Section 6: Meter operation

Reference, Installation, and Operations Manual

June 2013

3-9000-743 Rev S

 

 

For all other port angles,PortAngleFactor = 1

where

Vchord

Cchord

Lchord

Xchord

t1

t2

=chord average gas velocity (m/s) (FlowVelA ... FlowVelD)=chord average sound velocity (m/s) (SndVelA ... SndVelD)=chord “L” dimension (m) (LA ... LD)=chord “X” dimension (m) (XA ... XD)

=chord average transit time in the upstream direction (s) (MeanTmA1 ... MeanTmD1)

=chord average transit time in the downstream direction (s) (MeanTmA2 ... MeanTmD2)

Note that a positive chord gas velocity indicates flow in the forward direction whereas a negative chord gas velocity indicates flow in the reverse direction.

6.1.6Average weighted sound velocity

The average weighted sound velocity is calculated as the average of the active chord sound velocity measurements as shown in the equation below:

Equation 6-3 Average weighted sound velocity

 

 

 

Wtchord Cchord

CAvg

=

ActiveChords

 

------------------------------------------------------------------NumActiveChords

 

 

 

where

 

 

 

 

CAvg

=

average weighted sound velocity (m/s) (AvgSndVel)

Wtchord

=

chord weight (dimensionless) (WtA ... WtD)

Cchord

=

chord average sound velocity (m/s)

 

=

(SndVelA ... SndVelD)
NumActiveChordsnumber of active chords

188

Average weighted sound velocity