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The 18th International Cryocooler Conference

The 18th International Cryocooler Conference was held June 9-12 in Syracuse NY at the beautiful Syracuse University campus. Conference Chairman Rich Dausman and Co-chairman Dr. Chao Wang, both of Cryomech, Inc., hosted 161 attendees, including 11 students and six retirees, representing 14 different countries.

The Future with Cryogenic Fluid Dynamics

The applications of cryogenic systems have expanded over the past 50 years into many areas of our lives. This article will discuss the likely impact of cryogenic fluid dynamics on future cryogenic systems, and hopefully inspire further research to support and expand the use of existing findings and to improve...

Discovery of Helium in Natural Gas: A Retrospective

A very interesting insight into the evolution of helium production and personal insights into the life and contributions of H. P. Cady was presented by his grandson, Dr. Ralph Cady Longsworth, retired from APD Cryogenics, in a paper entitled “100th anniversary of the discovery of helium in natural gas,” presented...

Young Faces: The Next Generation in Cryogenics, Part II

In our last issue, we debuted our third installment of Young Faces, featuring young professionals who are doing interesting things in cryogenics and superconductivity and who show promise of making a difference in their fields. Here is Part II of that story, with responses listed in order of receipt.

Superfluid Helium in Space

Many scientific observations must be done in space at cryogenic temperatures a few millidegrees to a few degrees above absolute zero (-273°C). These include observations of the behavior of superfluid helium in space and observations with instruments and millimeter-wave telescopes operating at liquid helium temperatures.

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Refrigerators and Liquefiers

Two of the most common terms used in cryogenics are “refrigerator” and “liquefier.” These terms describe similar and, as will be seen, in some cases identical components. A refrigerator provides cooling (that is, absorbs heat) at cryogenic temperatures. Refrigerators typically put a working fluid (such as helium) through one of...

Air Separation

Air separation is one of the largest, as well as earliest, industrial applications of cryogenics. In this process, cryogenic temperatures are used to separate air into its constituent gases: nitrogen (78.08%), oxygen (20.95%), argon (0.93%) and carbon dioxide (0.3%). Trace gases such as krypton, neon, xenon and helium total far...

Coefficient of Performance and Figure of Merit

The coefficient of performance (COP) is used to describe the effectiveness of refrigerators, including those operating at cryogenic temperatures. The COP is defined as the amount of heat removed at the cryogenic operating temperature of the refrigerator divided by the amount of work that must be applied to remove the...

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...