Relationship between GPM(Liquid) and SCFH(gases)
Relationship between GPM(Liquid) and SCFH(gases)
(OP)
A product catalog details a table of liquid flow rates GPM's and gas flow rates in SCFH's for excess flow check valves. Is a relationship available that relates GPM and SCFH for different liquified products?





RE: Relationship between GPM(Liquid) and SCFH(gases)
I assume you are not concerned with flow undergoing a phase change through the component. It would get much more involved for multiphase or flashing flow.
Regards,
SNORGY.
RE: Relationship between GPM(Liquid) and SCFH(gases)
GPM*density/molar_mass = moles/time
and then whatever conversion gets you from liters/mole/time to SCFM?
TTFN
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RE: Relationship between GPM(Liquid) and SCFH(gases)
Regards,
SNORGY.
RE: Relationship between GPM(Liquid) and SCFH(gases)
To develop a gas capacity of a check valve, you have to be working in mass flow terms or in volumes at actual conditions, not "standard" mythology. I can get a LOT more SCF's of Helium through a check valve in an hour at 1,000 psig than I can get of CO2 at 0 psig. The capacity of the valve is a function of things like fluid velocity, acceptable dP, fluid properties, etc.--none of which are available in an SCF evaluation.
David
RE: Relationship between GPM(Liquid) and SCFH(gases)
In fact the same standard volumetric error in a gasoline measurement would be 126 times more significant than the same error in a natural gas measurement, if you consider paying for BTU content in a standard volumetric unit of each. Nobody likes getting paid less than they deserve, or more than they should for these high volumes, so great care is taken in standardizing each gallon to the exact standard condition as specified in the sales contract. Liquid prover loops used at a tanker loading terminal can cost millions of dollars. When you realize that only a 1/2 % error in loading a supertanker can mean a fight over 1 million dollars, you get some idea why a proof of exact liquid quantities becomes important. At some crude import/export terminals that error could easily mean
2 Billion dollars a year (even at today's low price)
Prover Loops,
http://inf
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RE: Relationship between GPM(Liquid) and SCFH(gases)
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RE: Relationship between GPM(Liquid) and SCFH(gases)
RE: Relationship between GPM(Liquid) and SCFH(gases)
**********************
"Being GREEN isn't easy" ..Kermit
http://www.youtube.com/watch?v=hpiIWMWWVco
http://virtualpipeline.spaces.live.com/
RE: Relationship between GPM(Liquid) and SCFH(gases)
RE: Relationship between GPM(Liquid) and SCFH(gases)
**********************
"Being GREEN isn't easy" ..Kermit
http://www.youtube.com/watch?v=hpiIWMWWVco
http://virtualpipeline.spaces.live.com/
RE: Relationship between GPM(Liquid) and SCFH(gases)
Q = Fv * Cv*(ΔP/SG)^0.5
Q Flowrate through the valve gpm
ΔP Pressure Drop across the valve psi
SG Specific Gravity of the liquid related to water = 1.0
Fv Viscosity Correction
1<ν<1.5
Fv = 0.99
1.5<ν<=1000
Fv = -0.1728 * Log10ν + 1.04
ν Viscosity centiStokes
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"Being GREEN isn't easy" ..Kermit
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