EVALUATION OF SONAR CLAMP-ON FLOWMETERS FOR · PDF fileevaluation of sonar . clamp-on flowmeters for . ... and downstream of 4” orifice, ... evaluation of sonar clamp-on flowmeters

DOC ID© Chevron 2005

EVALUATION OF SONAR CLAMP-ON FLOWMETERS FOR WET GAS FLOW MEASUREMENT

Presented at the 2007 Multiphase Metering Roundtable (MMR), Galveston, TexasApril 26-27, 2007

ByFrank Ting, Chevron ETC, Houston, TexasDaniel L. Gysling, CiDRA, Wallingford, CT


Outline

•Introduction—clamp-on devices for flow measurement

•SONARtrac™ meters performance evaluation tests

•Dry flow performance tests results

•Wet flow performance test results

•Flow measurement uncertainty/repeatability

•Conclusions


Commercial Clamp-on Devices for Flow Measurement

Fluid Metering principle

Single Phase – Gas Ultrasonic, sonar

Single Phase -Liquid

Ultrasonic, sonar

Two Phase -Bubbles (low GVF)

sonar

Two Phase – Wet gas (High GVF)

sonar

Multiphase nucleonic


Clamp-on SONARtrac™ Gas Flow Meter

SONAR Algorithms Identify Ridge

Slope yields flow rate

6 inch Sonar Meter Perfromance

0

5

10

15

20

25

30

35

0 5 10 15 20 25 30 35

Reference Velocity, fps

Mea

sure

d V

eloc

ity, f

ps

Slope of Ridge Determines Flow rate

Slope of Convective Ridge:

27 fps


5 fps


17 fps

6 inch Sonar Meter Perfromance

0

5

10

15

20

25

30

35

0 5 10 15 20 25 30 35

Reference Velocity, fps

Mea

sure

d V

eloc

ity, f

ps

Slope of Ridge Determines Flow rate


27 fps


27 fps


5 fps


5 fps


17 fps


17 fps


17 fps


Clamp-on Device for Flow Measurement

Advantages

•No pressure drop

•No pipe wall penetration

•Portable

•Lower cost

Challenges-- multiphase fluid measurement

•Improve performance uncertainty

•Widen operation range


Meters Evaluation Tests

•Chevron and CiDRA tests SONARtrac™ Gas Flow Meter

•Test conducted at the Colorado Engineering Experiment Station, Inc., (CEESI) Wet Gas Flow Facility, Nunn Colorado, USA in April 2006

•Sonar meters were mounted (4” Sch 40) upstream and downstream of 4” orifice, cone-type and venturi in series


SONARtrac™ Meters Performance Testing in CEESI Wet Gas Flow Loop


Metering System Test Conditions

•Pressures at 600, and 1,100 psig

•Dry gas and wet gas with liquid- gas flow ratio up to 150 bbl/MMSCF (Lockhart-Martinelli Numbers= 0, 0.002, 0.005, 0.01, 0.015, 0.02, 0.03, 0.05, 0.1, 0.15, and 0.2)

•Gas velocities at 20,40, 60, and 80 feet/sec at the four-inch pipe


SONARtrac™ and Orifice Meter


Definitions

Lockhart Martinelli Number (LM) is defined as:

Meter Deviation from Reference (%)

= ( meter reading - Reference) / Reference *100%

m&

g

l

g

l

Q

Q

AloneFlowingGasofInertiaAloneFlowingLiquidofInertia

LM

ρρ

.

.

=

=

m& m&m&


Typical Fluid Properties

•Gas:

Lean natural gas (density=2.05 lbm/cu ft)

•Liquid:

Stoddard solvent (C10, C11 and C12 with density=45.6 lbm/cu ft)


Examples of Liquid Gas Ratio with respect to Lockhart Martinelli Numbers

Lockhart MartinelliNumber

Pressure, psia

Gas Density,lb/cu ft

Liquid Density, lb/cu ft

Gas Void Fraction

Liquid Gas RatioLGR

bbl/MMSCF

0.02 3,000 12.5 37.5 0.9886 8

0.02 750 3.1 37.5 0.9943 17

0.02 150 0.6 37.5 0.9975 43

0.3 3,000 12.5 37.5 0.85 118

0.3 750 3.1 37.5 0.92 262

0.3 150 0.6 37.5 0.96 649


Dry Test (LM=0) Results

SonarTrac vs Reference at dry condition- 600 psi Run 06CVR017 April11 06 CEESI

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

10.0

0 5000 10000 15000 20000 25000 30000 35000 40000 45000 50000

Reference Flow Rate (lbm/hr)

Sona

rTra

c De

viat

ion

from

Ref

eren

ce (%

Orifice UpOrifice DownV Cone UpV Cone DownVenturi UpVenturi Down


Dry Test Results Comparison

Dry Gas Test Points - CEESI Apr '06Calibrated VF Error

Using Standard Water-based Cal Coefficients

-2.0%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

12.0%

0.00E+00 2.00E+06 4.00E+06 6.00E+06 8.00E+06 1.00E+07 1.20E+07

Reynolds Number

Volu

met

ric F

low

Standard Cal -600 psi

Standard Cal 1000 psi

No Calibration - 1000 psiNo Calibration - 600 psi

Standard Calibration

4" Sch. 80 Pipe

Average Out-of-the-Box offset +0.67%


Meter Installation Tests

SonarTrac Gas Sensitivity on Wetness--600 psi and 73 fps 06CVR018 Apr 11 06 CEESI

