Contrec 515 Series with GN13 application measures the volume, mass and gross heat content of natural gas. The instrument uses single or stacked differential pressure mass flow inputs and analogue temperature and pressure sensor inputs.
The instrument calculates the flow according to generic differential pressure equations and incorporates the conditions at which the flowmeter was calibrated.
The AGA-8 Detail Characterization Method is used to obtain accurate values of density and compressibility factors for the flow calculations.
CALCULATIONS
The gas density and compressibility factor calculations are based on the SGERG (AGA-8 Gross) equations. The calculations are valid for the region:
-8.0°C < t < 62.0°C P < 12MPa
17°F < t < 143.0°F P < 1740psia
FORMULAS
Mflow = volume flow• ρflow
corrected flow = Mflow/ρ ref
Heat flow = Mflow•Hm
Where:
Mflow = mass flow
ρflow = density at flow conditions
ρ ref = density at reference conditions
Hm = mass gross heating value
