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Liquid Air Phase Chart

Liquid Air Phase Chart

Liquid Air Phase Chart

I'm looking for a phase chart that shows temp as a function of pressure, for an 80%N2/20%O2 mixture of liquid air.

RE: Liquid Air Phase Chart

For $200 you can purchase a database from  National Institute of Standards and Technology that includes air and may other components.  Take a look at http://www.nist.gov/srd/nist23.htm.

If you can be more specific about the temperature, pressure, and quality ranges you're looking at, I could probably get you some data.


RE: Liquid Air Phase Chart

Tango, this would be for a liquid air mix of O2 20%, N2 80%, with a pressure range, 5 to 25 psig. For instance, at a saturation press of 5 psi, what would be the temp? What would be the respective temperatures for pressure saturations of 5, 10, 15, 20, and 25 psig respectively?  

RE: Liquid Air Phase Chart

For Liquid Air (N2 0.7812, O2 0.2096, Ar 0.0092 mol%), you'd have:
Vapor Phase    Vapor Phase
Pressure    Temperature
(psia)            (°F)
5.0000            -332.72
10.000            -323.45
15.000            -317.32
20.000            -312.60
25.000            -308.69
30.000            -305.34
35.000            -302.38
40.000            -299.72
55.000            -292.99

Depending on the accuracy you want, your 80/20 mol% mixture is:
Vapor Phase    Vapor Phase
Pressure    Temperature
(psia)            (°F)
5.0000            -332.92
10.000            -323.68
15.000            -317.56
20.000            -312.85
25.000            -308.96
30.000            -305.62
35.000            -302.67
40.000            -300.01
45.000            -297.59
50.000            -295.37
55.000            -293.30


RE: Liquid Air Phase Chart

Perfect! Would you mind doing the same calculations for LN2?

RE: Liquid Air Phase Chart

LN2 Saturation:
Pressure    Temperature
(psia)    (°F)
5.0000    -335.02
10.000    -326.05
15.000    -320.12
20.000    -315.55
25.000    -311.78
30.000    -308.53
35.000    -305.67
40.000    -303.10
45.000    -300.76
50.000    -298.60
55.000    -296.60

Reference is "NIST Standard Reference Database 23, Version 7.0".  


RE: Liquid Air Phase Chart

Thanks again!

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