1_designing ultrasonic flow meters
TRANSCRIPT
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Technical considerations in
designing ul trasonic flow
meters.
Jan G. Drenthen
Marcel Vermeulen &
Hilko den Hollander
KROHNE Oil & Gas
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ALTOSONIC V12
6 paths with a single reflection in each path
No flow conditioner required
Integrated swirl compensation
ALTOSONIC V12-D
6 paths with direct mode
Flow conditioner required
For low pressure and high CO2
reflective and non-reflective designs.
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3
Principle USM
cdVCOS
t
1-
t
1
2
l=v
baab
m
cos
DiL
Trd B
Trd A
send
receive
cos
vc
l=t
U
ba
cosv+c
l=t
D
ab
receive
send
Cu
v
baab t
1
t
1.
2
LC
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4
Principe USM
t
1
-t
1
2
l
=vbaabcos
For US meters the velocity is only a function of the time
and the geometry of the meter body.
Therefore:
The measurement is independent from the fluid
properties.
The meter calibration is valid for use at all pressures. The meter curve is linear
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5
Where do the fluid properties and pressure come into
play?
In the correction curve ifa Reynolds type correction is
used.
VD
..Re
Pressure:
In a correction factor of the meter, as described inChapter 4.7 (a unique feature of the 17089 !)
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6
Reynolds dependent Flow profi le
Re < 10.000 Re = 1000.000
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Reynolds correction as function of the path posit ion
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Single path meter
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Test result of a single path meter.
Lucky Shot 1:
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NRLM certificate
Lucky Shot 2:
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Flow profi le distortion
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12
Lowest Uncertainty
Highest Reliability
What are the essential requirements for Custody Transfer meters?
Measurement accuracy (Typical technical data sheet)
Uncertainty
0.5% of measured value, uncalibrated
0.2% of measured value, high-pressure flow calibrated(relative to calibration laboratories)
0.1% of measured value, calibrated and linearized
Repeatability 0.1%
What you see is the top of the iceberg
Dont let datasheets mislead you!
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The Ice berg specifications
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Uncertainty
Non-linearity,
Repeatability
Due to Installation effects
Due to possible contamination
Iceberg specification
ISO 17089 + OIMLR 137
AGA 9
Expert systems
Calibration
Commissioning
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15
ISO 17089
OIML R137
The transferability of the calibration curve to the field.
-0,50%
-0,40%
-0,30%
-0,20%
-0,10%
0,00%
0,10%
0,20%
0,30%
0,40%
0,50%
0 500 1000 1500 2000 2500 3000
(Initial) Base 15 bar
Base15 bar FC
Base10 bar
Diameterstep +3%
Diameterstep -3%
Elbow 10D0deg
Elbow 10D90deg
OOP 10D 0deg
OOP 10D 90deg
OOP Exp.10D0deg
Base15 bar
REVERSE
Renewedbase 15bar2008-10-14
Elbow 10D0deg
Renewedbase 15barrepeat 2008-10-22-2,00%
-1,50%
-1,00%
-0,50%
0,00%
0,50%
1,00%
1,50%
2,00%
0% 20% 40% 60% 80% 100%
Uncertainty
2%
-2% -0,5%
0,5%
?
Ideal conditions Real conditions
ISO 17089 A meter calibration curve without the guarantee that the meterbehaves the same way in the field as at the calibration facility is meaningless
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-0.8 %
-0.6 %
-0.4 %
-0.2 %
0.0 %
0.2 %
0.4 %
0.6 %
0.8 %
0 1000 2000 3000 4000 5000
Diff
erence
Diff. %
U (K=1)U (K=2)
U (K=3)U (K=4)
How does contamination over time affects the meter performance?
Performance
Monitoring
-2,00%
-1,50%
-1,00%
-0,50%
0,00%
0,50%
1,00%
1,50%
2,00%
0% 20% 40% 60% 80% 100%
Uncertainty
Ideal conditions Real conditions
?
The quality of measurement over time.
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Fundamentally, after the calibration 2 vital questions remain:
How can we guarantee that the meter behaves the same way in the field
as in the calibration facility?
How can one be assured that the meter performance is not deteriorated
by fouling?
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Why highest possible accuracy?
Because we measure billions of
and accountants appreciate lowest uncertainty.
