Cryocoolers, a Brief Overview
Cryocoolers are a type of refrigerator designed to reach cryogenic temperatures. Engineers use the term most often for smaller systems, typically no larger than table-top size, with input powers less than about 20 kW.
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2nd International Conference on Cryogenics and Refrigeration Technologies
The city of Bucharest hosted the 2nd International Congress on Cryogenics and Refrigeration Technologies May 7-10, welcoming attendees with delicious food, pleasant parks, numerous museums and plenty of research and conversation.
Columbia Researchers Squeeze Light into Nanoscale Devices and Circuits
Columbia investigators have invented of a novel "home-built" cryogenic near-field optical microscope that has enabled them to directly image, for the first time, the propagation and dynamics of graphene plasmons at variable temperatures down to -250°C.
OPERA Presents Its Final Results on Neutrino Oscillations
In a paper published in the journal Physical Review Letters, the OPERA collaboration reports the observation of a total of 10 muon to tau-neutrino conversion events, demonstrating unambiguously that muon neutrinos oscillate into tau neutrinos on their way from CERN, where muon neutrinos were produced, to OPERA at the Gran...
NASA’s Cold Atom Lab Launches, Coldest Spot in Universe Now on ISS
NASA's Cold Atom Lab (CAL) facility was included in the cargo that launched to the International Space Station on the Orbital ATK CRS-9 mission. CAL produces clouds of atoms that are ten billion times colder than deep space, using lasers and magnetic forces to freeze the atoms until they are...
Canadian Researchers Working on Novel MRI for ISS
The Canadian Space Agency has awarded a research team at the University of Saskatchewan a contract to design and engineer an ankle-sized MRI device for the International Space Station. The device, according to the team, will ultimately monitor the bone health of astronauts during prolonged space trips, where weightless conditions...
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Dewar
A dewar is a type of cryostat named after Sir James Dewar, the researcher who first developed the concept of a vacuum insulated container with silvered walls to reflect thermal radiation. Dewar was the first to liquefy hydrogen, and he created the device to store his discovery. The thermos bottle...
Stirling and Gifford-McMahon Cryocoolers
Stirling and Gifford-McMahon (GM) cryocoolers are two of the most commonly used cryocoolers in cryogenics. Both devices have a significant industrial base and operate at a wide range of temperatures and capacities. The thermodynamic cycles for both of these cryocoolers are quite similar. The Stirling cycle consists of a compressor,...
Liquefied Natural Gas (LNG)
A significant commercial application of cryogenics is the liquefaction, transport and storage of natural gas. Liquefied Natural Gas (LNG) is generally 95 percent methane with a few percent ethane and much lower concentrations of propane and butane. LNG liquefies at 111.6 K. Unlike many applications of cryogenics, the motivation for...
Cryogenic Electronics
Randall Kirschman, consulting physicist, Mountain View, California ExtElect@gmail.com Cryogenic electronics—the operation of electronic devices, circuits, and systems at cryogenic temperatures—has been a valuable technology for decades. Cryogenic electronics (also referred to as low-temperature electronics, or cold electronics) can be based on semiconductive devices, on superconductive devices, or on a combination...
Particle Physics: High Energy Physics
Cryogenics and High-Energy Physics 1. From symmetry magazine: http://www.symmetrymagazine.org/cms/?pid=1000627: Cryogenics is the study of how materials behave at temperatures near absolute zero. In high-energy particle accelerators, such frigid temperatures reduce the electrical resistance of wires in superconducting magnets, increasing the magnet strength and allowing faster particle acceleration. The same holds...
HTS Degaussing Systems
From the Spring 2009 issue of Cold Facts (Volume 25, Number 2): Thanks to a joint project by the US Navy and a number of industry partners, high temperature superconducting (HTS) technology is now at the heart of an advanced degaussing system aboard the USS Higgins at the naval station...
Magnetic Resonance Imaging
From http://www.superconductors.org: An area where superconductors can perform a life-saving function is in the field of biomagnetism. Doctors need a non-invasive means of determining what’s going on inside the human body. By impinging a strong superconductor-derived magnetic field into the body, hydrogen atoms that exist in the body’s water and...
Information on how the emissivity of the panel changes with air fouling?
I work at a facility with a large thermal vacuum chamber. We are using both nitrogen and helium shrouds.
In search of a calculation for designing a cryostat
I am a final year physics student at the University of Birmingham, and as part of a group I am currently designing a cryostat. One of the calculations I need to make (very soon!) is how much heat will be conducted down the walls. All information I have found so...
Safety of ethylene glycol and pressurized oxygen
We are reviewing the product design of liquid filled differential level gauges and want to insure that they meet the industry requirements. The former license owner had authorized that a fill fluid of ethylene glycol (68%) and distilled water (32%) could be used for oxygen service up to 500 psi....
Heat flux in case of vacuum loss on cryogenic surfaces?
Is there anyone who has information about the heat flux in case of vacuum loss on cryogenic surfaces?