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CSA Awards Presented at CEC/ICMC

John Weisend, CSA chairman, presented four awards at CEC/ICMC on July 1, including the first-ever William E. Gifford Award, given to a recipient in academia or at a government laboratory using a pulse tube or Gifford-McMahon cycle cryocooler as a key research component.

The 26th Space Cryogenics Workshop

This column presents a topical summary of the 2015 Space Cryogenics Workshop that was held June 24-26 in Phoenix AZ. The workshop was organized by David Plachta and Jason Hartwig of NASA/Glenn Research Center, and continued the tradition of bringing together specialists in the field of space cryogenics to discuss...

An Introduction to LNG as a Cryofuel

Technological advances in the US have unlocked massive quantities of natural gas, resulting in an abundant supply that should easily last many decades. This sustained situation has created two important consequences: the price of pipeline natural gas is low and stable, and, more significantly, the price of pipeline natural gas...

Improving the Efficiency of Helium Transfer Tubes

One must, on a daily basis, transfer liquefied gases, most notably helium from large static tanks or dewars to smaller transportable vessels. This process can become costly due to the losses sustained during transfer, which must be compensated for by reliquefying helium, requiring between 2 and 5 kW per liquid...

MiniCLEAN detector begins search for dark matter

Researchers at Pacific Northwest National Laboratory, after eight years of designing and building, have begun commissioning and cooling the MiniCLEAN detector, a small experiment with the big goal of detecting dark matter. CLEAN stands for Cryogenic Low-Energy Astrophysics with Nobles. Scientists will use the detector to search for weakly interacting...

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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...

Air Separation and Liquefaction

by Nils Tellier, PE, President, EPSIM Corporation (CSA CSM) nils@epsim.us All illustrations courtesy EPSIM Corporation Background History of Air Separation and Liquefaction This section builds on a rich history of methods to develop deep refrigeration and cryogenic liquefaction during the 19th Century. You are encouraged to read Cryo Central’s History...

Bose-Einstein Condensate

A Bose-Einstein condensate, first proposed in 1925 by Albert Einstein based on work done by Satyendra Nath Bose (the same Bose from whom the term boson is derived), is a super-cold state of matter in which almost all of the individual atoms have “condensed” down to the lowest possible quantum...

Cold Technology for Pest Control

While it does not reach temperatures cold enough to be called cryogenic, carbon dioxide snow is at the heart of a new way of dealing with unwanted pests. It utilizes a quick freezing process that takes advantage of the properties of carbon dioxide snow and has a number of benefits...

Cryogenic Finishing

The following 3 articles discuss the uses and procedures of various type of cryogenic finishing. 1) By Robin A. Rhodes, Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Cryogenic Deflashing is employed to remove undesired residual mold flash that remains on molded parts after they are removed or ejected from the...

Suppliers of regenerator materials

I was looking for suppliers of regenerator materials. Can you please provide a list of vendors for: • Lead spheres • Bronze screen discs • Rare earth materials and spheres Thank you in advance for any help you can provide.

Containing ice accumulation while recovering helium

We are implementing a system to recover helium from our Janis ST-500 continuous flow LHe cryostat. The recovery system uses standard 1/4″ plastic tubing, which we connect directly to the cryostat’s exhaust port. The problem with this setup is that the gas is still quite cold as it leaves the...