Software for thermophysical properties of helium down to 1K
What are the options when it comes to software for thermophysical properties of helium at temperatures down to 1K? I know Hepak – is it still the most commonly used package?
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Refilling process of a helium cryogenic plant
I’m trying to collect some information about the refilling process of a helium cryogenic plant. Due to the physiologic losses I expect to have to foreseen a periodic refilling of helium. Our plant will be characterized by a refrigerator/liquefactor. A control cryostat with 4.5 K LHe coming from the liquefactor...
What's the best gas to use for pulse GMAW?
I have a 78″ ID vessel, 3/8″ thick shells, ½” heads, from SA-240-304L, which will have an ASME U-Stamp and I am planning on sub-arcing the seams and using pulse GMAW (ER308L for both) for the nozzles. I am comfortable with the SAW, but I am wondering about the best...
Manufacturer of liquid pump for use at 170 K
We’re in need of a liquid pump for use at 170 K in our refrigerator to pump Paratherm cryogenic heat transfer fluid. Can anyone suggest a manufacturer? Our flow rate is 16 liters/minute, and a head of 10 m. The specific gravity of the fluid is 0.85 and the viscosity...
Question about configuration of an 80 K helium circuit
I have a question about a possible configuration of an 80 K helium circuit from our cryogenic plant. A helium flow at 80 K and 18 bar is needed at the customer’s inlet. In order to decouple the refrigerator from the customer, I thought to propose the following solution: –...
Properties for steel 1.4037 at 77 K
Does anyone know the properties at 77 K for steel 1.4037 ( X 65 Cr 13) which is used for ball bearings? We are looking for values of thermal expansion.
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Adiabatic Demagnetization Refrigeration
Reaching temperatures below 1K requires different techniques than the various helium gas cycles found in large scale refrigeration plants and small cryocoolers. One of these techniques is Adiabatic Demagnetization Refrigeration (ADR). This technique takes advantage of the fact that the entropy of paramagnetic materials in a magnetic field is lower than...
Cryogen-Free
A cryogen is any fluid that operates at cryogenic temperatures (below roughly 150K – 120K). Using this definition, helium gas at 40K is a cryogen. Another more restrictive definition is to use cryogen to refer specifically to liquids at cryogenic temperatures. This is generally how it is used in the...
Cryostats and Cryocoolers
A cryostat is any device designed to maintain things (including fluids) at cryogenic temperatures. In general usage, cryostats tend to be passive devices rather than providing active cooling. In this usage, cryostats keep things cold by thermally isolating them from room temperature. This generally is accomplished by a combination of...
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...
Resistance to embrittlement at low temperatures
Could anyone advise me about resistance to embrittlement at low temperatures for the alloys in subject, i.e. does the CF10M perform like the CF8M in the same cryogenic service (-215F)? Amara Maafi Amara.Maafi@bg-group.com
Need help with temperature dependent model
I am a fourth-year student at New Zealand University. My name is Xu Ke. I have a project to generate a temperature dependent model for inductor, capacitor and diode by using PLECS. PLECS is software which acts as a toolbox for MATLAB. In my models, the temperature is very low,...
In what form is water available in LN2?
Does anybody know in what form water is available in LN2? There probably is a block of ice in the bottom of the tank. But as water comes in many shapes, I can imagine snow or crystals floating free in the LN2. When water is available in LN2, could small...
Separating gases using cryogenics
We are looking for some consulting engineers who understand how to separate gases using cryogenics. We have a new process which takes biomass and converts it to 5 gases and we need to separate these gases into their pure forms. Thanks for your help. Malcolm Draper Energy Research Group LLC...