V
Modeling a Simple Gas Pipeline
1. Create a new, network.
2. On the Insert tab, click Source.
3. The red highlight around the icon indicates that some required setup data for the source is
missing. Double-click on the icon to open its edit window.
4. Rename the source MySource.
5. Enter a temperature of 60 degF and click Close.
WORKSPACE
HOME
INSERT
FORMAT
6. In the Fluid manager window under the Home tab, create a new fluid by click the green + sign to
add a row.
Click Template and choose Dry Gas
Click OK to create the fluid.
£
□
New fluid
Template: Dry Gas
□PIPESIM
X
*
0
,/
OK
X Cancel
7. Double-click on the newly added line to display the Edit dialog box.
8. Edit the fields to match the entries in the figure below.
1
|4
n
Fluid manager
Fluids
1
1 +]
x
Fluid mapping
Fluid
Gas
Gas ratio type Gas ratio
• fo
OGR
4
Gas ratio unit
STB/mmscf
*
Water ratio type Water ratio
* 0
WGR
Water ratio unit Description
STB/mmscf
1
*
Edit BOfluid
FLUID
Gas
Name:
Save as template
Desenptiort
Properties
Viscosity
Calibration
Thermal
STOCK TANK PROPERTIES
CONTAMINANT MOLE FRACTIONS
WGR
•: 0
STB/mmscf
OGR
•: 0
STB/mmscf
Gas specific gravity:
•
H2 fraction:
□
□
dAPi
: i0
H2S fraction:
N2 fraction:
0.64
Water specific gravity: 1.02
API
C02 fraction:
CO fraction:
6 */
PIPESIM
Close
©
PIPESIM
j
</
Close
9. Close the fluid editor.
10. On the Fluid mapping tab of the Fluid manager window, associate the new Gas fluid with the
source that was created earlier.
4
□
Fluid manager
Fluids
Fluid mapping
Current selection
Weil
Source
MySource
Fluid
[Gas
Override... Gas ratio type
OGR
Gas ratio
0
Gas ratio unit
Water ratio type Water ratio
STB/mmscf
WGR
0
Water ratio unit
STB/mmscf
Gas
11. Close the Fluid Manager.
12. Click the Insert tab.
13. Add a Sink to the network diagram and rename it MySink.
14. Draw a flowline between the source and the sink.
Click Flowline on the Insert tab ribbon, then move the cursor towards the source.
Click MySource, then move the cursor towards the sink. The same signals indicate when the
cursor is in the correct location to anchor the flowline to the object.
Click MySink to terminate the flowline at the sink. The result should match the figure.
2
x
MySource
MySink
FL
«=
15. Double-click on the flowline to open the Flowline properties editor.
16. Enter the flowline data shown in the figure.
Q
□
Edit 'FL'
X
FLOWLINE
Name: FL
<*'ÿ Simple
Mode:
Detailed
Environment
• Land J Subsea
Override global environmental data:
PIPE DATA
Inside diameter
Wall thickness
-:
Roughness:
3.068
in
0.216
in
0.0018
in
PROFILE DATA
Rate of undulations (1/1000): 0
___
: 20000
Horizontal distance
Elevation difference:
1000
Flowline starts at
MySource
LAND HEAT TRANSFER DATA
U Value type:
ft
ft
ik
0
User supplied
•
10000 15000
5000
Horizontal distance (ft)
20000
Btu/(h.degF.ft2)
Heat transfer coefficient 0
Inside film coefficient
-_
Include
Calculate separately
EJPIPESIM
©
J
Close
Note: The heat transfer coefficient is set to 0 to represent a completely insulated (isothermal) pipe and to
effectively ignore temperature changes for this simple example case. In practical situations, the heat
transfer coefficient is always a positive value.
17. Click Close to exit the Flowline editor.
18. On the Home tab, select Simulation Settings.
19. In the Simulation Settings dialog box, click the Flow correlations tab.
20. Enter the correlations as shown below.
3
f
T
O
Flow correlations
<S
□
Simulation settings
Use global
Heat transfer
Erosion/Corrosion
Environmental
Output variables
Advanced
X
User extensions
C Use local
VERTICAL FLOW (MULTIPHASE)
Source:
OLGAS
Correlation:
OLGAS 2017.1 3-Pbase HD
Friction factor: 1
Holdup factor. 1
HORIZONTAL FLOW (MULTIPHASE)
Source:
Baker Jardine
Correlation:
Beggs 84 Brill Revised
Friction factor 1
Holdup factor 1
VERTICAL-HORIZONTAL SWAP ANGLE
Swap angle:
45
deg
SINGLE PHASE
Correlation:
Moody
□PIPESIM
©
21. Click MySource to activate all the possible tasks that can be run, then click
J
Close
P/T profile from the
ribbon on the Home tab (or select the same operation from the Tasks pane).
The Pressure/Temperature Profile operation is used to model the distribution of pressure,
temperature, and other parameters along the flow path.
