KEP ES749 - Page 64

ES749 Flow Computer
60
The DP-Factor describes the relationship between the owrate and the
measured differential pressure. The owrate is computed according
to one of the three following equations, depending on the selected ow
equation:
Steam (or gas) mass ow:
Liquid volume ow:
Gas corrected volume ow:
M Mass ow
Q Volumetric ow
Q
REF
Corrected volumetric ow
K
DP
DP-Factor
ε
1
Gas expansion factor (Y
1
)
T Operating temperature
T
CAL
Calibration temperature
∆p Differential pressure
ρ Density at owing conditions
K
ME
Meter expansion coefcient x 10
–6
ρ
REF
Reference density
DP FACTOR
6.8
FLOW INPUT
(Continued)
FLOW INPUT
2 •
∆
p •
ρ
1 – K
ME
• (T – T
CAL
)
√
K
DP
ε
1
••
M =
(2 •
∆
p)
/ρ
(1 – K
ME
• (T – T
CAL
))
√
K
DP
•
Q =
2 •
∆
p •
ρ
(1 – K
ME
• (T – T
CAL
))
√
Q
REF
=
K
DP
ε
1
••
ρ
REF
•