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Analyzing Transcritical CO2 Compression and Pumping Pathways

Supercritical carbon dioxide exhibits anomalous behavior in the vicinity above the critical point. The Irish physical chemist Thomas Andrews (1863) was the first who studied the supercritical behavior of carbon dioxide. He explained his observations of the fluid state above the critical point as follows: “…the surface of demarcation between the...

AVCO Sets its Sights on Mars

“You’re Going to The Moon” should now be quoted as “You’re Going to Mars.” From the 1990s downturn in the aerospace industry to today’s exponential growth, the demand for precision flow control and flow measurement has continued to follow the same growth trajectory. The focus of Alloy Valves and Control...

CCAT Observatory Approaches First Light

For the past six years, CCAT Observatory Inc., a nonprofit research organization formed by more than a dozen academic institutions led by Cornell University, has been developing a new telescope, the Fred Young Submillimeter Telescope (FYST, pronounced “feast”) and its supporting infrastructure to observe at submillimeter wavelengths. The infrastructure is...

Goddard Goings: Insight Into Its Past, Present and Future

James Webb Space Telescope-“I’m Back in the Saddle Again!” – It’s likely anyone reading this article has heard about the James Webb Space Telescope (JWST). The telescope launched on December 25, 2021 (EST) with much fanfare. Over the next month, it traveled to its observation location at the L2 Lagrange...

NASA Completes Heart of Roman Space Telescope’s Primary Instrument

The heart of NASA’s Nancy Grace Roman Space Telescope was recently delivered to Ball Aerospace in Boulder, Colo., for integration into the Wide Field Instrument (WFI). Called the Focal Plane System (FPS), it serves as the core of Roman’s camera. When the mission launches by May 2027, astronomers will use...

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Helium-3

Helium-3 (3He) is one of the two stable isotopes of helium. The other is the much more common Helium-4 (4He). Neither of these isotopes should be confused with He II, which is the second liquid phase of 4He. He II was discussed in this column in the Spring 2010 edition...

Cryopumping

Cryopumping refers to the use of cryogenic temperatures to produce vacuum in enclosed spaces. More broadly, it can also refer to the removal of gases via cryogenic temperatures from a flow stream or enclosure without necessarily resulting in vacuum pressures. This is an important application of cryogenics and is used...

Thermal Acoustic Oscillations

Thermal Acoustic Oscillations (TAO) are a common event in cryogenic systems that can have significant adverse effects on the performance of the system. TAOs are sustained pressure oscillations that can occur in tubes containing gas, closed at one end (the warm end) that have a very large temperature gradient along...

Cryogenic Treatment of Materials

F.J. Diekman Controlled Thermal Processing, Inc. info@metal-wear.com Cryogenic Processing (also called cryogenic treatment, and incorrectly “cryogenic tempering”) is a process that uses cryogenic temperatures to modify materials to enhance their performance. Cryogenic Processing involves the slow reduction in temperature of the material to at least -300°F (-185°C) and holding the...

Cryogenics in Space

Peter Kittel University of California-Berkeley pkittel@cal.berkeley.edu Space Cryogenics is the application of cryogenics to space missions. These applications fall into two broad areas, supporting space science missions and supporting the space transportation infrastructure. Science applications: The atmosphere is opaque to much of the electro-magnetic spectrum. In space, the absence of...

Cryosurgery

Review of Cryosurgery Boris Rubinsky, PhD Hebrew University School of Science and Engineering Research Center for Biomedical Engineering 78b Ross Building Givat Ram, Jerusalem 91904 Israel rubinsky@cs.huji.ac.il as published in Annual Review of Biomedical Engineering, August 2000, Vol. 2, pp. 157-187. Abstract: Cryosurgery is a surgical technique that employs freezing...

Liquefied Natural Gas

Liquefied Natural Gas as it relates to the Field of Cryogenics John W. Bonn VJ Systems, LLC johnbonn@vjsystems-lic.com Today the world is looking for a cleaner fuel and Liquefied Natural Gas (LNG) plays a large part in achieving this goal. LNG in a liquid form is at -162°C (-259°F) and...

An Issue of Pressure and Flow Rate in a Supply Tank

Please help solve this problem: A supply tank requires a vaporizer to generate sufficient pressure to pump stored fluid up into a vehicle or tank. The available head is limited as the tank level falls and it is important to minimize the system pressure drop to maintain the desired flow...

Using MLI on VJ Line Joints or Cryo Storage Tanks

When installing Multi Layer Insulation (MLI) blankets on VJ line joints or cryo storage tanks should they be wrapped and tied down tight or loose? These are usually pre-cut to size. Also should they have an access hole at the point of where the molecular sieve is installed to help...