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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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Cold Compressors

A common way to provide cooling below the normal boiling point of helium (4.2K) is to reduce the pressure above the bath of liquid helium, thus also reducing the bath’s equilibrium saturation temperature. For example, to produce a 1.8K bath of liquid helium, the saturation pressure has to be reduced...

Kapitza Conductance

Kapitza conductance refers to the heat transfer between a solid surface and a fluid that covers that surface. Fundamentally, it describes the inherent difficulty in transferring energy from a solid to the fluid covering the solid surface. This phenomenon was first observed by P. L. Kapitza in 1941 while studying...

Thermosyphons

A thermosyphon (or thermosiphon) is a device that transfers heat via natural convection in a fluid. The natural convection is driven by gravity with the colder, denser fluid flowing downhill and the warmer, less dense fluid flowing back up. Thus, thermosyphons connect an object to be cooled with a reservoir...

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...