22. Designate Outlet pressure as the Calculated variable.
23. Enter values for the Inlet pressure and Gas flowrate, as shown in the figure.
24. Set the sensitivity data for Temperature 20, 100, 180 and 260 degF as shown below.
4
b*
□
P/T profile
x
MySource • P/T profile
Nome;
Description
P/T profile
GENERAL
Branch start
MySource
CALCULATED VARIABLE
Iniet pressure
Branch end:
MySnk
•
Default profile p ot Pressure vs. total distance
1200
pua
•
10
rrvmcf/d
•
Outlet pressure
Gas flowrate •
Custom
SENSITIVITY DATA
MySource
Temperature
Range-
o o
Run
□
Reset boundary conditions
Stop
©
PIPESIM
J
25. Run the model.
bfc
□
P/l profile
Name:
x
MySource • P/T profile
Description:
P/T profile
Engine console
System results
Profile results
Snow grid
~
• Showpict
AXES SERIES
Se-ect Bonom X-ars Tcta- d stance
J
Se-ect Left T-aris:
Pressure
J
Select R-gnt Y-a*«
None
ft
ova
P/T praflh : MySource P/T profS*
■
TEMP£SATU«£»20 F Outlet Preuure.TaiCJBS p*» J
TEMPERATURE* 100 F Outer Prewu’e*BM.l0l9 put
TEMPERATURE* 180 F OutM Pretufe*42U6*5 pu*
Run
□
©
PIPESIM
«/ Close
Notice that the highest temperature case generated the highest pressure loss. As the temperature
increases, these conditions change:
•
The density decreases
5
•
The Reynolds number decrease
•
•
The corresponding friction factor increase
The frictional pressure gradient is higher. In other words,
T t » p3 4, » Re =
4, » f
T »
(ÿfriction T
and because
fpv2
(dP\
lid
The velocity increase due to gas expansion has an exponential effect on the frictional pressure term.
This accounts for the increase in the frictional gradient along the flowline and the curvature in the
pressure profile plot.
Note: The viscosity of the gas increases slightly with increasing temperature, but this effect is small
and does little to offset the effects of decreasing density.
Calculating Gas Pipeline Flow Capacity
Previously, the outlet pressure was calculated for a known inlet pressure and flow rate. In this exercise,
you will specify the inlet and outlet pressures and calculate the corresponding gas flow rate.
There are three key variables involved in P/T profile, Nodal analysis, and System analysis tasks:
•
Inlet pressure
•
Outlet pressure
•
Flow rate.
Two of these variables must be specified, and the third is calculated. Some tasks allow you to specify
all three variables, in which case a matching variable, such as pump speed or choke setting, must be
set as the calculated variable.
PIPESIM generally performs calculations in the direction of flow. This means that when the outlet
pressure is calculated, the solution is non-iterative in that the outlet pressure is calculated during the
first and only pressure traverse calculation.
However, when outlet pressure is specified and either inlet pressure or flow rate is calculated, the
process becomes iterative and successive estimates of the calculated variable are supplied until the
calculated outlet pressure agrees with the specified pressure.
6
1. Reconfigure the
P/T profile dialog box. Set Gas flowrate as the Calculated variable with an Outlet
pressure of 600 psia.
2. Delete the sensitivity data from previous exercise.
P/T profile
VyScu-cc • P/T profile
Name
Oescnptorc
P/r profile Engine console
GENERAL
S'ancn start
VySource
8rancnen<t
MySn*
System results
Profile results
Default profile plot Pressure vs. total 0 stance
I
CALCULATED VARIABLE
imet pressuie
Outlet pressure
Gas flovwate
t200
psia
psia
•
Custom
SENSJTIV1TV DATA
Ranqe
1
2
3
4
5
6
7
3
9
10
+
o
Reset boundary conditions
Rui
□
PtPESIM
O I ✓Q«e 1
3. Re-run the task and observe the flow rate that this pipeline is capable of delivering under the
specified conditions.
7
r
n
MySource Name:
Description:
P/T profile
X
P/T profile
Engine console
System results
Profile resuits
Show grid
•
Show plot
Case
1
fplowfite«1071164 nwmcfcT
1
A
AXIS SERIES
Select Bottom X-axis Total distance
Select left Y-aaot
[3 Select Right Y-axis
Pressure
•
ft
•
psia
None
P/T profit* : MySourca • P/T profit*
o o
Run
□
Stop
©
PIPISIM
Calculated Gas flowrate
Oose
(mmscfd)
8
\
Modeling a Multiphase Pipeline
You have explored single-phase flow of gas through a pipeline. In this exercise, you will modify the
existing pipeline model and explore multiphase flow.
1. Use the Fluid Manager in the Home tab to create a multiphase fluid using the properties shown
in the figure.
4
Fluids
!
