchun, D.; Schwinger, D. S.

2004-01-01

436

Effect of Cryogenic Treatment on Properties of Cr8Type Cold Work Die Steel  

Microsoft Academic Search

The effect of cryogenic treatment on the properties of Cr8-type cold work die steel was investigated. The results show that cryogenic treatment increases hardness by decreasing retained austenite, but the degree depends on the austenitizing temperature. When quenching at lower austenitizing temperature, the steel can obtain higher toughness by cryogenic treatment substituting conventional treatment process. Cryogenic time has little effect

Hong-xiao CHI; Dang-shen MA; Qi-long YONG; Li-zhi WU; Zhan-pu ZHANG; Yong-wei WANG

2010-01-01

437

CRYOGENICS AND ITS APPLICATION WITH REFERENCE TO SPICE GRINDING: A REVIEW  

Microsoft Academic Search

Cryogenics’ is the study of very low temperature and its application on different materials including biological products. Cryogenics has numerous applications in space science, electronics, automobiles, manufacturing industry, sports and musical instruments, biological science and agriculture etc. Cryogenic freezing finds pivotal application in food i.e. spices and condiments. Although there is a wide range of cryogens to produce the desired

S. Balasubramanian; Manoj Kumar Gupta; K. K. Singh

2011-01-01

438

Cryogenics and its Application with Reference to Spice Grinding: A Review  

Microsoft Academic Search

Cryogenics is the study of very low temperature and its application on different materials including biological products. Cryogenics has numerous applications in space science, electronics, automobiles, the manufacturing industry, sports and musical instruments, biological science and agriculture, etc. Cryogenic freezing finds pivotal application in food, that is, spices and condiments. Although there is a wide range of cryogens to produce

S. Balasubramanian; Manoj Kumar Gupta; K. K. Singh

2012-01-01

439

Advances in cryogenic engineering. Vols. 37A & 37B - Proceedings of the 1991 Cryogenic Engineering Conference, Univ. of Alabama, Huntsville, June 11-14, 1991  

NASA Technical Reports Server (NTRS)

The present volume on advances in cryogenic engineering discusses heat and mass transfer in helium, heat transfer in cryogenic fluids, thermoacoustic oscillations, and insulation. Attention is given to applications of superconductivity with reference to magnetic stability and coil protection, cryogenic techniques, and refrigeration for electronics and superconducting systems. Topics addressed include compressors, expanders, and pumps for liquid helium, magnetic refrigerators, pulse tube refrigerators, and cryocoolers. Also examined are properties of cryogenic fluids, cryogenic applications in transportion and space science and technology, and cryogenic instrumentation.

Fast, Ronald W. (editor)

1991-01-01

440

Study and design of cryogenic propellant acquisition systems. Volume 2: Supporting experimental program  

NASA Technical Reports Server (NTRS)

Areas of cryogenic fuel systems were identified where critical experimental information was needed either to define a design criteria or to establish the feasibility of a design concept or a critical aspect of a particular design. Such data requirements fell into three broad categories: (1) basic surface tension screen characteristics; (2) screen acquisition device fabrication problems; and (3) screen surface tension device operational failure modes. To explore these problems and to establish design criteria where possible, extensive laboratory or bench test scale experiments were conducted. In general, these proved to be quite successful and, in many instances, the test results were directly used in the system design analyses and development. In some cases, particularly those relating to operational-type problems, areas requiring future research were identified, especially screen heat transfer and vibrational effects.

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

1973-01-01

441

Cryogenics at the university of southampton: a review  

NASA Astrophysics Data System (ADS)

This Paper reviews the considerable breadth of activity in cryogenics across the campus of the University of Southampton. While this activity is focussed on the Institute of Cryogenics which was created in 1979, a very great deal of collaborative work is described involving the Departments of Chemistry and Physics in the Faculty of Science, the Departments of Aeronautics and Astronautics, Civil Engineering, Electrical Engineering, Electronics and Computer Science, and Mechanical Engineering in the Faculty of Engineering and Applied Science, and the Faculties of Mathematics and Medicine. The development of cryogenics from the early 1950s is described and traces the growing impact of the Southampton findings in cryogenic fluid mechanics on vapour cooled shields, dewar and cryostat design, storage instabilities in large tanks, carbon loaded multi-layer insulations, rotating helium at 3000 rev min - and cryosurgical probes. Current activity described includes the rapid expansion in work on high Tc superconductors, the development of cryogenic and frost proof concrete, boiling and condensation heat transfer in liquid nitrogen, magnetic separation, refrigerators, pipe freezing, cold electronics, cryogenic wind tunnels and mathematical modelling of cryogenic convection.

