E-888-5-E
7.4 Correction Factors in the Implementation of Temperature Correction of Petroleums
Correction factor for implementing calculation of error correction for temperature on petroleum products is
given by the formula
V.C.F = exp [
－α
T
Δ
t (.0 + 0.8
α
T
Δ
t)
α
T
= K
0
/ (
ρ
5
)
+ (K
/
ρ
5
) or
α
T
= A + B / (
ρ
5
)
where
ρ
t
: Density (t
℃
) [kg/m
]
ρ
5
: Density (5
℃
) [kg/m
]
α
T
: Thermal expansion coef
fi
cient at 5
℃
[
℃
－
]
Δ
t : Temperature difference (
Δ
t = t
－
5) [
℃
]
K
0
, K
, A and B : Constants (Shown in the table below.)
Sample kind
Density (5
℃
) range
Constants
K
0
K
A
B
CRUDE Crude oil, natural
gasoline, condensate
0.05 to .050
.
0.0
─
─
FUEL
Mobilgas
0.50
≦ρ
5
<0.05
.8
0.8
─
─
Fuel oil
0.05
≦ρ
5
<0.880
─
─
－
0.00 80.0
Kerosene,
industrial gasoline,
aviation turbine fuel oil
0.880
≦ρ
5
<0.80
5.58
0.0
─
─
Light oil, heavy oil
0.80
≦ρ
5
≦
.050
8.
0.8
LUBE Petroleum-derived
lubricants
0.8000 to .0
0.0
0.8
─
─
7.5 Flow Calculation Formula
() Total flow corrected for viscosity
Total flow corrected for viscosity is expressed as
Q
μ
f
= Q
0
×
E
×
E
where E
: Meter error correction factor dependent on viscosity and flow velocity
E
: Meter error correction factor dependent on flowmeter body's volumetric expansion (
α
)
Hence, the correction factor for correcting viscosity errors is "E
・
E
" (overall meter error).
() Total flow corrected for viscosity and temperature
Total flow corrected for viscosity and temperature is expressed as
Q
μρ
= Q
0
×
E
×
E
×
V.C.F
where E
: Meter error correction factor dependent on viscosity and flow velocity
E
: Meter error correction factor dependent on flowmeter body's volumetric expansion (
α
)
V.C.F : Volumetric conversion factor
Hence, the corrected factor for viscosity and temperature correction is "E
・
E
・
V.C.F".
