He II: From the Lab to an Engineering Fluid
Dr. John Weisend II traces the evolution of He II as a cryogenic coolant, discussing both its applications and the research and development activities required to apply He II to large-scale systems.
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History of the CSA Website
In 1991, the World Wide Web came into being at CERN, with other scientific laboratories around the world following close behind. In early 1995, Joel Fuerst undertook the development of a website for CSA.
A Half Century of Cryogenics and CSA
"1964 seems just like yesterday to me, yet it was 50 years ago. The Cryogenic Society of America was born that year, and I was just beginning my professional career in cryogenics." Dr. Ray Radebaugh reviews some of the industry's and CSA's major advances from 1964 to the present.
CSA Awards and Recognitions over the Years
CSA's first award was named for Robert W. Vance, who was one of the guiding lights who was present at the founding and kept the society going through some rough times.
Cryocoolers to Monitor Global Surface Temperatures from Space
The Cryocooler Development and Engineering Group at Airbus Defence and Space, formerly known as Astrium, has delivered the first of two space cryocooler systems, scheduled to launch in mid-2015 on the European Space Agency’s twin Sentinel 3 satellites.
The Rebirth of CSA
In 1984, 20 years after its founding, the Cryogenic Society of America was re-incorporated in the state of Illinois under new leadership. President Romuald (Ray) Szara explained the changes in a letter to the membership quoted in Vol. 1, No. 1 of the new CSA magazine, Cold Facts.
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Two-Phase Flows
Two-phase flows are those flows in which there is a mixture of two physical states (solid, liquid or vapor). In cryogenic applications, such flows are almost always a mixture of a cryogenic liquid along with its corresponding vapor. A mixture of liquid helium and helium vapor would be a typical...
Supercritical Fluids
A supercritical fluid is defined as a substance whose temperature and pressure exceed those of its critical point. Every pure substance has a critical point that is defined in thermodynamic space by a critical temperature and a corresponding critical pressure. For example, the critical point for helium has a critical...
Brayton Cycle
The Brayton cycle is one of the many thermodynamic cycles used to generate cooling at cryogenic temperatures. Strictly speaking, when referring to cooling we should call this the reverse Brayton cycle as the original Brayton cycle describes the process of power generation or propulsion via a gas turbine. In many...
Primary Standards
Elie K. Track Hypres, Inc. elie@hypres.com http://www.hypres.com/ Primary standards involve the exact definition and realization of units of measurement for various quantities, time, length, mass, voltage, resistance, current, etc. International agreements based on the latest scientific knowledge define those units, and their realizations vary depending on the unit itself. For...
Shrink Fitting
Robin A. Rhodes Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Shrink fitting, (or “compression fitting” as it is sometimes called), is a method used to insert a pin or bushing into a housing or other assembly requiring an extremely tight tolerance fit. It can be used as an alternative to...
Telecommunications
From the Winter 2004 issue of Cold Facts magazine The recent M-Calc IV — 4th Industry Assessment workshop discussing military and commercial applications for low-cost cryocoolers, held in November in San Diego, highlighted progress being made in cryogenics as applied in telecommunications. The reliability and long lifetime of projects now...
Wind Tunnels
Dr. Robert Kilgore The development of the cryogenic wind tunnel is one of many significant breakthroughs in both cryogenics and wind-tunnel technology made during the past millennium. Interest in the development of high-speed commercial and military aircraft resulted in a review of problems of flow simulation in transonic wind tunnels...
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...
Separated layers of ice over a pipe
I want to know that why there are different layers of ice over a pipe carrying a cryogenic fluid, each layer separated with clear marks / lines? What do these layers signify?