□
u.d rr
X ■
Fluid mapping
1
Fluid
Gas
2
Multiphase
Gas ratio type Gas ratio
• 0
OGR
*1800
GOR
Gas ratio unit
STB/mmscf
[ SCF/STB
Water ratio type Water ratio
*
WGR
*
Watercut
*
Water ratio unit Descnption
STB/mmscf
0
0
%
+
£
•
_ll _ 1
□
Edit BOFluid
X
FLUID
Multiphase
.Name:
Save as template
I
Description: |
Properties
Calibration
Viscosity
Thermal
STOCK TANK PROPERTIES
Watercut
*:
GOR
• : 800
CONTAMINANT MOLE FRACTIONS
%
-
C02 fraction:
0
SCF/STB
•
H2S fraction:
0
0.64
N2 fraction:
0
Water spec fic gravity: 1.02
H2 fraction:
0
CO fraction:
0
Gas specific gravity.
•
API
□
□
0
-
dAPI
: 30
©
PIPESIM
J
Close
©
PIPESIM
J
Close
2. Click the Fluid mapping tab and ensure that the source is now mapped to Multiphase fluid.
£
□
Fluid manager
Fluids
Fluid mapping
=> Current selection
Well
Source
MySource
Fluid
1
Multiphase
Override... Gas ratio type
GOR
Gas ratio
800
Gas ratio unit
Water ratio type Water ratio
SCF/STB
Watercut
0
Water ratio unit
%
3. From the Home tab choose Simulation Settings.
4. Click the Flow correlations tab and configure the choices for vertical and horizontal flow, as
shown in the figure.
Note: Observe that the Swap angle is set to 45 deg. This is the angle that corresponds to the switch
between using the vertical and horizontal flow correlations. In this example, the pipeline
inclination angle is about 3 deg (that means only the horizontal flow correlation will be used).
9
X
/
r
O
□
Simulation settings
Flow correlations
•
Erosion/Corrosion
Heat transfer
Use global
Environmental
Output variables
Advanced
X
User extensions
Use local
VERTICAL FLOW (MULTIPHASE)
Source:
Baiter Jardme
Correlation:
Hagedom & Brown
Friction factor 1
Holdup factor 1
HORIZONTAL FLOW (MULTIPHASE)
Source:
Baiter Jardme
Correlation:
Beggs & Brill Revised. Taitei DukJer map
Fnction factor t
Holdup factor 1
VERTICAL-HORIZONTAL SWAP ANGLE
Swap angle:
45
deg
SINGLE PHASE
Correlation:
□
Moody
0 J
PIPESIM
Close
5. Reconfigure the P/T profile dialog box, as shown in the figure.
P/T profile
Name:
MySource - P/T profile
Description:
P/T profile
Engine console
System results
Profile results
GENERAL
Branch start
MySource
Branch end:
MySink
Default profile plot Pressure vs. total distance
CALCULATED VARIABLE
Inlet pressure
*
•
4300
psia
10000
STB/d
• Outet pressure
Liquid flowrate
•
Custom
SENSITIVITY DATA
Range.
1
2
3
4
5
6
7
8
9
10
r+
6.
Run the model.
7. From the Profile Results tab, click Show Grid.
8.
Look at the Liquid Holdup or Flow Pattern column. Notice that the flow is initially single-phase
liquid until the pressure falls below the bubblepoint, at which point a two-phase oilgas mixture
evolves. The single-phase Moody correlation is used in the first part of the pipe, and the Beggs
10
and Brill multiphase correlation is used in the second part of the pipe after the pressure falls
below the bubblepoint.
Case
1
2
3
4
_S
6
7
8
9
10
11
>2
13
14
15
16
17
18
19
20
21
Outlet Pressures1044.591 psia
Outlet Pressures 1044591 psia
Outlet Pressure=1044591 psia
Outlet Pressure =1044.591 psia
Outlet °ressure=1044.591 psia
Outlet Pressures 1044.591 psia
Outiet Pressures 1044591 psia
Outlet Pressure=1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044.591 psia
Outlet Pressures 1044591 psia
Outlet Pressures 1044591 psia
Type
Flowline
Rowline
Flowline
Flowline
Flowline
Flowline
Flowline
Rowline
Flowline
Flowline
Rowline
Rowline
Rowline
Flowline
Rowline
Rowline
Flowline
Flowline
Rowline
Flowline
Rowline
Total distance Elevation
ft
ft
0
0
50
1001.249
2002.498
100
3003.748
150
4004.997
5006.246
6007.495
7008.745
8009.994
9011243
10012.49
11013.74
12014.99
1301624
14017.49
15018.74
16019.99
1702124
1802249
19023.74
20024.98
2G0
250
300
350
400
450
500
550
600
650
700
750
800
850
900
950
1000
Pressure
Temperature Fluid mean™
Liquid holdup EVR
psia
degF
ft/s
4800
4648.331
60
61.13792
4498252
4349.658
4202452
4056.542
3911542
376827
3625.749
3484203
3342924
3193.624
3033.91
2861.602
2673.493
2464.507
2232088
1984504
1715.61
1412525
1044591
6226337
633772
64.48019
655731
66.65662
67.73141
68.79812
6935735
70.16521
69.66715
69.1856
68.71855
6826181
6730799
6735218
66.89823
16.70264
16.72483
16.74767
16.77142
16.79621
1632214
16.84935
1637799
16.90823
16.94028
16.99856
17.10465
1724674
17.4406
17.71286
1831202
ia718
19.62967
21.08691
23.68249
29.4639
%
100
100
100
100
100
100
100
100
100
100
66.42305
6538222
65.16859
93.94651
96.61958
94.1089
9134202
8820408
8450182
80.00832
74.63825
67.93261
59.05282
47.63912
1.14181477...
