Now showing items 1-20 of 89

    • Heat Rejection Capacity in Miniature Thermoacoustic Expanders at Cryogenic Temperature 77 K 

      Hu, Zhimin; Roberts, T. (Georgia Institute of TechnologyICC Press, 2008-05)
      Miniaturized thermoacoustic expanders MTAEs are a new type of expander designed to improve the cooling efficiency of recuperative type cryocoolers without sacrificing their reliability and simplicity. Experimental studies ...
    • Experimental Study of Active Magnetic Regenerator (AMR) Composed of Spherical GdN 

      Hirayama, Y.; Okada, H.; Nakagawa, T.; Yamamoto, T. A.; Kusunose, T.; Numazawa, T.; Mastumoto, K.; Irie, T.; Nakamura, E. (Georgia Institute of TechnologyICC Press, 2008-05)
      An experimental study of an active magnetic regenerator (AMR) employing GdN was carried out. Spherical GdN material was synthesized by the hot isostatic pressing (HIP) method. The specific heat was measured and the ...
    • Concept of a Powerful Cryogen-Free Dilution Refrigerator with Separate 1 K Stage 

      Uhlig, Kurt (Georgia Institute of TechnologyICC Press, 2008-05)
      Helium-3,4 dilution refrigerators (DR) are the workhorses for ultralow temperature scientists. DRs can be continuously operated for unlimited periods of time, and compared to other cooling techniques offer high cooling ...
    • Numerical Modeling on Reciprocating Active Magnetic Refrigeration Regenerator at Room Temperature 

      Li, Jing; Numazawa, T.; Matsumoto, K.; Nakagome, H. (Georgia Institute of TechnologyICC Press, 2008-05)
      A 2-dimension porous media model has been constructed for Reciprocating Active Magnetic Refrigeration Regenerator (AMR). The 2-D model is solved using a fully implicit (in time and space) discretization of the 2-dimension ...
    • Cryocoolers for Microsatellite Military Applications 

      Pettyjohn, Erin (Georgia Institute of TechnologyICC Press, 2008-05)
      Space qualified cryocoolers have been extensively developed for large military and commercial satellite electro-optical (EO) infrared (IR) missions, but not so for microsatellites due to the complexity of the thermodynamics ...
    • Progress in the Development of the IXO 50 mK Sorption-ADR stage 

      Duval, J. M.; Luchier, N.; Duband, L.; Tirolien, T. (Georgia Institute of TechnologyICC Press, 2008-05)
      The nominal temperature of the new generations of detectors for the next space mission International X-ray Observatory (IXO) is expected to be around 50 mK. The coupling of a 3He cooler with an ADR provides an elegant ...
    • Thermal Storage Unit Using the Triple Point of Hydrogen 

      Charles, I.; Coynel, A.; Daniel, C. (Georgia Institute of TechnologyICC Press, 2008-05)
      The French space agency (CNES) has co-funded a Research and Technology program and CEA/SBT has developed a 14 K thermal storage unit using the triple point of hydrogen. The development unit is able to store 10 J at 14 K. ...
    • Performance Test of Pulse Tube Cooler with Integrated Circulator 

      Maddocks, J. R.; Maddocks, P.; Fay, M.; Helvensteijn, B. P. M.; Kashani, A. (Georgia Institute of TechnologyICC Press, 2008-05)
      To address the need for remote and broad area cooling using regenerative cryocoolers, Atlas Scientific is developing a lightweight, continuous-flow Integrated Circulator (IC) for installation on Pulse Tube Cryocoolers ...
    • Drive Electronics for Moving Magnet Type Linear Motor Compressor 

      Karunanithi, R.; Jacob, S.; Singh Gour, Abhay (Georgia Institute of TechnologyICC Press, 2008-05)
      An inexpensive drive circuit to operate a moving magnet type linear motor compressor up to 100 W power is described. It is a Pulse-Width Modulated (PWM-based) circuit with provisions to adjust the frequency, modulation ...
    • Performance and Mass vs. Operating Temperature for Pulse Tube and Stirling Cryocoolers 

      Ladner, D. R. (Georgia Institute of TechnologyICC Press, 2008-05)
      Single stage pulse tube and Stirling cryocooler data that were reported in the open literature during the past decade were analyzed to find mathematical scaling laws for estimating the required input power and mass, as ...
    • Demonstration of a Cryogenic Boil-Off Reduction System Employing an Actively Cooled Thermal Radiation Shield 