$
Accuracy
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The Netherlands: Production CT metering: 8x 24
Examples of metering stations
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Examples of metering stations
Left:
GERMANY: gas import1x 30, 2x 20, 2x 16
Right:OMAN: LNG feed4x 16
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Money involved at large metering stations
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The minimum you could lose
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Pay back time
23
At 0.1%, the payback time of the meters is within a few number of weeks.
So the decision on the measurement should be made on the performance
rather than on the lowest price.
Dutch saying:
The bitter taste of a poor performance lasts longer than the sweet taste of a
cheap buy.
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Accuracy depends on:
Acoustic path configuration
The number of paths
The calculation schedule of individual paths
Major issues are:
Profile distortion
Swirl
Multi-path Flow Meter Configuration
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Meter design
1. Using mathematics dating from the 1830s (such as used in the Westinghouse patent from 1968 and stillapplied in many parallel paths meters).
And / or..
25
Gauss J acobi Legendre Chebyshev
In selecting the acoustic path configuration there are 2 possibilities:
2. by applying flow research and using physical models such as CFD. Only then thetechnology can progress.
CFD goal: the creation of a flow profile database
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Flow calculation models
CFD:
Results depend on:
the boundary conditions
the calculation grid
Results always look nice, but
experiments are always necessary.
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Flow calculation models
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Flow profi le distortions
Reducer tests at the University of Erlangen
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Laboratory tests
Reducer tests at the University of Erlangen
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Laser Doppler and CFD calculation
30
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 10
0.5
1
1.5
r/R [-]
v/vgem[-]
Position x: 0R
Disturbed profile 5.5 D after a single 45 bending
measured in a 135 plane
Measured LDA
Theory (30% and 0.6R)
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Analyt ical model
Theoretical models:
- Undisturbed fully developed pipe flow t heory- Mathematical hydrodynamic disturbance
functions
- Wall roughness theory
- Cavity correction theory
- Flow integration scheme
Input:
- Experimental LDA/PIV Data
- Geometrical parameters
- Hydrodynamic parameters
(e.g. Reynolds number)
Computation:
Path positi on optimization
Final design-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
0
0.5
1
1.5
r/R [-]
v/vgem[
-]
Position x: 0R
Disturbed profile 5.5 D after a single 45 bending
measured in a 135 plane
Measured LDA
Theory (30% and 0.6R)
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Analytical model
Example of path sensitivity calculation for a 4 path meter for
30+ different pipe configurations
Offset mean error axial disturbances relative to a fully developed pipe flow
-0.5
0.5
1.5
2.5
3.5
4.5
0.1 0.2 0.3 0.4 0.5 0.6 0.7
Position Path xR [-]
Offseterror[%]
IV beam
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Analytical model
Offset mean error axial disturbances relative to a fully developed pipe flow
-0.5
0.5
1.5
2.5
3.5
4.5
0.1 0.2 0.3 0.4 0.5 0.6 0.7
Position Path xR [-]
Offseterror[%]
V beam
Example of path sensitivity calculation for a 5 path meter for
30+ different pipe configurations
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Example of 4 possible configurations
4 Beam 12 Chordsversion 1
12 Chordsversion 2
Laminar flowTurbulent flow
Multipath configurations
Triangelmodel
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Profile distortion
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Distortions in compliance with
10D
10D
5D
5D
SB Re/Ex DBooP
ISO17089
80D
80D
0D
0D
OIML R137
DBooP/Ex DBooP/Ex/HMP
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Schematic layout
Testing in Lintorf
Total uncertainty: 0,3%
Repeatability: 0,1%
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Testing in Lintorf
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Straight path and reflective path tests
V12_d
V12
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Straight path: ideal flow profile
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Straight path: Flow profile after a single bend
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Straight path Crossed or reflective path
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Straight path: Flow profile Double out-of-plane bend
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0,0%
0,1%
0,2%
0,3%
0,4%
0,5%
0,6%
0,7%
0,8%
0,9%
3 criss-crossed
chords
4 criss-crossed
chords
3 parallelchords
5 criss-crossed
chords
4/5 parallelchords
5-pathtriangle
8 chordscrossed in-
plane
12-Vchords
crossed in-
plane
Path Configuration
EstimatedUncertainty(%)
V12 meter
Flow Profile Effects (no swirl)Gregor Brown: NEL conference 2006, KL.
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Swirl +
-0
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Chord configurations
Paths in the
same direction
Criss-
crossed
Triangle
model
V 12
technology
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Swirl comes in 2variations
After a
singlebend
After a
double out-of-plane
bend
The swirl velocity vector at the bottom changes in direction !