-2.0

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

0.000 0.020 0.040 0.060 0.080 0.100 0.120 0.140

Lockhart-Martinelli Number (LM)

Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

eren

Flow

(%)

Orifice Up

Orifice Down

V Cone Up

V Cone Down

Venturi Up

Venturi Down


Meter Wet Gas Performance Tests

Gas Reading of Calibrated SonarTrac at Upstream of Orifice Meter 0.68 beta - 600 psi

Apr 11-12 06 CEESI

-15.0

-10.0

-5.0

0.0

5.0

10.0

15.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

eren

Flow

(%) Vg=73 fps

Vg= 58 fpsVg= 40 fps

Vg=20 fps



Gas Reading of Calibrated SonarTrac at Upstream of Cone Meter 0.75 beta - 600 psi

Apr 11-12 06 CEESI

-15.0

-10.0

-5.0

0.0

5.0

10.0

15.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

ere n

Flow

(%) Vg=73 fps

Vg=58 fps

Vg= 40 fps

Vg=20 fps



Gas Reading of Calibrated SonarTrac at Upstream of Venturi 0.6 beta - 600 psi

Apr 11-12 06 CEESI

-15.0

-10.0

-5.0

0.0

5.0

10.0

15.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

ere n

Flow

(%) Vg=73 fps

Vg=58 fps

Vg= 40 fps

Vg=20 fps



Gas Reading of Calibrated SonarTrac at Upstream of Orifice Meter 0.68 beta - 1100 psi Apr 12-13 06 CEESI

-5.0

0.0

5.0

10.0

15.0

20.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

eren

Flow

(%)

Vg=78 fps

Vg=60 fps

Vg= 40 fps

Vg= 20 fps

Vg= 10 fps



Gas Reading of Calibrated SonarTrac at Upstream of Cone Meter 0.75 beta - 1100 psi Apr 12-13 06 CEESI

-5.0

0.0

5.0

10.0

15.0

20.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

ere n

Flow

(%)

Vg=78 fps

Vg= 60 fps

Vg=40 fps

Vg=20 fps

Vg=10 fps



Gas Reading of Calibrated SonarTrac at Upstream of Venturi 0.6 beta -1100 psi

Apr 12-13 06 CEESI

-5.0

0.0

5.0

10.0

15.0

20.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

eren

Flow

(%)

Vg= 78 fps

Vg=60 fps

Vg= 40 fps

Vg= 20 fps

Vg= 10 fps


SONARtrac™ Measurement Uncertainty

Gas Reading of Calibrated SonarTrac at Upstream of Metering Devices600 psi

Apr 11-12 06 CEESI

-15.0

-10.0

-5.0

0.0

5.0

10.0

15.0

20.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

ere n

Flow

(%)

Vg/o=73 fps

Vg/o= 58 fps

Vg/o= 40 fps

Vg/o=20 fpsVg/o=73 fps

Vg/c=58 fps

Vg/c= 40 fps

Vg/c=20 fpsVg/v=73 fps

Vg/v=58 fps

Vg/v= 40 fps

Vg/v=20 fps


SONARtrac™ Measurement Uncertainty

Gas Reading of Calibrated SonarTrac at Upstream of Metering Devices 1100 psi

Apr 12-13 06 CEESI

-15.0

-10.0

-5.0

0.0

5.0

10.0

15.0

20.0

0.000 0.050 0.100 0.150 0.200 0.250


Cal

ibra

ted

Sona

rTra

c G

as F

low

M

easu

rem

ent D

evia

tion

from

Ref

ere n

Flow

(%)

Vg/o=78 fpsVg/o=60 fps

Vg/o= 40 fps

Vg/o= 20 fpsVg/o= 10 fps

Vg/c=78 fps

Vg/c= 60 fps

Vg/c=40 fpsVg/c=20 fps

Vg/c=10 fps

Vg/v= 78 fpsVg/v=60 fps

Vg/v= 40 fps

Vg/v= 20 fps

Vg/v= 10 fps


Conclusions

• Dry gas flow calibration is recommended before placing in service to reduce flow metering uncertainty

• Wet gas flow measurement uncertainty is in the range of ±5% when gas velocity is greater than 20 feet per second

• Mount meter on the upstream piping of a differential device, valve, or bends

• SONARtrac™ gas meter can be coupled with a differential device to measure gas and liquid flow rates. Liquid flow rate measurement uncertainty is larger than the gas flow rate uncertainty.


