R134a compressor equation
R134a compressor equation
(OP)
I'm looking to see if there is a compressor equation other than the general isentropic ideal gas compressor equation. In particular, an isentropic equation for compressing R134A from the low pressure evaporator to the high pressure side in an HVAC system.





RE: R134a compressor equation
David
RE: R134a compressor equation
What equation and compressibility factor do you use?
Chuck
RE: R134a compressor equation
assuming centrifugal . . .
perhaps this article "Development of a Guideline for Field Testing of Gas Turbines & Centrifugal Compressors"
at this link will help you . . .
http://www.gmrc.org/docs/index.php
as far as compressibility factor, investigate the NIST website (http://webbook.nist.gov/chemistry/fluid/) for properties for r134a.
we won't do the work for you, as you are suppose to be an engineer . . . next time do not ask vague questions. be more specific!
good luck!
-pmover
RE: R134a compressor equation
I've never seen a refrig compressor that was not positive displacement. Lots of big ones are oil-flooded screw compressors. Small ones tend to be recips. Never seen a dynamic compressor in that service.
Using NIST (or their REFPROP program) for compressibility of R134A makes a lot more sense than trying to use one of the shortcut methods.
David
RE: R134a compressor equation
Thanks & Initially, i thought recip too since the refrigerant is r134a. Then I must of had a brain spasm ("internal comm error" ) when I typed the response.
-pmover