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Fermilab attains unprecedented quality factor for superconducting cavity

Fermilab announced November 6 that researchers had recorded a record-high quality factor while performing integrated tests on a new superconducting radio frequency cavity for the SLAC-headed Linac Coherent Light Source II project. Quality factor (Q) is a measure of a particle acceleration cavity's efficiency. A higher Q means a cavity...

MicroBooNE detects accelerator-born neutrinos

The MicroBooNE collaboration announced on November 2 that its researchers had recorded neutrinos for the first time. The sighting marks the beginning of detailed studies of these fundamental particles whose properties could be linked to dark matter, matter’s dominance over antimatter in the universe and the evolution of the entire...

Layered Thermal Insulation Systems for Below-Ambient Temperature Applications

With increasing system control and reliability requirements as well as demands for higher energy efficiencies, thermal insulation in extreme environments is a growing challenge prompting the publication of new technical consensus standards for cryogenic insulation testing and multilayer insulation (MLI) systems. Different layered thermal insulation systems such as MLI and...

Cryogenic Safety for Space Launch Vehicles During Ground Operations

United Launch Alliance launches Atlas V from Cape Canaveral and Vandenberg Air Force launch facilities, and large quantities of cryogenic propellants are stored on-site. These propellants present leak, fire and explosion hazards throughout their handling, starting from the commercial transport trailers' arrival at the launch pad and continuing through storage...

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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...