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Analyzing Transcritical CO2 Compression and Pumping Pathways

Supercritical carbon dioxide exhibits anomalous behavior in the vicinity above the critical point. The Irish physical chemist Thomas Andrews (1863) was the first who studied the supercritical behavior of carbon dioxide. He explained his observations of the fluid state above the critical point as follows: “…the surface of demarcation between the...

AVCO Sets its Sights on Mars

“You’re Going to The Moon” should now be quoted as “You’re Going to Mars.” From the 1990s downturn in the aerospace industry to today’s exponential growth, the demand for precision flow control and flow measurement has continued to follow the same growth trajectory. The focus of Alloy Valves and Control...

CCAT Observatory Approaches First Light

For the past six years, CCAT Observatory Inc., a nonprofit research organization formed by more than a dozen academic institutions led by Cornell University, has been developing a new telescope, the Fred Young Submillimeter Telescope (FYST, pronounced “feast”) and its supporting infrastructure to observe at submillimeter wavelengths. The infrastructure is...

Goddard Goings: Insight Into Its Past, Present and Future

James Webb Space Telescope-“I’m Back in the Saddle Again!” – It’s likely anyone reading this article has heard about the James Webb Space Telescope (JWST). The telescope launched on December 25, 2021 (EST) with much fanfare. Over the next month, it traveled to its observation location at the L2 Lagrange...

NASA Completes Heart of Roman Space Telescope’s Primary Instrument

The heart of NASA’s Nancy Grace Roman Space Telescope was recently delivered to Ball Aerospace in Boulder, Colo., for integration into the Wide Field Instrument (WFI). Called the Focal Plane System (FPS), it serves as the core of Roman’s camera. When the mission launches by May 2027, astronomers will use...

SpaceLogistics Sells Third Mission Extension Pod

Northrop Grumman Corporation’s SpaceLogistics has sold its third Mission Extension Pod (MEP), a propulsion “jet pack” that extends the life of legacy satellites, allowing them to operate longer and more profitably. Under a purchase agreement with Intelsat, SpaceLogistics’ Mission Robotic Vehicle (MRV), a servicing spacecraft equipped with robotic arms, will install the jet...

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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...