Scurlock, R. G.

442

Adhesive Bonding Characterization of Composite Joints for Cryogenic Usage  

NASA Technical Reports Server (NTRS)

The development of polymer composite cryogenic tanks is a critical step in creating the next generation of launch vehicles. Future reusable launch vehicles need to minimize the gross liftoff weight (GLOW). This weight reduction is possible due to the large reduction in weight that composite materials can provide over current aluminum technology. In addition to composite technology, adhesively bonded joints potentially have several benefits over mechanically fastened joints, such as weight savings and cryogenic fluid containment. Adhesively bonded joints may be used in several areas of these cryogenic tanks, such as in lobe-to-lobe joints (in a multi-lobe concept), skirt-to-tank joint, strut-to-tank joint, and for attaching stringers and ring frames. The bonds, and the tanks themselves, must be able to withstand liquid cryogenic fuel temperatures that they contain. However, the use of adhesively bonded composite joints at liquid oxygen and hydrogen temperatures is largely unknown and must be characterized. Lockheed Martin Space Systems Company, Michoud Operations performed coupon-level tests to determine effects of material selection, cure process parameters, substrate surface preparation, and other factors on the strength of these composite joints at cryogenic temperatures. This led to the selection of a material and process that would be suitable for a cryogenic tank. KEY WORDS: Composites, Adhesive Bonding, Cryogenics

Graf, Neil A.; Schieleit, Gregory F.; Biggs, Robert

2000-01-01

443

Improved Cryogenic Optical Test Capability at Marshall Space Flight Center's X-ray Cryogenic Test Facility  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center's X-ray & Cryogenic Test Facility (XRCF) has been performing optical wavefront testing and thermal structural deformation testing at subliquid nitrogen cryogenic temperatures since 1999. Recent modifications have been made to the facility in support of the James Webb Space Telescope (JWST) program. The test article envelope and the chamber's refrigeration capacity have both been increased. A new larger helium-cooled enclosure has been added to the existing enclosure increasing both the cross-sectional area and the length. This new enclosure is capable of supporting six JWST Primary Mirror Segment Assemblies. A second helium refrigeration system has been installed essentially doubling the cooling capacity available at the facility. Modifications have also been made to the optical instrumentation area. Improved access is now available for both the installation and operation of optical instrumentation outside the vacuum chamber. Chamber configuration, specifications, and performance data will be presented.

Kegley, Jeffrey; Haight, Harlan; Hogue, William; Carpenter, Jay; Siler, Richard; Wright, Ernie; Eng, Ron; Baker, Mark; McCracken, Jeff

2005-01-01

444

Comparison of cryogenic W band low noise amplifier based on different III-V HEMT foundry process and technologies  

NASA Astrophysics Data System (ADS)

We present the results of a development activity for cryogenic Low Noise Amplifiers based on HEMT technology for ground based and space-borne application. We have developed and realized two LNA design in W band, based on m-HEMT technology. MMIC chips have been manufactured by European laboratories and companies and assembled in test modules by our team. We compare performances with other technologies and manufacturers. LNA RF properties (noise figures, S-parameters) have been measured at room and cryogenic temperature and test results are reported in this paper. Performance are compared with those of state-of-the-art devices, as available in the literature. Strengths and improvements of this project are also discussed.

Valenziano, L.; Zannoni, M.; Mariotti, S.; Cremonini, A.; De Rosa, A.; Banfi, S.; Baó, A.; Gervasi, M.; Limiti, E.; Passerini, A.; Schiavone, F.