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Flow profile distortion and swirl
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Swirl elimination in each of the individual measurement planes
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Swirl elimination
Reflective or crossed -technology
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Difference between in-plane and out-of-plane designs
In-plane designs have 2 chords in the same
horizontal plane to completely eliminate the
swirl.
Out-of-plane designs have the cords which
are supposedly aimed to compensate for the
swirl at the different positions in the vertical
plane.
The paths do not cross in the same horizontal
plane.
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Difference between in-plane and out-of-plane designs
In-plane designs have 2 chords in the same
horizontal plane to completely eliminate the
swirl.
Out-of-plane designs have the cords which
are supposedly aimed to compensate for the
swirl at the different positions in the vertical
plane.
The paths do not cross in the same horizontal
plane.
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Out-of-plane chord designs
Out-of-plane chord designs try to compensate for the swirl by combining
cords at the same radius position.
Bottom pathchanges in direction
Paths in same direction Paths in criss-crossarrangement.
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2 parallel chords in detail, paths in same direction
-
+
-
-
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Ideal swirl profile Real swirl profile
Swirl compensation with out-of-plane paths(paths in same direction)
++
--
++
-
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2 parallel chords in detail, in a criss-cross arrangement
+
+
+
-
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Ideal swirl profile Real swirl profile
Swirl compensation with out-of-plane paths(paths criss-crossed)
++
++
+++
+
Th diff b t i l d i d th f i ti
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The difference between in plane and criss-crossed path conf igurations
Each of them is optimized for either:
. a single bend configuration
. or for a double out-of-plane bend
. But neither of them can handle both !
. Both are unsuitable for non symmetrical
swirl
The only way to overcome these problems is by eliminating the swirl in
each of the individual the measurement planes
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The impact of Swirl on the measurement result in practice
High level swirl test
Low level swirl in an official AGA9 Meter run
Bill Frasier, Ceesi
Ceesi Colorado Springs Ultrasonic Workshop 2011
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Benchmark ultrasonic gas f low meters 20 /DN500
Archive photo: GL Flow Centre Bishop Auckland
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Participants
61
UFM i d i th G t t
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Out-of-plane
swirl compensation
UFMs in compared in the Gazprom test.
In-plane swirl elimination
Latest model
Z k fl diti t f 28D t i ht i
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Zanker flow conditioner upstream of a 28D straight pipe
PTB plate, swirl angle 45
Zanker flow profiler Fully developed flow (ideal conditions)
Disturbed flow with swirl (mimicking Header + Tees)
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Real world conditions: Header with 2 Tees
Courtesy: 64CFD: Computational Fluid Dynamics
T t t Bi h A kl d
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Test set-up Bishop Auckland 20 (DN500) / ANSI600 / natural gas @ 40 bar
13D = 6.5m28D = 13.9mMeter 1 Meter 2
Meters 1 & 2
ideal conditions
ideal conditions
swirl
Meters 3, 4 & 5ideal conditions
swirl
Real world conditions with swirl:
Ideal conditions:
Meters 3, 4 & 5
Meters 1 & 2
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-1
-0,8
-0,6
-0,4
-0,2
0
0,2
0,4
0,6
0,8
1
0 2000 4000 6000 8000 10000 12000
m3/h
%
erro
r
0,36%
0,61%
Test 1
Test 2
M1
M1 M2
M2
Test 2, meter2Test 1, meter2
Test 1, meter1
Test 2, meter1
Ideal conditions: Meters 1 & 2
Meter 1 showed irregular behavior even under ideal conditions
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-1
-0,8
-0,6
-0,4
-0,2
0
0,2
0,4
0,6
0,8
1
0 2000 4000 6000 8000 10000 12000
m3/h
%
error
0,36%
0,61%
-1
-0,8
-0,6
-0,4
-0,2
0
0,2
0,4
0,6
0,8
1
0 2000 4000 6000 8000 10000 12000
m3/h
%
erro
r
0,36%
0,61%
Test 1
Test 2 R SM1 M2
M1 M2
M1, Test 2 repeatafternoon
M1, Test 1 morning
M1, Test 1 repeatafternoon
M1, Test 2 morning
Meter 1 showed irregular behavior even under ideal conditions
Meter M1 suffered from irregular baseline behavior and was
therefore disqualified
Ideal condit ions: all manufacturers (scale 1%)
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-1,00
-0,80
-0,60
-0,40
-0,20
0,00
0,20
0,40
0,60
0,80
1,00
0 2000 4000 6000 8000 10000 12000%
m3/h
Ideal condit ions: all manufacturers (scale 1%)
Test 2 M1 M2
Test 5 M3 M4 M5
M3M2
M4
M1
M5
rejected on irregular baseline behavior
