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A Cryogenic Valve Primer

It is remarkable but true that we’ve used valves to control the flow of liquids for thousands of years. The city of Pompeii’s water system, for example, utilized quarter-turn style valves that were in principle very similar to those in use today. Cryogenic valves, while unique, are similar to these...

Air Liquide Designing Cryogenic System for ITER

Air Liquide has substantial expertise in designing, fabricating and installing large capacity gas liquefaction and refrigeration systems. Its engineers have completed major cryogenic installations, for example, at CERN and KSTAR (the South Korean Tokamak) and are now working on ITER, providing the project with a centralized helium cryogenic plant and...

Forget Nitro Brew Coffee, Meet Nitro Bean

The perfect roast for your next cup of joe might just come from liquid nitrogen chilled coffee beans. A team from the University of Bath, working with the Bath coffee shop Colonna & Smalls, reports that chilling roasted beans before grinding results in small uniform coffee grinds. This provides for...

NASA’s MIRI Cryocooler Passes Inspection, Set for Installation on Webb Telescope

Scientists at NASA's Jet Propulsion Laboratory (JPL) have completed testing of a first-of-its-kind cryocooler for NASA's James Webb Space Telescope. The cooler will chill one of the telescope's four instruments, the Mid-Infrared Instrument (MIRI), a device key to catching faint whispers of light from the very first stars born in...

LIGO Detects Gravitational Waves for a Second Time

Scientists from the LIGO Scientific Collaboration have observed gravitational waves for a second time, according to an announcement made on June 15 during the 228th meeting of the American Astronomical Society in San Diego. The detection of the waves—ripples in the fabric of spacetime—was made on Dec. 25 by both...

EMIR Spectrograph Installed on Gran Telescopio CANARIAS

Engineers at the Roque de los Muchachos Observatory have attached the EMIR spectrograph to the Gran Telescopio CANARIAS (GTC), realizing a more than decade long design and fabrication process. The cryogenic instrument was designed, built, assembled and verified entirely at the IAC (Astrophysics Institute of Canrias). It will produce images...

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Mixed Refrigerant Cycles

Most cryogenic refrigeration systems, both large scale systems and cryocoolers, use helium as a working fluid. There are a number of advantages to helium, not the least of which is that helium remains a fluid down to the lowest achievable temperatures. In order to freeze helium, pressures of over 20...

Fountain Pumps and He II Phase Separators

Helium II (He II), the second liquid phase of the 4He isotope described in this column in Cold Facts Spring 2010 (http://2csa.us/he2), can be modeled as consisting of two interpenetrating fluids. One, the superfluid component, has zero viscosity and entropy and the other, the normal fluid component, has nonzero viscosity...

Turboexpanders

A vital technology in the refrigerators and liquefiers described in Cold Facts Volume 31 Number 3 is that of turboexpanders. These devices are rotating machines in which the process fluid (e.g., helium) does work against the turboexpander while moving from high pressure to a lower pressure and thus is cooled....

Cryogenic Electronics

Randall Kirschman, consulting physicist, Mountain View, California ExtElect@gmail.com Cryogenic electronics—the operation of electronic devices, circuits, and systems at cryogenic temperatures—has been a valuable technology for decades. Cryogenic electronics (also referred to as low-temperature electronics, or cold electronics) can be based on semiconductive devices, on superconductive devices, or on a combination...

Particle Physics: High Energy Physics

Cryogenics and High-Energy Physics 1. From symmetry magazine: http://www.symmetrymagazine.org/cms/?pid=1000627: Cryogenics is the study of how materials behave at temperatures near absolute zero. In high-energy particle accelerators, such frigid temperatures reduce the electrical resistance of wires in superconducting magnets, increasing the magnet strength and allowing faster particle acceleration. The same holds...

HTS Degaussing Systems

From the Spring 2009 issue of Cold Facts (Volume 25, Number 2): Thanks to a joint project by the US Navy and a number of industry partners, high temperature superconducting (HTS) technology is now at the heart of an advanced degaussing system aboard the USS Higgins at the naval station...

Magnetic Resonance Imaging

From http://www.superconductors.org: An area where superconductors can perform a life-saving function is in the field of biomagnetism. Doctors need a non-invasive means of determining what’s going on inside the human body. By impinging a strong superconductor-derived magnetic field into the body, hydrogen atoms that exist in the body’s water 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...