Now showing items 1-20 of 89

    • Developments of 1-4 K Class Space Mechanical Coolers for New Generation Satellite Missions in JAXA 

      Shinozak, K.; Sugita, H.; Sato, Y.; Mitsuda, K.; Nakagawa, T.; Fujimoto, R.; Narasaki, K.; Kanao, K.; Tsunematsu, S.; Otsuka, K. (Georgia Institute of TechnologyICC Press, 2008-05)
      Mechanical coolers are a key enabling technology to utilize low temperature scientific instruments for the new generation of space science missions, such as the new X-ray astronomical satellite Astro-H, and the new infrared ...
    • A Study of a Miniature In-Line Pulse Tube Cryocooler 

      Sobol, S.; Katz, Y.; Grossman, G. (Georgia Institute of TechnologyICC Press, 2008-05)
      A miniature pulse tube cryocooler has been designed and tested in our laboratory. The main part of the cryocooler, consisting of an in-line assembly of aftercooler, regenerator, cold heat exchanger, buffer tube and hot ...
    • Impact of Small Regenerator Structural Flaws on the Performance of Miniature Pulse Tube Cryocoolers 

      Conrad, T. J.; Ghiaasiaan, S. M. (Seyed M.); Kirkconnell, Carl Scott; Crittenden, Thomas M. (Georgia Institute of TechnologyICC Press, 2008-05)
      Miniature cryocoolers are suitable for space applications and installation in portable devices. They can also be useful as final stages for applications where small cooling loads must be carried at temperatures lower than ...
    • 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 ...
    • Progress in the Development and Performance of a High Frequency 4 K Stirling-Type Pulse Tube Cryocooler 

      Bradley, P. E.; Radebaugh, R.; Garaway, I.; Gerecht, E. (Georgia Institute of TechnologyICC Press, 2008-05)
      Presently we are in the development process for a 4 K Stirling-type pulse tube cryocooler to support cooling requirements for a mobile THz detector system. In this paper we discuss the status of this development and the ...
    • 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 ...
    • 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 ...
    • 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 ...
    • Performance of a Stirling-Type Pulse Tube Cooler for High Efficiency Operation at 100 Hz. 

      Wang, Xiaotao; Dai, Wei; Hu, Jianying; Luo, Ercang; Zhou, Yuan (Georgia Institute of TechnologyICC Press, 2008-05)
      High efficiency pulse tube coolers driven by linear compressors usually operate between 30 Hz and 60 Hz. This article presents the performance of a high efficiency in-line PTC with an operating frequency of 100 Hz. The ...
    • 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 ...
    • Effect of Component Geometry on Flow Non-uniformities in a Large Pulse Tube Cryocooler 

      Lewis, M. A.; Taylor, R. P.; Radebaugh, R.; Bradley, P. E. (Georgia Institute of TechnologyICC Press, 2008-05)
      A single-stage pulse tube cryocooler was designed to achieve 50 W of refrigeration power at 50 K when driven by a pressure oscillator that can produce up to 2.8 kW of acoustic power at 60 Hz. Initial experimental data ...
    • 14.5 K Hydrogen Sorption Cooler: Design and Breadboard Tests 

      ter Brake, H. J. M.; Burger, J. F.; Holland, H. J.; Meijer, R. J.; Mudaliar, A. V.; Zalewski, D. R.; Linder, M. (Georgia Institute of TechnologyICC Press, 2008-05)
      At the University of Twente, a 14.5 K hydrogen-based sorption cooler is under development. It can be used as a stand-alone 14.5 K cooler, or as a precooler, e.g., in combination with a 4 K heliumbased sorption cooler. The ...
    • Theoretical and Experimental Investigation on the Axial Temperature Mismatch and its Optimization for Coaxial Inertance Pulse Tube Cryocoolers 

      Wang, L. B.; Dang, H. Z.; Wu, Y. N.; Li, S. S.; Yang, K. X.; Xiong, C. (Georgia Institute of TechnologyICC Press, 2008-05)
      In a coaxial pulse tube cryocooler, the radial thermal conduction between the pulse tube and the regenerator has a large influence on cryocooler performance. Caused by the temperature mismatch between the pulse tube and ...
    • Analysis of Multi-Stage Joule-Thomson Microcoolers 

      Cao, H. S.; Lerou, P. P. P. M.; Mudaliar, A. V.; Holland, H. J.; Derking, J. H.; Zalewski, D. R.; ter Brake, H. J. M. (Georgia Institute of TechnologyICC Press, 2008-05)
      Microcoolers machined from glass wafers based on Joule-Thomson (J-T) expansion have been investigated for many years at the University of Twente. After successful development of singlestage J-T microcoolers with a cooling ...
    • Are P-V and T-S Diagrams Meaningful for Regenerative Cryocoolers? 

      Kittel, Peter (Georgia Institute of TechnologyICC Press, 2008-05)
      P-V and T-S diagrams are commonly used tools to illustrate thermodynamic cycles. For recuperative cycles, it is easy to idealize a cycle so that the history of a gas element can be traced on P-V and T-S diagrams as it flows ...
    • MIRI Cooler System Design Update 

      Petach, M.; Durand, D.; Michaelian, M.; Raab, J.; Tward, E. (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. ...
    • 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 ...
    • Pulse Tube Cooler with Remote Cooling 

      Raab, J.; Maddocks, J. R.; Nguyen, T.; Toma, G.; Colbert, R.; Tward, E. (Georgia Institute of TechnologyICC Press, 2008-05)
      Space pulse tube coolers are very efficient, but like all regenerative high frequency Stirling and pulse tube coolers, the cold head needs to be located near the compressor in order to minimize the input power to the cooler. ...
    • Some Insights Into Stirling Machine Behavior 

      Tucker, A. S.; Gschwendtner, M. A.; Haywood, D. (Georgia Institute of TechnologyICC Press, 2008-05)
      Almost all practical cryocoolers embody, directly or indirectly, at least some elements of the Stirling cycle in its reversed form. Through its involvement in the analysis, design and development of both Stirling engines ...
    • Secondary Pulse Tubes and Regenerators for Coupling to Room-Temperature Phase Shifters in Multistage Pulse Tube Cryocoolers 

      Radebaugh, R.; O’Gallagher, A.; Gary, J. (Georgia Institute of TechnologyICC Press, 2008-05)
      Multistage pulse tube cryocoolers require separate phase shifters for each stage. For sufficiently high frequency and acoustic power, the inertance tube is commonly used for such phase shifting. For Stirling-type, multistage ...