Real world conditions; flow with swirl (scale + 7 5 to 20%)
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-20,00
-17,50
-15,00
-12,50
-10,00
-7,50
-5,00
-2,50
0,00
2,50
5,00
7,50
0 2000 4000 6000 8000 10000 12000
%
m3/h
rejected on irregular baseline behavior
69
Real world conditions; flow with swirl (scale + 7.5 to - 20%)
Test 3 M1 M2
Test 4 M3 M4 M5
M1
M3
M2
M4M5
Out-of-planeswirl compensation
Out-of-planeswirl compensation
In-planeswirl elimination
Real world conditions; flow with swirl (scale 5%)
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-5,00
-4,00
-3,00
-2,00
-1,00
0,00
1,00
2,00
3,00
4,00
5,00
0 2000 4000 6000 8000 10000 12000%
m3/h
rejected on irregular baseline behavior
In-plane swirl elimination
70
Real world conditions; flow with swirl (scale 5%)
Test 3 M1 M2
Test 4 M3 M4 M5
Out-of-planeswirl compensation
KROHNE V12
M2
M4
M1
M5
Summary
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Summary
swirl
The KROHNE ALTOSONIC V12 is the only ultrasonic gas flow meter that measures within
custody transfer limits even under very strong swirl conditions.
Flow profile scan at five levels Swirl elimination in each measuring plane
-2,00
-1,00
0,00
1,00
2,00
0,00 2000,00 4000,00 6000,00 8000,00 10000,00 12000,00
%
KROHNE V12
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Southstream countries involved
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Southstream facts / Timeline
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Southstream gas measurement
Russian terminal (near Anapa)
4 measuring lines 16, each 2 UFM in series, ANSI2500 pressure rating
Bulgarian terminal (near Varna)
4 measuring lines 16, each 2 UFM in series, ANSI2500 pressure rating
74
Performance of an out of plane swirl meter in an official AGA9 meter run
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Performance of an out of plane swirl meter in an official AGA9 meter run.
Bill FrasierCeesi Ultrasonic Workshop
Colorado Springs 2011
10D
Flow
straightener
Out-of-planeswirlcompensating
meter
The official recommendedAGA meter run
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Real conditions: CFD of header with 2 Tees
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Real conditions: CFD of header with 2 Tee s.
Courtesy:CFD: Computational Fluid Dynamics
Comment fromCPA:
The CPA platetakes
approximately95% of the swirl.
But there is stillsome swirlremaining!
This results in asubstantial shift
of the metererror.
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Real conditions: CFD of header with 2 Tees
Courtesy:CFD: Computational Fluid Dynamics
Comment fromCPA:
The CPA platetakes
approximately95% of the swirl.
But there is stillsome swirlremaining!
This results in asubstantial shift
of the metererror.
No straight lines!
There is stillsome swirlpresent.
Flow pattern in the north run in the field; clockwise deposit
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p ; p
Flow pattern in the south run in the field; counter- clockwise deposit
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p p
Measurement error of the out-of-plane swir l compensating meter.
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p p g
Conclusions on swirl
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Meters having their swirl compensation not in the same plane of
measurement are very vulnerable to high swirl levels such as can beencountered in real world conditions.
Even if its design is theoretically compensating for a certain swirl type, slight
asymmetries in the flow can result in large measurement errors. Therefore
out-of-plane designs should always be installed with a flow conditioner,
reducing the swirl.
Even when mounted into an official AGA9 meter run, including a flow
straightener, the additional measurement error of an out-of-plane meter is still
in the order of 0.3% to 0.4%. This means that the highest attainable OIM
Class for such meters is Class 1.
Only by in-plane swirl correction the impact of swirl can be totally cancelledout and an OIML classification 0.5 can be achieved using 5 measurement
planes.
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Final path configuration
Velocity profi le changes
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2 stable profile
supports at 0.5R
85
Flow profile correction with KROHNE
3additional
pathsfor
correctingthe impact
ofprofile
distortions
ALTOSONIC V12; The Power of Reflection
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Item Benefit Drawback
Doubling the pathlength
Higher accuracy less suitable forhigh CO2
applications
more powerful
transducers
Swirl In the plane swirl
elimination.
none
Multipoint
interrogation of the
pipe wall
Detection of fouling
Assuring
measurement
quality
(expert system)
none
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OIML R137
ALTOSONIC V12: the onlyUSM within class 0,5
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Transducer selection
Transducers
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. There is not a one-first-all solution.