1.14256607...
1.14334588...
1.14415660...
1.14500174...
1.14588522...
1.14681150...
1.14778567...
1.14881353...
1.14990178...
1.15187810...
1.15546713...
1.16025634...
1.16675922...
1.17583097...
1.18900578...
120873267...
123781870...
128294194...
135960935...
151651125...
G-L Pattern
Liquid
Liquid
Liquid
Liquid
Liquid
Liquid
Liquid
Liquid
Liquid
Liquid
Dispersed B
Dispersed B
Intermittent
Intermittent
Intermittent
Intermittent
Intermittent
Intermittent
Intermittent
Intermittent
Intermittent
11
Flow Assurance Considerations
Sa-cz.
In this tutorial, a client with an existing operation in the&ulf uf Mexico has made a new gas condensate
discovery and plans to develop it using four wells producing into a subsea manifold, and then flowing
through a subsea tieback (the pipeline on the floor of the ocean that will "tie" the production from
the new wells to the existing facility) and up a riser to an existing platform. The oil and gas will be
separated on the platform, with the oil pumped to shore and the gas compressed to shore.
Size the subsea tieback and riser
1. Create a new PIPESIM network model/file.
2. Create a compositional fluid with the characteristics listed in the table.
Component
Methane
Ethane
Main Fluid (Mol %)
67.5
5
Propane
2.5
Isobutane
1
1
1
0.5
0.5
10
2.5
Butane
Isopentane
Pentane
Hexane
Water
Carbon Dioxide
C7+(Pet.Fraction)
Methanol
Injection Fluid ((Mol %)
8.5
100
Use the default PVT package (Multiflash), Equation of State (3-parameter Peng-Robinson), and other
model correlations as default.
3. Click New in the Fluid components section to create a new C7+ pseudo-component.
4. Fill in the fields for Name, Molecular weight, Boiling Point and Specific gravity (only), as shown.
H
n
New component
x
GENERAL DATA
Name:
C7+
Type:
•
Molecular weight
115
Boiling point
283.8618
Specific gravity:
0.683
Critical temperature:
574.241
degF
Critical pressure:
294.1559
psia
Acentric factor:
0.4341695
Non hydrocarbon
Hydrocarbon
degF
5. Click OK when complete.
6. In the Fluid manager window, create a new fluid.
12
N
The fluid properties at standard conditions, should be as below
4
□
tdirotMf
x
FLUID
CFluid
Name:
Description:
Composition
Viscosity
Components:
FLASH/TUNE FLUID
Pressure:
Name
Moles
F \i
*4,
mol
1
Water
2
3
Methanol
Methane
10
0
67.5
4
Ethane
5
5
Propane
Isobutane
25
1
6
7 Butane
8 Isopentane
9 Pentane
10 Hexane
11 Carbon Dioxide
12 JC7*
1
n
Mole fraction
• %
Phase ratio:
10
67.5
5
25
1
1
psia
*
Set to standard GOnditiottS
degF
Specify
• Calculate
GOR
•: 7777255
SCF/STB
Watercut
• : 9879613
%
* PHASE COMPOSITIONS
Apply tuned resuits to fluid
=h0.5
05
0.5
25
85
14.69595
Temperature • : 60
Component
Mixture
Gas
Oil
*1
i
05
25
2
3
as
.4
Water
Metnane
Ethane
Propane
0.1
0.675
0.05
5
6
Isobutane
0.025
0.01
Butane
0.01
7
8
Isopentane
0.01
Pentane
9
Hexane
0.005
0.005
10 Carbon Dioxide QX25
0.085
|11 C7*
Water
•
•
0.0002240557
0.005094842
0.002002041
0.003442731
0.01711115
0X141446
0.06013908
0X2981716
0.003419963
0X1171571
0.00472977
0X13259S4
0X1158032
001069866
0.005156526
0.003451298
a(X»495101
0X2499262
0X005284712
003011837
0.9338109
0006067067
0.9999999
217S312E-09
2139929E-12
2596C88E-15
0
0
0
0
0
123C843E-07
0
PHASE PROPERTIES
Parameter
Unit
Mole fraction
Mass fraction
Volume fraction
fract
tract
* 1
• 1
fract
• 1
cP
8
Viscosity
Molecular weight
Density (molar)
Density (mass)
Surface tension (gas-liquid)
9
Surface tension fnas-o-ll
1
2
H3
(4
5
6
7
-I
□
PIPESIM
■
fW-
« mm
U«
, IIM..