Wet Gas Measurement using Combination of SONAR and DP Meter


Wetness causes differential pressure based flow measurements devices to over-report gas flow rates

SONARtrac™ provides a mixture flow rate which is significant less sensitive to wetness

Combination of SONAR plus DP provides gas and liquid flow rates

Combining SONAR plus DP for Wet Gas

WET GASVF offset vs LM# - SONARtrac (TM)

0.95

1.00

1.05

1.10

1.15

1.20

1.25

1.30

1.35

1.40

1.45

0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35

Lockhardt-Martinelli Number

Test#5 300 psi 50 ft/sTest#7 1000psi 50 ft/sTest#10 1000psi 80ft/s Test#11 1000psi 50ft/s Historical Data: Orifice PlateHistorical Data: V-Cone MeterHistorical Data: Venturi Meter

SONARtrac™

Δ provides wetness


Theoretical Over Report

For Well Mixed Flows through a DP Device:

LMLGMRQQ

QQQ

ORliq

gas

liq

gas

gas

liq

gas

gasliqSONAR ρ

ρρρ

+=+=+=+

≈ 111

LGMRmm

PP

ORgas

liq

dry

wetDP +=+≈

ΔΔ

= 11&

&

For Well Mixed Flows through a SONAR Meter


SONARtrac™VF-100

SONAR plus DP System ArchitectureFor Wet Gas Measurement

Flow

Flow Computer

Wetness Sensitivity

Wetness

OR

Device Characterization

DP

Gas Rate

Liquid Rate

http://www.kimark.com/images/products/e-chart-gas-meter-lg.jpg


Venturi and SONAR OverReport Due to WetnessApril 2006

-0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

0 0.2 0.4 0.6 0.8 1 1.2

Liquid to Gas Mass Ratio

Ove

r Rep

ort

Venturi - 600 psiSONAR - 600 psiVenturi - 1100 psiSONAR - 1100 psiVent=.67 LGMR - .257 LGMR^2SONAR= 0.05 LGMRVenturi TheorySONAR 600 psi TheorySONAR 1100 psi Theory

Unpublished Work CiDRA Corporation ©2006



Venturi Plus SONARGas RateApril 2006

0

10

20

30

40

50

60

0 10 20 30 40 50 60

Reference Gas Rate (mmSCFD)

Mea

sure

d G

as R

ate

(mm

SCFD

)

66 ft/sec - 600 psi -- Fr=5.052 ft/sec -- 600 si -- Fr=3.935 Ft/sec -- 600 psi -- Fr=2.618 ft/sec - 600 psi -- Fr=1.3635 ft/sec -- 1100 psi -- Fr=3.670 ft/sec -- 1100 psi -- Fr = 7.255 ft/sec -- 1100 psi -- Fr = 5.6Unity+5%-5%



Gas Rate Error vs LMVenturi Plus SONAR

April 2006

-10.0%

-8.0%

-6.0%

-4.0%

-2.0%

0.0%

2.0%

4.0%

6.0%

8.0%

10.0%

0 0.05 0.1 0.15 0.2 0.25

Lockhardt - Martinelli Number

Erro

r in

Gas

Rat

e

66 ft/sec - 600 psi -- Fr=5.052 ft/sec -- 600 si -- Fr=3.935 Ft/sec -- 600 psi -- Fr=2.618 ft/sec - 600 psi -- Fr=1.3635 ft/sec -- 1100 psi -- Fr=3.670 ft/sec -- 1100 psi -- Fr = 7.255 ft/sec -- 1100 psi -- Fr = 5.6



Liquid RateVenturi Plus SONAR

April 2006

0

500

1000

1500

2000

2500

3000

3500

0 500 1000 1500 2000 2500 3000 3500

Reference Liquid Rate (BPD)

Mea

sure

d Li

quid

Rat

e (B

PD)




Liquid Rate Error vs LMVenturi Plus SONAR

April 2006

-50.0%

-40.0%

-30.0%

-20.0%

-10.0%

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

0 0.05 0.1 0.15 0.2 0.25

Lockhardt-Martinelli Number

Erro

r in

Liqu

id R

ate

66 ft/sec - 600 psi -- Fr=5.052 ft/sec -- 600 si -- Fr=3.935 Ft/sec -- 600 psi -- Fr=2.618 ft/sec - 600 psi -- Fr=1.3635 ft/sec -- 1100 psi -- Fr=3.670 ft/sec -- 1100 psi -- Fr = 7.255 ft/sec -- 1100 psi -- Fr = 5.6



Gas Oil RatioVenturi Plus SONAR

April 2006

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000

0 10000 20000 30000 40000 50000 60000 70000 80000 90000 100000

Reference GOR (scfb)

Mea

sure

d G

OR

(scf

b)



Summary

•SONAR-based Flow meter are well suited for Wet and Dry Gas flows

•SONAR-based flow meters are significantly less sensitive to mixture wetness than DP device

•Combining a Clamp-on SONAR meter with a DP based flow meter can provide full range wet gas flow measurement capability

Documents

EVALUATION OF SONAR CLAMP-ON FLOWMETERS FOR · PDF fileevaluation of sonar . clamp-on flowmeters for . ... and downstream of 4” orifice, ... evaluation of sonar clamp-on flowmeters