. Transducers have to be chosen dependent on the application.
Key selection cri teria:
pressure range
temperature range
chemical resistance
acoustic attenuation
control valve noise
Transducer design
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90
Various types of designs and frequencies:
Epoxy based:
excellent acoustic and chemical properties
Temperatures -50 C t/m 100 C
pressures up to 500 bar
Full Titanium:
Temperatures - 40C t/m +180C
Pressures up to 150bar@180C
Wave guides for higher temperatures
& special applications
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91
Titanium transducer for wet gas and high temperatures
Appl icat ion chart
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92
ApplicationTransducer type
Dry natural gas Wet gas Sour gas Methanol Hightemperature
Highpressure
Epoxy ++ - + - ++
Full Titanium + ++ + H2O>10%
++ +
Wave guide(non custody transfer) - - +/- + ++ ++
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93
Frequency selection:
Valve present: high frequency.
CO2 / low pressure: low frequency.
Absorption of the acoustic pulse (by CO2)
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94
CO2 is a symmetrical molecule.
It resonates within a specific frequency band and thereby takes a lot ofenergy away from the acoustic pulse.
CO2 Theoretical absorption curves
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95
The attenuation coefficient is almost constantbetween 80 kHz and 1 MHz
CT Products
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96
Attenuation equation:
In this equation:
C is a constant depending on the transducer efficiency
L is the path length.
is the attenuation coefficient (almost constantbetween 80 kHz and 1 MHz)
Therefore the path length is the determining factor !
100%100
100% 2lg22 COCOL
transducer
asnaturaCO
eLCP
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CO2 tests: Test set up
97
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CO2 tests: Primary results
98
~1
~
~%
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CO2 tests: Attenuation factor
99
4 meter, minimum pressure requirements
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100
1.0 2.0 4.0 8.1 16.332.7
65.5
130.9
261.1
519.2
1029.2
0.5 0.71.0
1.42.0
2.8
4.0
5.7
8.0
11.3
15.8
0.0
200.0
400.0
600.0
800.0
1000.0
1200.0
0.0 20.0 40.0 60.0 80.0 100.0 120.0
%CO2
p
ressure[bar]
0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
Re f lect i ve pat h Di rec t pat h
4 inch
6 meter, minimum pressure requirements
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101
0.8 2.0 5.2 13.5 34.888.6 224.7
566.8
1424.0
3563.8
8889.4
0.4 0.6 1.11.9 3.3
5.7
9.7
16.4
27.5
46.1
77.0
0.0
1000.0
2000.0
3000.0
4000.0
5000.0
6000.0
7000.0
8000.0
9000.0
10000.0
0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0%CO2
pressure[bar]
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
Ref lect ive path Di rect path
6 inch
8 meter, minimum pressure requirements
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102
8 inch
5 11 23 51 110237 512
1107
2391
5163
11141
2 35
811
17
25
38
56
84
125
0.0
2000.0
4000.0
6000.0
8000.0
10000.0
12000.0
0.0 10.0 20.0 30.0 40.0 50.0 60.0
%CO2
pressure[bar]
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
Re f lect i ve path Di rect path
10 meter, minimum pressure requirements
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103
10 inch
7 14 27 53106 210
417
827
1639
3249
6436
3 46
913
18
26
37
53
75
107
0.0
1000.0
2000.0
3000.0
4000.0
5000.0
6000.0
7000.0
0.0 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0
%CO2
pressu
re[bar]
0.0
20.0
40.0
60.0
80.0
100.0
120.0
Ref lect ive path Direct path
Altosonic V12-D
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104
Conclusions on CO2 .
Path length is the dominant factor whether a meter will
function or not.
The calculation model can predict the performance at the
quotation level.
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The impact of fouling and the
diagnostic Expert System
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106
Inlet 12 piping
Bill Frasier Ceesi, Ceesi ColoradoSprings Ultrasonic Workshop 2011
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107
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108
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109
The straight path meter could not detect this shift !
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110
Clean and dry gas applications?
Clean dry gas ?
