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Problem sending LN2 through hoses – need to minimize heat leak

We use liquid nitrogen at our power station to freeze light and heavy water in piping. The ice plug formed within the piping acts as a “valve” and allows us to work on a section of the piping system that otherwise cannot be isolated. The liquid nitrogen enters a jacket...

Cyclotron founder Henry Blosser leaves large legacy at MSU

When Michigan State University went looking for someone who could build a cyclotron from scratch, Henry Blosser wasn’t the first choice. He got the job only after two of his co-workers at Oak Ridge National Laboratory and a Canadian researcher had turned it down.

GE completes trials of HTS technology for power generation

GE’s Power Conversion has successfully completed trials of Hydrogenie, a power generator incorporating groundbreaking technologies that enable highly efficient production of electricity in a small space. Hydrogenie makes use of superconductors instead of copper for the rotor windings on the motor, operating at 43 Kelvin or -230°C.

Light tsunami in a superconductor

An international research team at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has managed to selectively influence superconductivity with a powerful terahertz laser. This very precise laser light turns into a vortex which moves through the superconductor like a tsunami.

AMS experiment measures antimatter excess in space

The international team running the Alpha Magnetic Spectrometer (AMS) announced on April 3 the first results in its search for dark matter. The AMS paper, to be published in the journal Physical Review Letters, reports the observation of an excess of positrons in the cosmic ray flux. AMS spokesperson Professor...

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Joule-Thomson Effect

The Joule-Thomson (JT) effect is a thermodynamic process that occurs when a fluid expands from high pressure to low pressure at constant enthalpy (an isenthalpic process). Such a process can be approximated in the real world by expanding a fluid from high pressure to low pressure across a valve. Under...

Current Leads

One of the challenges of using superconducting magnets is the connection of the magnet to a room temperature power supply. This is accomplished via current leads. The trick is that current leads should ideally have a low heat leak, since they connect room temperature to cryogenic temperature, while at the...

Multilayer Insulation

Multilayer insulation (also referred to as superinsulation) is a key component in the reduction of heat leak to cryogenic systems due to thermal radiation. MLI consists of a series of uncooled reflective surfaces placed in the vacuum space between two surfaces, one warmer than the other. Generally speaking, for ideal...

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...