Section 6: Meter operation

 

 

Reference, Installation, and Operations Manual

June 2013

 

 

 

 

 

 

 

3-9000-743 Rev S

 

 

 

 

 

 

 

 

 

 

 

Equation 6-18 Reynolds number

 

 

 

 

 

 

 

 

Re = MAX

 

 

4

QRaw ρ(Pf

,Tf)

, 10

4

 

 

(PathFactor)

 

 

--

-------------------------------Dinμ

 

 

 

 

 

 

⎝ π

 

 

 

 

where

Re =MAX =PathFactor =

π =

QRaw =

ρ(Pf,Tf) =

Din =

μ =

Reynolds Number (dimensionless) (ReynoldsNumber)

maximum function that takes the maximum of the values within the brackets

factor to (approximately) correct for velocity profile effects

(0.94 for JuniorSonicTM meters, 1.00 for SeniorSonicTM meters) (dimensionless)

geometric constant, pi (dimensionless) (3.14159...) “raw” volumetric flow rate (m3/h) (QMeter)

natural gas mixture mass density at the flow condition (either calculated as part of internal AGA8 calculations or specified via SpecRhoMixFlow) (kg/m3) (RhoMixFlow) pipe inside diameter (m) (PipeDiam)

dynamic viscosity (Pa•s) (Viscosity)

Base-condition volumetric flow rate

The base-condition volumetric flow rate is the result converting the flow-condition volumetric flow rate to the base pressure-temperature condition. This conversion requires (1) AGA8 calculations to be either performed internally (i.e., by the meter) or externally (with the resulting compressibilities specified to the meter via the SpecZFlow and SpecZBase data points), and (2) the flow-condition temperature and pressure to be live or fixed. If AGA8 calculations are not performed (i.e., neither internally nor externally) or the flow-condition temperature and/or pressure are/is not enabled, then the base-condition volumetric flow rate is set to zero.The base-condition volumetric flow rate is calculated as shown in Equation 6-19.

200

Volumetric flow rate