GFS2102™ OPERATION AND MAINTENANCE MANUAL
© 2007 DH Instruments, a Fluke Company
Page 154
5.7.7
AVERAGE FLOW
This is a simple average of discrete flow values at the defined sample interval. Each
individual sample is summed and divided by the total number of samples summed. The
value updates for each new sample when accumulating.
n
q
q
n
∑
=
1
VARIABLE
DEFINITION
q
Average flow.
N
The number of samples in
q
Instantaneous flow
5.7.8
BEST FIT FLOW
The best fit flow is determined by calculating a real time best fit at the defined sample rate.
Unlike a standard best fit,
GFS Tools
forces the fit though zero. It is equivalent to plotting
mass on the Y axis and time on the X axis. Each individual mass update has a specific time
and thus corresponds to a discrete point on the plot. Points are added to the calculation
based on the defined sample rate of the GFS.
∑
∑
=
=
=
n
i
i
n
i
i
i
t
t
m
q
1
2
1
VARIABLE
DEFINITION
q
Best Fit flow.
i
m
Mass used at the time of sample i.
i
t
Elapsed time at the time of sample i.
Best Fit Flow