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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Regenerators
Regenerators or regenerative heat exchangers are a key component of cryocoolers such as pulse tube cryocoolers (Cold Facts, August 2014). Regenerator performance greatly affects the coefficient of performance of cryocoolers. Improvements in regenerator design and, in particular, regenerator materials have been an important factor in the improvement of the performance...
Pulse Tube Cryocoolers
The development of pulse tube cryocoolers has been a significant topic of research and development over the past 20 or so years. Pulse tube cryocoolers have a number of advantages over other types of cryocoolers and are now available commercially. In order to understand pulse tube cryocoolers, it’s best to...
Thermal Expansion
Thermal expansion refers to the change in size (length or volume) that a material undergoes as its temperature changes. In cryogenic systems this effect can be quite large and must be allowed for in the design. In isotropic materials, which include most engineering materials, the thermal expansion is the same...
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...
Seeking technical publication that explains the science behind the cryogenic treatment of aluminum
Would you know of a technical publication that would list the benefits and explain the science behind the cryogenic treatment of aluminum, specifically a 356-T6 aluminum cylinder head casting? Eddie Phillips
Source of emissivity data for aluminum and aluminized Mylar at room temperature, 77K and 4.2K
Can anyone recommend a source of emissivity data for aluminum and aluminized Mylar at room temperature, 77K and 4.2K? Also, I would be interested in finding a facility that can measure this information. Any information will be greatly appreciated. William Einziger, GE Healthcare
Looking to purchase new LN2 freezer: any suggestions?
I will be purchasing a new liquid nitrogen freezer soon, but I am limited by space restrictions. The freezer cannot be more than 38 inches wide. However, it would be beneficial if the freezer holds a high number of racks such as 24. In addition, we prefer not to purchase...
Affordable flow meter to measure LN2 flow through a pipeline
I am trying to find out if anyone knows of or has used an affordable flow meter that can measure liquid nitrogen flow through a pipeline. It doesn’t need to be very accurate as it’s really to allow people in different departments to allocate cost rather than for scientific measurement....