2014-07-01

445

Progress on the cryogenic system for the KAGRA cryogenic interferometric gravitational wave telescope  

NASA Astrophysics Data System (ADS)

KAGRA is a project to construct a cryogenic interferometric gravitational wave detector in Japan. Its mirrors and the lower parts of the suspension systems will be cooled to 20 K in order to reduce thermal noise, one of the fundamental noise sources. One of the key features of KAGRA?s cooling system is that it will keep the mirrors cooled without introducing vibration. This paper describes the current status of the design, manufacture and testing of the KAGRA cooling system.

Sakakibara, Yusuke; Akutsu, Tomotada; Chen, Dan; Khalaidovski, Aleksandr; Kimura, Nobuhiro; Koike, Shigeaki; Kume, Tatsuya; Kuroda, Kazuaki; Suzuki, Toshikazu; Tokoku, Chihiro; Yamamoto, Kazuhiro

2014-11-01

446

Effect of cryogenic treatment on distribution of residual stress in case carburized En 353 steel  

Microsoft Academic Search

The effect of cryogenic treatment on the distribution of residual stress in the case carburized steel (En 353) was studied using X-ray diffraction technique. Two types of cryogenic treatment: shallow cryogenic treatment (193K) and deep cryogenic treatment (77K) were adopted, as a supplement to conventional heat treatment. The amount of retained austenite in conventionally heat-treated, shallow cryogenically treated and deep

A. Bensely; S. Venkatesh; D. Mohan Lal; G. Nagarajan; A. Rajadurai; Krzysztof Junik

2008-01-01

447

Cryogenic system operating experience review for fusion applications  

SciTech Connect

This report presents a review of cryogenic system operating experiences, from particle accelerator, fusion experiment, space research, and other applications. Safety relevant operating experiences and accident information are discussed. Quantitative order-of-magnitude estimates of cryogenic component failure rates and accident initiating event frequencies are presented for use in risk assessment, reliability, and availability studies. Safety concerns with cryogenic systems are discussed, including ozone formation, effects of spills, and modeling spill behavior. This information should be useful to fusion system designers and safety analysts, such as the team working on the International Thermonuclear Experimental Reactor design.

Cadwallader, L.C.

1992-01-01

448

Spacecraft-borne long life cryogenic refrigeration: Status and trends  

NASA Technical Reports Server (NTRS)

The status of cryogenic refrigerator development intended for, or possibly applicable to, long life spacecraft-borne application is reviewed. Based on these efforts, the general development trends are identified. Using currently projected technology needs, the various trends are compared and evaluated. The linear drive, non-contacting bearing Stirling cycle refrigerator concept appears to be the best current approach that will meet the technology projection requirements for spacecraft-borne cryogenic refrigerators. However, a multiply redundant set of lightweight, moderate life, moderate reliability Stirling cycle cryogenic refrigerators using high-speed linear drive and sliding contact bearings may possibly suffice.

Johnson, A. L.

1983-01-01

449

Harmonic phase detector for phase locking of cryogenic terahertz oscillators  

NASA Astrophysics Data System (ADS)

We present a simple and effective way to phase lock terahertz cryogenic oscillators. Extreme nonlinearity of a superconductor-insulator-superconductor tunnel junction allows its implementation as a cryogenic high-harmonic phase detector (HPD), which is used both for mixing a terahertz oscillator signal with a microwave reference and for generating a phase error feedback signal that is directly applied to the oscillator for its phase locking. An integration of the HPD with a cryogenic flux-flow oscillator results in synchronization bandwidth as wide as 70 MHz (significantly exceeding conventional room-temperature system bandwidth), providing phase locking of 84% emitted power for 15 MHz oscillator linewidth.

Kalashnikov, Konstantin V.; Khudchenko, Andrey V.; Koshelets, Valery P.

2013-09-01

450

Thermohydrodynamic analysis of cryogenic liquid turbulent flow fluid film bearings  

NASA Technical Reports Server (NTRS)

A thermohydrodynamic analysis is presented and a computer code developed for prediction of the static and dynamic force response of hydrostatic journal bearings (HJB's), annular seals or damper bearing seals, and fixed arc pad bearings for cryogenic liquid applications. The study includes the most important flow characteristics found in cryogenic fluid film bearings such as flow turbulence, fluid inertia, liquid compressibility and thermal effects. The analysis and computational model devised allow the determination of the flow field in cryogenic fluid film bearings along with the dynamic force coefficients for rotor-bearing stability analysis.