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111
IHSM pictures on fouling
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112
Variations in fouling
1. Liqu id layer on the bottom of the pipe (condensates, water, spi ll-over)
2. Asymmetrical fouling (wax deposits)
3. Symmetrical wall build-up (black powder)
4. Dirt build-up on the transducer (wax)
5. Liquid contamination in the transducer ports
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113
Examples of Fouling
1: Fouling as a small flow on the bottom of the pipe
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114
Variations in fouling
1. Liquid layer on the bottom of the pipe (condensates, water, spill-over)
2. Asymmetr ical foul ing (wax deposi ts)
3. Symmetrical wall build-up (black powder)
4. Dirt build-up on the transducer (wax)
5. Liquid contamination in the transducer ports
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115
Examples of Fouling
Original clean situation
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116
Examples of Fouling
2: Fouling, asymmetrical stuck to the pipe wall
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117
Variations in fouling
1. Liquid layer on the bottom of the pipe (condensates, water, spill-over)
2. Asymmetrical fouling (wax deposits)
3. Symmetrical wall build-up (black powder, corrosion)
4. Dirt build-up on the transducer (wax)
5. Liquid contamination in the transducer ports
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119
Variations in fouling
1. Liquid layer on the bottom of the pipe (condensates, water, spill-over)
2. Asymmetrical fouling (wax deposits)
3. Symmetrical wall build-up (black powder, corrosion)
4. Dirt build-up on the transducer (wax)
5. Liquid contamination in the transducer ports
4. Dirt bui lt-up on the transducer.
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120
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121
Variations in fouling
1. Liquid layer on the bottom of the pipe (condensates, water, spill-over)
2. Asymmetrical fouling (wax deposits)
3. Symmetrical wall build-up (black powder)
4. Dirt build-up on the transducer (wax)
5. Liquid contamination in the transducer ports
5. Liquid contamination in the transducer pockets.
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122
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123
Testing in Lintorf
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124
Testing in Lintorf , 2 x ALTOSONIC V12, 6
Performance Monitoring: Symmetrical wall buil t-up
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125
18 observation points
3. Fouling of evenly d istributed inside the pipe.
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126
Expected diagnostic key indicators:
Irregular changes in the Speed of Sound as well as the Reflection coefficient (trending)
3. Fouling of evenly distributed inside the pipe; the velocity profi le
8 0%
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127
The flow velocity profile is much sharper.
-14.0%
-12.0%
-10.0%
-8.0%
-6.0%
-4.0%
-2.0%
0.0%
2.0%
4.0%
6.0%
8.0%
-1.00 -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 1.00
fouling
clean
3. Fouling of evenly d istributed inside the pipe; the reflection coefficient .
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128
The signal strength varies with the thickness of the layer.
Signalstrength
60.0
62.0
64.0
66.0
68.0
70.0
72.0
74.0
76.0
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00
GAINAB3
GAINAB6
GAINAB3
GAINAB6
GAINAB1
GAINAB2
GAINAB3
GAINAB4
GAINAB5
GAINAB6
Change in signal strength on the reflecting paths
6
3
3. Fouling of evenly d istributed inside the pipe.
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129
There is are irregular changes in the standard deviation; both thethickness of the layer and the surface roughness have an effect.
Standarddeviation
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
0.50
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00
SDCh_SoS[3]
SDCh_SoS[6]
SDCh_SoS[3]
SDCh_SoS[6]
SDCh_SoS[1]
SDCh_SoS[2]
SDCh_SoS[3]
SDCh_SoS[4]
SDCh_SoS[5]
SDCh_SoS[6]
Change in the SOS standard deviation of the reflecting paths
6
3
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3. Fouling of evenly d istributed inside the pipe; error curve
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131
Evenly fouling
-0.20
0.00
0.20
0.40
0.60
0.80
1.00
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00
base downstream
evenly fouling
First order correction using GC data as input
Meter
error
Using information of a GC to calculate the SOS, a goodcorrection is possible with an uncertainty of 0.1% - 0.15%.
Performance Monitoring: Bottom fouling
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132
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133
Applying th in str ip of regular grade anti -seize lubricating compound
meter
Inlet pipe
1 Fouling on the bottom; the velocity profi le
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134
-12.0%
-10.0%
-8.0%
-6.0%
-4.0%
-2.0%
0.0%
2.0%
4.0%
6.0%
8.0%
-1.00 -0.80 -0.60 -0.40 -0.20 0.00 0.20 0.40 0.60 0.80 1.00
1. Fouling on the bottom; the velocity profi le
The changes in the flow velocity profile are so minimal, that it cannot be used as an indicator !!