■
Mixture
■
f
•
28.7871
lb-moie/ft3
lbrn/ft3
•
0X03190507
•
0X9184542
dyne/cm
•
rtvne/cm
• 6719035
78.98295
Oil
0X8564165
Gas
0X285551
03329213
06133823
0X007213457
05188829
111.9063
03737924
4238925
0X991996
0X1072134
2131119
f
~~
Q002645628
0X5638148
Water
0.08580329
0.0536964
7.907885E-05
1093773
18X152
3.46181
6236521
lP }//////, II y
■
-
y/y/y/i
0 */
13
Cose
7. In the subsequent steps, you will construct a PIPESIM model to replicate the network in the
following figure.
o
Riser
Subsea Manifold
r
—o—
subsea Tieback
8. Enter the data for the Subsea Manifold as in the following figure.
□
'O Edit 'Subsea Manifold'
x
SOURCE
Name:
Subsea Manifold
Active:
0
FLUID MODEL
Fluid:
Override phase ratios:
~
□
+ New-
PRESSURE/FLOWRATE BOUNDARY CONDITIONS
□
PQ curve:
■
Pressure:
1500
Temperature:
Liquid flowrate
□
' Edit-
CFluid
PIPESIM
*
psia
•
degF
•
STB/d
•1
©
J Close
Without closing the dialog box for the Subsea Manifold, click once on the Flowline to switch the
dialog box to the flowline editor.
10. Rename the flowline to Subsea Tieback and enter the flowline data, as in the figure below.
9.
14
□
CZ3 Edit "Subsea Tieback'
X
FLOWLINE
Name: Subsea Tieback
•
Mode:
Environment
Simple
•
Land
Detailed
Subsea
Override global environmental data:
PIPE DATA
Wall thickness
Ambient temperature (degF)
10.02
in
• : 0.365
in
Inside diameter.
Roughness:
0.0018
47.936
in
PROFILE DATA
Rate of undulations (1/10C0)_ 0
: 31680
Horizontal distance
ft
Elevation difference:
0
Flowline starts at
Subsea Manifold
Depth at start (MSL):
1600
ft
ft
SUBSEA HEAT TRANSFER DATA
U Value type:
□
•
20000
30000
Horizontal distance (ft)
Heat transfer coefficient 0.2
Inside film coefficient
10000
0
Insulated
Btu/(h.degF.ft2)
Calculate separately
Include
©
PIPESIM
J
Oose
11. Select Detailed for Mode to access the Heat transfer tab.
12. Configure the flowline heat transfer by setting the U Value input as Calculate and specify pipe
coating detail as shown.
□
t=3 Edit Subsea Tieback
X
FLOWUNE
Name: SuDsea Tieoadc
Mode:
Simple
Land
Environment
•
•
Detailed
SuDsea
Override giooai environmental data
General
Heat transfer
THERMAL DATA
U Value input
PIPE COATING DETAILS
Specify
Pipe conductivity.
2601156
Ground conductivity
0.4478
Pipe bunai depth;
•
Calculate
Thermal cond... Thickness
Btu/(h.degF.ft)
Btu/(h.deg... • in
Btu/<h.degF.ft)
in
L-JU 0.15
025
0
PIPESIM
Insuiai-.on
L+J
Overall outside diameter 11-25
□
Description
•
in
Pipe is elevated aoove ground
© l_y Close
13. Without closing the Flowline editor dialog box for the Subsea Tieback, click once on the Riser to
switch to the dialog box for editing it.
14. Rename the riser to Riser.
15. Change the Mode to Detailed and enterthe information on the General tab, as in the figure below.
15
I
Tf
Edit 'Riser'
RISER
Name Riser
Simple
Mode:
Override global environmental data: Z
General
•
Detailed
Heat transfer
PIPE DATA
Inside diameter
Wail thickness
*
Ambient temperature (dcgF)
10.02
in
: 0365
in
Roughness:
0.0018
50
55
60
65
70
in
PLATFORM DATA
Platform height (above waterline): 60
PROFILE DATA
Riser starts at
J
Use as downcomer
•
Distance
Horizontal
Measured
Horizontal dis... Measured dist.. Depth MSL
ft
0
•
2
0
ft
0
800
3
0
1600
1
*
ft
1600
Horizontal distance (ft)
800
0
[+
□
O
PIPtSIM
V Close
16. Click the Heat transfer tab and set the U Value input option to Calculate and enter 1 layer of
insulation as in the figure below:
"E"
□
Edit 'Rise*'
X
RISER
Name Riser
Mode
Ovemde global environmental data:
General
.
Simple
Detailed
Heat transfer
THERMAL DATA
U Value input
Pipe conductivity
PIPE COATING DETAILS
Specify
26.01156
THERMAL DATA - AIR SECTION
Surface temperature:
60
Wind speed
□
PIPESIM
8.439042
• Calculate
Thermal cond— Thickness
Btu/(h.degf.ft)
d Btu/fhdeg..
