Density of Saturated Vapor R-134a

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The discussion revolves around calculating the thermodynamic properties of R-134a using Octave, specifically focusing on saturated vapor properties. The user reports that their calculations for liquid density and volume, as well as saturated pressure, are accurate within 0.5% of published data. They seek guidance on how to programmatically calculate the saturated vapor properties, referencing various resources including the Dupont properties booklet and NIST data. There is a mention of using an equation of state, particularly the MBWR equation, to derive volume, which may require a guess and check method for accuracy. The conversation highlights the complexities of accurately modeling R-134a properties for effective application in refrigeration systems.
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Hi all,

Just for fun I am writing a program in Octave for calculating the thermodynamic properties of R-134a. I am using the equations in the Dupont properties booklet.
http://www2.dupont.com/Refrigerants/en_US/products/Suva/Suva134a.html

My functions for calculating the liquid density, liquid volume(of course), and the saturated pressure are less than 0.5% off of the published data.
My question is what am I missing to calculate the saturated vapor properties?

Thank You,
MON
 
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You can find the saturated properties of "regular" R134a here: http://webbook.nist.gov/chemistry/fluid/, but I'm not sure what the difference is between standard R134a and the dupont one, which seems to be made to function more effectively as a replacement in R12 systems.
 
Right, I have that link as well.
I can use the tables effectively, and I have found the properties at the conditions I needed (55/100)degF. My question is one of curiosity at this point. How to calculate it programmatically.
 
Using an equation of state such as what is published in this paper - http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=JPCRBU000023000005000657000001&idtype=cvips&prog=normal
 
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Bump.
 
What, our answers weren't good enough? Don't just bump the thread, elaborate what it is you're still looking for
 
I guess I must have a subscription at work for the link I provided earlier, but a quick google search reveals that http://www.nist.gov/srd/PDFfiles/jpcrd480.pdf. Again, that is the equation of state for R134a that several computer programs use for property data.
 
Sorry about the delay. My question with the MBWR equation of state was determining the Volume from inside the summation. I can't directly solve for it, so I am assuming I need to put it into a guess and check routine until the error falls into an acceptable range?
 
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