Fouling
With fouling
clean
Gasflow
1. Fouling on the bottom: change in reflection coefficient
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135
With thin layers, the fouling has hardly any impact on the signal strength.
60.0
62.0
64.0
66.0
68.0
70.0
72.0
74.0
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.0
Signal strength with and withoutbottom fouling
1. Fouling on the bottom: standard deviation wi th and without bottom fouling
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136
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.0
Path 3
Path 6
6
3
The standard deviation of the path reflecting at the bottom increases with increasing fouling
1. Fouling on the bottom; change in the SOS of path 6
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137
SOS comparison; bottom fouling
-0.30%
-0.20%
-0.10%
0.00%
0.10%
0.20%
0.30%
0.40%
0.50%
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00
m/s
%d
ifference
SOS change in path 6
1. Fouling on the bottom; error curve
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138
Bottom fouling
-0.20
0.00
0.20
0.40
0.60
0.80
1.00
0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00
m/s
%
error
base downstream
bottem fouling
First order correction
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Many more fouling tests done, such as
139
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140
Key diagnostic indicators
Velo
city
pro
file
Footp
rint
refle
ctio
ncieffic
ient
sig
nals
treng
th
sta
ndard
deviatio
n
ignalto
nois
e
SOS
Bottom fouling X X X
A-symmetrical f ouling X X X
(wax deposits)
Symmetrical fouling X X X X X
(black powder)
Fouling on transducers X X
(wax deposits)Liquid contamination in the transducer pockets X
(water & condensates)
All the dif ferent ways of fouling are clearly detectable!(simplified diagram)
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Krohne
the Diagnostic Expert System
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142
Diagnostic Expert System
It is much more than Condition base Monitoring
IDENTICAL
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Condition Based Monitoring
|31 143
C diti B d M it i
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144
Condition Based Monitoring
Definition:
Maintenance when need arises
What you need is
Predictive Monitoring!
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Expert System
|31 145
an expert system is a
computer system that emulates
the decision-making ability of a
human expert
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146
Diagnostic Expert System
Elements in the design:
Maintenance BEFORE the need arises
Based on experimental & Analytical/numerical investigations
Based on real time data and historical data
Sophisticated software presenting Expert diagnostics
We have asked our people how to diagnose problems
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147
We have asked our people how to diagnose problems
Bottomfouling
Asymmetrical fouling
Symmetrical fouling
Transducer fouling
Profile distortion
Trend analysis
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We put our intel ligence
148
into the meter
KROHNE C Th hi h l l f di i
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149149
PGC
T-transmitter3144
P-transmitter3051
KROHNE Care
INTERNET
TCP/IP
HART
Modbus
- The highest level of diagnostics
TCP/IP
KROHNE C t t
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KROHNE Care expert system
150
Predictive maintenance
by trending
Expert system
Di ti E t t Ab l t M it i
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151
Diagnostic Expert system: Absolute Monitoring
Abso lut e Monit ori ng (Tren d)
0
20
40
60
80
100
120
Time
PulseAcceptance[%
]
Di ti E t t R l ti t P th M it i
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152
Diagnostic Expert system: Relative to Path Monitor ing
Diagnostic E pert s stem Velocit Dependent Monitor ing
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153
Velocity dependant Monitoring
0
0.05
0.1
0.15
0.2
0.25
0 5 10 15 20 25 30
Velocity [m/s]
StandardDeviationSoS
SDSoS1
SDSoS2
SDSos3
SDSoS4
SDSoS5
SDSoS6
Diagnostic Expert system: Velocity Dependent Monitor ing
Diagnostic Expert system: Application Dependent Monitoring
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154
Diagnostic Expert system: Application Dependent Monitoring
Gas Composition
Temperature Calculated SoS
Pressure
Measured SoS
Diagnostic key parameters
Available key information:
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155
Available key information:
Parameters
Flow velocity for six paths Speed of Sound for six paths Pulse acceptance for six paths Amplification for 12 transducers S2N for 12 transducer
Values: For each parameters Live, Average, Standard Deviation, Minimum & Maximum
Parameter checks:
AbsoluteRelative per pathVelocity dependent
Addi tional:For each parameter Historical application specific reference data.
Total
42
x
5210
x3
630
(1260)
Fl fil O ti lSOS
Relationship between diagnostic parameters is complex.
