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AGA11
AGA 11 is a publication by the American Gas Association, titled
"Measurement of Natural Gas by Coriolis Meter."
A Coriolis meter measures mass directly, without having to infer mass through the measurement of actual volume. For more information on how this type of meter works, go
here.
There are not very many equations or complicated algorithms in AGA 11. It is mainly a guide on the proper deployment of Coriolis meters for the measurement of natural gas flow. However, it does contain one very simple calculation which is the only one required to convert mass to equivalent volume: the gas density. This is the equation performed on this page.
The density equation calculates real gas density at specified conditions. It requires a pressure, temperature, gas mole weight and compressibility. Compressibility is calculated by your favourite equation of state, such as
AGA 8.
The algorithm for the calculation is extremely straightforward. It is really just the application of the real gas law to a specific set of conditions.
Real gas law: P * V = n * R * T * Z
The mass is the
molar weight
per mole: M = n * MW
Density is mass per unit volume: Rho = M / V
Therefore:
Rho = P * MW / ( R * T * Z)
AGA11: Enter a temperature, pressure, mole weight and compressibility.
Temp (Deg C) =
Pressure (kPaA) =
Compressibility (at above P, T) =
Mole weight (kg/kmol) =
Results Table