_i 0.15
1
degF
•i
h/s
•
LB
•
|Insulal orj
025
Overall outside diameter
Description
•
in
11.25
m
0
</
Close
17. Exit the dialog box and save your workspace.
18. Modify the global environmental settings by selecting Home » Simulation settings »
Environmental and change the ambient air temperature to 51.89 F and sea water gradient to
North Sea, as shown in the following figure. These global values will be used for the heat transfer
calculations for the flowline and riser, because we left the Override global environmental data box
unchecked in both the flowline and riser editors.
16
0
□
Simulation settings
Flow correlations
Heat transfer
Erosion/Corrosion
Environmental
Output variables
Advanced
X
User extensions
AIR DATA
degF
Temperature:
51.8
Wind speed:
8.439042
ft/s
Atmospheric pressure: 14.69595
psia
SOIL DATA
Soil type
Clay Soil (moist)
Soil conductivity:
0.4478
Btu/(h.degF.ft)
METOCEAN DATA
Seawater gradient/current North Sea
Depth MSL
Seawater temp. Current velocity
ft
OegF
0
50
100
200
328.034
500
656.168
51.8
51.5
50
482
46.4
1000
402
1500
10 2000
!L 2500
38.9
37.9
373
1
2
3
4
5
6
.
□
7
8
9
44.4
42.98
•
j ft/s
228
2.28
228
228
2.12
1.64
128
0.97
0.62
033
0.33
PIPESIM
© [ V
Close
19. While still in the Simulation settings dialog, click the Flow correlations tab and select the following
flow correlations:
• Vertical flow correlation = Hagedorn & Brown (Duns & Ros map)
• Horizontal flow correlation = Beggs & Brill Revised
Now, design the system based on following criteria and constraints:
•
Design production rate = 14,000 STB/day (normal scenario). The system should be designed
to achieve a maximum rate of 16,000 STB/day (should the wells produce more than expected)
and should simultaneously be able to handle a turn-down scenario, when the production is
expected to drop to 8000 STB/day.
•
•
For all production rates, the arrival pressure at the Sink must not drop below 400 psia.
Available flowline and riser sizes are 7.981 inches (wall thickness = 0.322 inches), 10.02 inches
(wall thickness = 0.365 inches) and 12 inches (wall thickness = 0.375 inches). Flowline and riser
sizes must be the same for all scenarios (i.e. if 7.981" is selected for the flowline inside
diameter, the riser must also have an ID of 7.981") and the erosional velocity limit must not
be exceeded.
The bigger the flowline and riser, the higher the cost, so the objective would be to select
Cost:
•
the minimum diameter sizes that would satisfy the target rate and constraints specified above.
20. Click the Subsea Manifold and select the System analysis task.
21. Select Outlet pressure as the Calculated Variable and enter any value for the Liquid flowrate e.g.
the normal rate of 14,000 stb/d.
22. For the X-axis variable, select System Data as the object, and Liquid flowrate as the variable. Enter
the range of flowrates the design is being done for: 8000, 14000 & 16000 stb/d.
23. Change the Sensitivity configuration to Change in step with Variable 1 by selecting it from the
dropdown menu. Review the topic System analysis properties to understand the differences
between the sensitivity configuration options.
17
I
24. Configure the additional sensitivity variables for the Subsea Tieback and Riser as in the following
figure.
55
System analysts
Name
Subsea Manifcid - System analysis
Description:
System analysis
Branch stait
Subsea Manifold
CALCULATED VARIABLE
Inlet pressure
Branch end:
Sk
• Outlet pressure
GENERAL
Sensitivity configuration: Change in step with Variable 1
Liquid flowrate •
1500
psia
14000
STB/d
Custom
X-axis
Variable 1
Active:
1
*
Insidedia...
•
Liquid flow-
inside dia~
•
Wall thickrv.
*
in
8000
14000
Range-
P in
7.981
1
10.02
12
2
3
16000
4
*7
9
9.
10
+
+
Run
PtPESIM
0322
0365
0375
•
Riser
•
Wail thictti—
1 7.981
10.02
12
• in
|0322
0.365
0375
Variable 7
Active: J
•J
Variable 8
Vanabie 9
Variable 10
Active:
Active:
Active:
J
»|
-
J
J
*
Range-
Ranqein
Variable 6
Active J
Range-
Range-
•
•
Range-
•
Range-
•
-
Range.
Ranqe_
*
.
10
o
Range-
Variable 5
Active: J
VanaWe 4
Active: v
J
*5
5
6
7
8
□
•
Active:
Riser
Subsea Tie-
Ranqe_
Vanabie 3
Variable 2
Active: J
Subsea Tie-
System Data
ST3/d
2
3
J
Reset boundary conditions
Slop
0
<ÿ Close
25. Click Run.
26. Review the System results plot. Why are there no results for some cases?
27. Determine the minimum diameter of the tieback and riser that satisfies the arrival pressure
requirement (i.e. > 400 psia) for all flowrates.
28. Double-click the Systems plot and change the Y-axis variable to display Erosional velocity ratio
maximum.