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156
SD Vg
Evenly fouling
Approval
Bottom fouling
Materials
Gunk
Condensate
NoiseWall roughness
Trending
Black powder
FAT
Flow profile
Measuring points
Asymmetrical fouling
Calibration
CO2
SD SOS
Signal strengthP
T
Gas composition
Pulsation
Operating envelope
Reflectioncoefficient
Footprint
Inlet conditions
Flow conditioner
Signal to noise ratio
Thats why KROHNE Care has been designed
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157
That s why KROHNE Care has been designed
To detect failures automatically
To propose measures
To check 24/7
To validate your CT
measurement
KROHNE Care WEB server built in
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158158
KROHNE Care - WEB-server built-in
KROHNE Care WEB server built in
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159159
PGC
T-transmitter
3144
P-transmitter3051
KROHNE Care
INTERNET Ethernet
HART
Modbus
- WEB-server built-in
Diagnostic Expert system (data)
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160
Diagnostic Expert system (data)
Multiple variables
SoS, V, GAIN, S2N, PulseAccept.
Multiple monitoring types
Absolute, Relative,
Velocity & application dependant
Multiple values
Average & Standard Deviation.
Reference data
Multiple Quality Checks
Quality Status
Overall status
Diagnostic Expert system (software)
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161
Multiple Quality Checks
Quality Status
Overall status
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And has been working f ine over
the whole passed period
This meter works f ine, no issues expected
ALTOSONIC V12 web page: Expert system
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163
Warning;meter still ok, but corrective action requiredEvent
Reason for warning
ALTOSONIC V12 web page: Expert system
ALTOSONIC V12 web page: Diagnost ics
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164
Reason for warning
ALTOSONIC V12 web page: Diagnost ics
ALTOSONIC V12 web page: Live data
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165
ALTOSONIC V12 web page: Live data
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166
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167
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168
ALTOSONIC V12 web page: report ing (full ISO 17089 compl iance)
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p g p g ( p )
169
ALTOSONIC V12 web page: Data upload & download
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p g p
170
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CONCLUSIONExpert System
171
Reflective Technology Detection of fouling
Complex and fast increasing amount of data requires understandable solutions
Expert system: KROHNE Carewith features:
24/7 Diagnosis by Expert System Remote control by web based functionality Flow computer functionality
To assure your billing is correct!
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Verification of ultrasonic flow meters
In situ verification possibil ities
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Reference values:
Factory acceptance test
High pressure flow calibration
Possibilities for in situ verification:
1. In situ verification by the meter itself: expert system.2. In situ verification by comparing the SOS calculated and measured
in compliance with AGA Report No. 8 or 10.
3. 2 meters in series
4. Master meter design
Reference values: Factory Acceptance Test (FAT)
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Zero flow condition
Pressurized (appr. 150psi)
Filled with 100% Nitrogen
P&T measured
SOS calculated (AGA10)
SOS compared
Path length check
Path angle check
Functional test
Second set of reference values: Flow calibration
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High pressure
Natural gas
Typically 6 flow rates
1: In situ verification by the meter itself:
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The diagnost ic expert system.
Sensitivity:0.1%-0.3%on fouling
2: Speed of Sound comparison.
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gas composition
actual flow
TP
Can also be done as part of
the Expert system.
Sensitivity:0.1 - 0.2% on SOS
3: Two meters in series
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Ultrasonic meter and turbine meter
Commonly done in Europe for border stations.
Ultrasonic meter and ultrasonic meter
Common practise in Europe for bi-directional measurement
Sensitivity:2* OIML class +
0.2-0.3% for fouling
4: Master meter (Z-bridge)
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100% duty meter
Comparison between
duty meter (possibly
contaminated) and clean
mastermeter
Comparison on a
periodic base
Master meter (Z-bridge)
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100% duty meter
Comparison between
duty meter (possibly
contaminated) and clean
mastermeter
Comparison on a
periodic base
Sensitivity:2* OIML class
Master meter (Z-bridge)
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2x 50% duty meter Comparison between duty
meter (possibly
contaminated) and cleanmastermeter
Comparison on a periodic
base
In reflection
In reflection
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182
There are things that we know
There are things that we dont know
There are things of which we know that we dont know.
There are things that we dont know that we dont know.
The same is true with the measurement under fouling
conditions.
In reflection
If you use a straight path non reflecting design:
In reflection
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y g p g g
you know that there might be fouling
you dont know if there is any fouling
you know that you dont know when there is any fouling
you dont know that you dont know what hits you
However, using a reflective design:
you know that there might be fouling
you know if there is any fouling
you know that you know when there is any fouling