      Feller, J. R.; Plachta, D. W.; Mills, G.; McLean, C (Georgia Institute of TechnologyICC Press, 2008-05)
      NASA, under the Cryogenic Fluid Management (CFM) Project, in partnership with Ball Aerospace Technologies Corporation (BATC), conducted a reduced boil-off demonstration employing an actively cooled thermal radiation shield. ...
    • Reduction of Self Induced Vibration in Rotary Stirling Cycle Coolers 

      Bin-Nun, U. (Georgia Institute of TechnologyICC Press, 2008-05)
      Cryocooler is a major consideration in the design of IR imaging systems, especially when mounted on stabilized platforms with gimbals. The coolers in these types of applications induce forces and moments that interfere ...
    • Self-Induced Vibration of NGAS Space Pulse Tube Coolers 

      Colbert, R.; Nguyen, T.; Raab, J.; Tward, E. (Georgia Institute of TechnologyICC Press, 2008-05)
      Space cryocoolers are often used to cool the focal planes and optics of telescopes. Since telescope and focal plane jitter can affect the clarity of the image, space cryocoolers are designed for inherent low vibration. For ...
    • Design and Analysis of Power Controller for Moving Magnet Linear Motor Compressor 

      Jacob, S.; Sriram Prabhu, K.; Karunanithi, R.; Ramanarayanan, V. (Georgia Institute of TechnologyICC Press, 2008-05)
      Permanent magnet linear motors (PMLM) are widely used in the design of pulse tube cryocoolers. In this paper, we discuss the design and analysis of a power controller used to drive the dual opposing piston type motors used ...
    • In-Flight Performance of the HERSCHEL Sorption Coolers – One Year of Operation 

      Duband, L.; Ercolani, E.; Guillemet, L.; Sauvage, M.; Martignac, J.; Swinyard, B.; Griffin, D.; Jewell, C.; Collaudin, B. (Georgia Institute of TechnologyICC Press, 2008-05)
      HERSCHEL, the fourth ‘cornerstone’ mission in the ESA science program, was launched on 14 May 2009 from Kourou, French Guyana. With a 3.5 m Cassegrain telescope it is the largest space telescope ever launched. HERSCHEL is ...
    • Low Temperature Adsorption Versus Pore Size in Activated Carbons 

      Martins, D.; Catarino, I.; Lopes, D.; Esteves, I.; Mota, J. P.; Bonfait, G. (Georgia Institute of TechnologyICC Press, 2008-05)
      Activated carbons have been used for a long time at low temperature for cryogenic applications. The physisorption properties depend on the pore geometry and size: this feature can be used to optimize the carbon structure ...
    • Flight Cryogenic System for the Micro-X Sounding Rocket 

      Wikus, P.; Rutherford, J. M.; Trowbridge, S. N.; McCammon, D.; Adams, J. S.; Bandler, S. R.; Das, R.; Doriese, W. B.; Eckart, M. E.; Figueroa-Feliciano, E.; Kelley, R. L.; Kilbourne, C. A.; Leman, S. W.; Porter, F. S.; Sato, K. (Georgia Institute of TechnologyICC Press, 2008-05)
      The Micro-X Imaging X-ray Spectrometer is a sounding rocket payload slated for launch in 2011. An array of transition edge sensors will be used to obtain high resolution X-ray spectra of astronomical sources. An Adiabatic ...
    • Analysis of a Supercritical Hydrogen Liquefaction Cycle 

      Staats, W. L.; Smith, J. L. ,Jr.; Brisson, J. G. (Georgia Institute of TechnologyICC Press, 2008-05)
      A supercritical hydrogen liquefaction cycle is proposed and analyzed numerically. If hydrogen is to be used as an energy carrier, the efficiency of liquefaction will become increasingly important. By examining some ...
    • Cryocooler Prognostic Health Management System 

      Sandt , E.; Penswick , L.; Shah, A.; Dodson, C.; Roberts, T. (Georgia Institute of TechnologyICC Press, 2008-05)
      The use of cooled sensors in ever more complex, integrated applications has made determination of the cryocooler and related component “health or remaining reliable useful life” a critical factor in successfully meeting ...
    • Experimental Apparatus for Measuring the Performance of a Precooled Mixed Gas Joule Thomson Cryosurgical Probe 

      Skye, H. M.; Klein, S. A.; Nellis, G. F. (Georgia Institute of TechnologyICC Press, 2008-05)
      Cryosurgery is a technique for destroying undesirable tissue such as cancers using a freezing process. A previous paper referenced here describes the development of a thermodynamic modeling tool for a precooled Mixed Gas ...