Andres, Luis San

1993-01-01

451

Cryogenic grinding: an efficient method for recycling scrap rubber  

SciTech Connect

Cryogenic grinding represents an opportunity for expanding recycling capabilities to a broad range of compounds. Many materials that can be reduced to a powder by conventional coarse grinding can be reduced more efficiently by using a super-cold agent such as liquid nitrogen at -320/sup 0/F to embrittle plastic or rubber polymers before grinding. In addition, cryogenic grinding makes possible the size reduction of many materials that cannot be ground by conventional ambient grinding methods. Some experiences of cryogenic grinding in practice at United Tire and Rubber company, Limited, headquartered in Rexdale, Ontario, are noted. A schematic of such a system is shown.

Not Available

1980-06-01

452

Reusable cryogenic foam insulation for advanced aerospace vehicles  

NASA Technical Reports Server (NTRS)

Future high-speed aircraft and aerospace vehicles using cryogenic propellants will require an advanced reusable insulation system for the propellant tank structure. This cryogenic insulation system must be lightweight, structurally and thermally efficient, and capable of multiple reuse without cracking or degraded performance. This paper presents recent progress in the development of a reusable cryogenic foam insulation system having a maximum service temperature of 400 F. The system consists of preshaped, precut blocks of rigid polymethacrylimide foam insulation, wrapped with a high-temperature Kapton and aluminum foil vapor barrier which is adhesively bonded to the propellant tank wall.

Mcauliffe, Patrick S.; Taylor, Allan H.; Sparks, Larry L.; Dube, William P.

1991-01-01

453

Cost effective use of liquid nitrogen in cryogenic wind tunnels  

NASA Technical Reports Server (NTRS)

A method of reliquefying from 12 to 19% of the nitrogen exhaust gas from a cryogenic wind tunnel has been developed. Technical feasibility and cost effectiveness of the system depends on performance of an innovative positive displacement expander which requires scale model testing to confirm design studies. The existing cryogenic system at the 0.3-m transonic cryogenic tunnel has been surveyed and extensive upgrades proposed. Upgrades are generally cost effective and may be implemented immediately since they are based on established technology.

Mcintosh, Glen E.; Lombard, David S.; Martindale, David L.; Dunn, Robert P.

1987-01-01

454

Gripping device  

NASA Technical Reports Server (NTRS)

This invention relates to a gripping device, and more particularly to one with a large moment carrying capability for handling long workpieces of various diameters and which can be particularly used as an end effector on a robotic arm.

Parma, George F. (inventor)

1989-01-01

455

Device Performance  

SciTech Connect

In the Device Performance group, within the National Center for Photovoltaic's Measurements and Characterization Division, we measure the performance of PV cells and modules with respect to standard reporting conditions--defined as a reference temperature (25 C), total irradiance (1000 Wm-2), and spectral irradiance distribution (IEC standard 60904-3). Typically, these are ''global'' reference conditions, but we can measure with respect to any reference set. To determine device performance, we conduct two general categories of measurements: spectral responsivity (SR) and current versus voltage (I-V). We usually perform these measurements using standard procedures, but we develop new procedures when required by new technologies. We also serve as an independent facility for verifying device performance for the entire PV community. We help the PV community solve its special measurement problems, giving advice on solar simulation, instrumentation for I-V measurements, reference cells, measurement procedures, and anomalous results. And we collaborate with researchers to analyze devices and materials.

Not Available

2006-06-01

456

Cryogenic Undulator for a Table Top FEL  

NASA Astrophysics Data System (ADS)

A laser plasma accelerator is under development at the Max-Planck-Institut für Quantenoptik in Garching. This accelerator will be part of an X-ray table top FEL in the future. The FEL radiation will be produced with a small period in-vacuum undulator. The coercivity of the magnetic material has to be sufficiently high in order to avoid demagnetization due to electron losses. The best performance can be achieved with a cryogenic permanent magnet undulator design. (Nd0.2Pr0.8)2Fe14B magnets are suited for low temperatures since they do not suffer from a spin reorientation. A new (Nd0.2Pr0.8)2Fe14B material has been characterized at various temperatures and the results are presented. Based on this material a 20 period prototype with a period length of 9 mm and a magnetic gap of 2.5 mm is currently under construction.