29. Verify that the selected flowline ID does not exceed the erosional velocity ratio limit of 1.0 for the
expected flow rates. Compare your results with the answers in the following table.
18
Parameter
Value
Selected Tieback and Riser ID based on 400 psia 10.02
arrival pressure constraint, inch
Max. erosional velocity ratio for selected ID
0.755
Minimum arrival pressure for selected ID
963
Maximum arrival pressure for selected ID
1267.3
Selecting Tieback Insulation Thickness
In this task, you will update the model with the tieback and riser ID selected in the previous exercise
and determine the insulation thickness required to maintain the system outside of the hydrate
formation envelope.
The worst case scenario in terms of a hydrate risk, is when the flow rate through the system is the
lowest, in which case, the heat loss will be the greatest. This scenario will be the turndown case of
8000 STB/day.
Do the following:
1. Double-click on the Subsea tieback and enter the inside diameter and wall thickness determined
from the previous sizing task. Repeat this step for the Riser (ID and Wall thickness for Tieback and
Riser = 10.02" and 0.365" respectively).
2. Go to Home » Simulation settings » Heat transfer and check the Hydrate subcooling box. This will
enable the calculation of the hydrate sub-cooling temperature difference, which is the difference
between the hydrate formation temperature and the flowing fluid temperature (i.e. Thyd -Tf). If
this difference is positive, then the fluid is in the hydrate formation region at that location in the
system.
3. Still under Simulation settings, click the Output variables tab and change the Report template to
Flow Assurance. This template includes the important flow assurance variables; specifically the
following hydrate variables of interest.
Hydrate formation temperature (profile variable)
• Hydrate sub-cooling delta temperature (profile variable)
• Maximum hydrate sub-cooling temperature differential (system variable)
4. Save your workspace.
5. Click on the Subsea Manifold and run the P/T profile task with Outlet pressure set as the Calculated
variable and the Liquid flowrate set to the turndown rate of 8000 STB/day.
6. Double-click the Profile results plot and change the Y-axis variable to Hydrate sub-cooling delta
temperature The plot appears as below. With the current insulation thickness of 0.25", is there a
hydrate risk? At what point in the system does the fluid temperature drop below the hydrate
formation temperature?
•
19
I
P/T piofile
Name:
Source.1 P/T profile
Oejcnption:
P/T profile
Engme comole
System results
Profile results
Show gnd
Case
t |Outlet Pressure■126725 pga
*
•
Show plot
AXES SERIES
Seiea Bottom X-arc Total distance
ft
J
Seiea Left Y-a*it
Hydrate suo-cooimg de*ta_
deg?
J
Seiea Right Y eas:
None
P/T profit* : Source.1 • P/T profit*
Total distance (ft): 237207
Run
Hydrate sub-coolmg delta temperature (degF): 2-4.59
Stop
o
QpiPCSIM
V
Close
7. You may also check the hydrate risk from the phase envelope viewer. Click on the Subsea manifold
and on the Home tab, click on Phase envelope. The plot appears as below. Observe how the
calculated flowing P/T profile line intersects the hydrate formation line. As determined in the
previous step, the system drops into the hydrate formation region at approximately ~13,000 ft,
which is somewhere in the long subsea tieback, which has a total length of 31,680 ft. Clearly, the
current insulation thickness of 0.25" is insufficient to mitigate against hydrate formation.
Network schematic
Subsea Marvfdd CElwd
n
Subsea Manifold Cftuid : Phas* envelop* plot
CONDITION
Pressure:
■
1S00
Temperature - ; 176
-
FLUID PROPERTIES
4215373
SCF/STB
Watercut
7.1006
%
PHASE COMPOSITIONS
Component
Mixture
Od
Gas
Water
1
Water
03)03783963
2
3
Methane
Ethane
003952378
00208907
002296931
isopentane
001
002981009
Pentane
9 Hexane
10 Carbon Dioxide
11 C7*
0.005
0005
0025
001573445
001982128
001961481
0.085
0.4226463
0006153884
08436261
005626038
002464511
0006583205
0006068738
0006359162
0002972306
0001950967
0.02961714
001175304
0.9999681
5.901742E06
Butane
0.1
0675
0.05
0.025
0.01
0.01
4
Propane
5
6
7
liebutane
a
n
D*w tow
PT profile
—
Bubble tow
o Cn»cai point
—•
Water bn*
Plain point
—•
k* tow
Inlet condition
—
Hydrate 2 luw
•
•
GOR
*
——
psu
degF
03540485
0.0511568
1.465251E-08
7.721669E-11
2D12683E-13
265794E-13
135478E-15
S334948E-16
0
2.601572E-05
0
PHASE PROPERTIES
Parameter
Unit
1
Mole fraction
tract
•
2
3
Mas; fraction
•
Volume fraction
tract
tract
J
IfariKitv
rO
Mixture
1
1
• 1
■\
Od
0.180976
04151743
01138032
n UCXKT
Gas
0 7241658
052546
08774985
nmwToafl
8. Determine the appropriate insulation thickness by increasing it in 0.25" increments and running
the P/T profile task until the entire system is hydrate-free. Assume the same insulation thickness
must be used on both the tieback and riser.