Bahrdt, J.; Frentrup, W.; Gaupp, A.; Scheer, M.; Weingartner, R.; O'Shea, F.; Grüner, F.

2010-06-01

457

The LINC-NIRVANA cryogenic interferometric camera  

NASA Astrophysics Data System (ADS)

The LINC-NIRVANA instrument is a 1-2.5 micron Fizeau interferometric imager, which combines the light of the two 8.4 m mirrors of the Large Binocular Telescope on Mt. Graham in Arizona. The cryogenic camera forms the heart of the science channel of this instrument, delivering a 1 arcmin diameter field of view with 5 mas spatial resolution. The center 10x10 arcseconds, initially limited by the size of the 2048x2048 Hawaii-2 detector, are used for science observations. For simplicity, the camera has a fixed, F/32 optical path of the combined beams, leading to wavelength-dependent sampling. We describe the main components of the camera, as well as present the calculations of interferometric performance and the required opto-mechanical tolerances. We demonstrate that specially designed components can reach these specifications.

Bizenberger, Peter; Andersen, Dave; Baumeister, Harald; Beckmann, Udo; Diolaiti, Emiliano; Herbst, Tom M.; Laun, Werner; Mohr, Lars; Naranjo, Vianak; Straubmeier, Christian

2004-09-01

458

CIRRIS 1A cryogen system performance  

NASA Astrophysics Data System (ADS)

The Cryogenic InfraRed Radiance Instrumentation for Shuttle (CIRRIS 1A) instrument, successfully flown and operated on the Shuttle Discovery from 28 April to 6 May 1991, was designed to operate at supercritical helium temperatures. During flight, the focal plane temperature control and telescope contamination purge systems performed as designed and 36 hours of excellent data was obtained; however, the parasitic helium flow rate was higher than expected. This paper reviews thermal data obtained for the CIRRIS 1A cooling system during both ground and flight operations. The temperature control and purge systems are discussed, along with helium flow rates, dewar helium pressure, and thermal stratification. In addition, possible reasons for the high on-orbit parasitic flow rate are presented.

Vendell, E. W.; Morse, David E.; Landoch, Andrew

1993-01-01

459

A cryogenic multichannel electronically scanned pressure module  

NASA Technical Reports Server (NTRS)

Consideration is given to a cryogenic multichannel electronically scanned pressure (ESP) module developed and tested over an extended temperature span from -184 to +50 C and a pressure range of 0 to 5 psig. The ESP module consists of 32 pressure sensor dice, four analog 8 differential-input multiplexers, and an amplifier circuit, all of which are packaged in a physical volume of 2 x 1 x 5/8 in with 32 pressure and two reference ports. Maximum nonrepeatability is measured at 0.21 percent of full-scale output. The ESP modules have performed consistently well over 15 times over the above temperature range and continue to work without any sign of degradation. These sensors are also immune to repeated thermal shock tests over a temperature change of 220 C/sec.

Shams, Qamar A.; Fox, Robert L.; Adcock, Edward E.; Kahng, Seun K.

1992-01-01

460

Silicon single-crystal cryogenic optical resonator.  

PubMed

We report on the demonstration and characterization of a silicon optical resonator for laser frequency stabilization, operating in the deep cryogenic regime at temperatures as low as 1.5 K. Robust operation was achieved, with absolute frequency drift less than 20 Hz over 1 h. This stability allowed sensitive measurements of the resonator thermal expansion coefficient (?). We found that ?=4.6×10(-13)??K(-1) at 1.6 K. At 16.8 K ? vanishes, with a derivative equal to -6×10(-10)??K(-2). The temperature of the resonator was stabilized to a level below 10 ?K for averaging times longer than 20 s. The sensitivity of the resonator frequency to a variation of the laser power was also studied. The corresponding sensitivities and the expected Brownian noise indicate that this system should enable frequency stabilization of lasers at the low-10(-17) level. PMID:24876023

Wiens, Eugen; Chen, Qun-Feng; Ernsting, Ingo; Luckmann, Heiko; Rosowski, Ulrich; Nevsky, Alexander; Schiller, Stephan

2014-06-01