20
W
0
0
0
n
Note: There is currently no option to sensitize on coating thickness, in this case, insulation thickness,
in any of the tasks. You will have to manually change the insulation thickness in the tieback and riser
objects, and run the P/T profile task repeatedly until the objective is met.
n
P/T profile
Name:
X
Source.! P/T proft'e
•
Description:
P/T profile
£ng-.r»e console
Profile result*
System result!
Sftowgrd
•
Showp'Ot
Case
1
four** Presaxe*i2733ib pstal
AXIS SER'tS
*
Select Bottom X*a*ts Total distance
•
ft
J
Select left V-ans
Hydrate sut>-coo ing delta
•
degF
J
Select Right Y-axis:
None
-
P/T profit : Source.1 P/T prod*
o
□
PIPESIM
«•] Networfc schematic
Phase envelope x
-
Subsea MamfoW Cflud
Subua Manifold
■
-
CFluld . Pha** enyMope plot
CONDITION
Pressure
Temperature
~
:
1500
psu
176
degF
FLUID PROPERTIES
GOR
4215373
SCF/STB
Watercut
71006
%
-
PHASE COMPOSITIONS
Component
Vxtxre
1
Water
2
3
Methane
Ethane
0.1
0.675
005
4
Propane
s
J
isc butane
Butane
Isopentane
e
Pentane
9
Heaane
6
0025
001
001
OOI
0005
0.005
10 Carbon Dronde 0025
11 C7-
— PT profile
Dew hne
Euselefcne
— Cnt-cal
O
pont
—•
Water hot
hash point
—•
0085
Oi
Gas
Water
0303783963
03S40485
0006158884
03436261
03999681
5.901742E-06
03511563
033952378
03208907
032296931
032981009
031573445
031982128
031961481
0.4226463
005626038
002464511
0308588205
0006068738
0006359162
0002972306
0301950967
002961714
0.01175304
1.46525IE-08
7.721669E-11
2312683E-13
2.65794E-13
125478£-15
S334948E-16
0
2601572E-05
0
* PHASE PROPERTIES
<ein*
Inlet condition
Hydrate 2 toe
Parameter
Unit
1 . Mole fraction
Tract
2
Tract
Tract
Mass traction
3 | Volume fraction
4
Is/icmcdv
rP
Gas
W
0.7241653
1
OU
0180976
04151748
1
01138032
08774985
0
0
0
01453047
nmsoxua
0
Mixture
•
1
•
•
\
V/7
062546
Determine the methanol requirement
Assume the flowline and riser have been insulated, but they are under-insulated with only 0.5 inches
of insulation. In this exercise, you will determine the required methanol injection rate to ensure that
hydrates do not form in the system.
Do the following:
21
1. Double-click on the Subsea tieback and enter an insulation thickness of 0.5 " to model the scenario
where it is under-insulated. Click on the Riser and repeat this step.
2. Insert an Injection Point from the Insert tab and place it between the Subsea Manifold and the
Subsea Tieback. Connect the Subsea Manifold to the Injector using a connector. Connect the
Subsea Tieback to the Injector on the left end and the junction J on the right end, as shown in the
following figure.
Sk
6
o
Riser
Subsea ManifokJ
Inj
Subsea Tieback
|
o
3.
4.
5.
6.
7.
8.
9.
10.
11.
a
Click on the Fluid manager in the Home tab. Click on the Component/model settings tab and add
Methanol to the Fluid Components list by checking the box beside it.
Click on the Fluids tab and create a new fluid by clicking on "plus sign"
Double-click on the row for the new fluid, rename it to Methanol and enter 100 moles for
Methanol in the Components grid and click Close.
Still on the Fluid manager, click on the Fluid mapping tab and map the Methanol fluid to the Inj
(Injector) by selecting it from the dropdown list.
Exit the Fluid manager.
Double-click on the Inj (Injector). Specify a fluid injector temperature of 68°F and any value for the
liquid flowrate of Methanol (this variable will be sensitized upon later). Exit the editor.
Click the Subsea manifold and launch the System Analysis task.
Set Outlet Pressure as the Calculated Variable and specify a Liquid flowrate of 8,000 STB/d.
For the X-axis variable, change the sensitivity object to Inj (Injector) and the sensitivity variable to
Liquid flowrate by selecting them from the dropdown lists. Click on Range and enter a methanol
injection rate range from 0 to 500 STB/d in increments of 50 STB/d. Remove all other sensitivity
variables either by deleting their values or unchecking the Active boxes for them, as below.
22
aystem analysts
Sutnea Manifold - System analysis
Name:
• Description:
System analysts
Engine console
System results
Profile results
GENERAL
Brandi tart
Subsea Mamfold
CALCULATED VARIABLE
inlet pressure
Branch end:
Sk
• Oitlet pressure
Sensitivity configuraton Change m step with Vanable 1
Liquid flowrate
•
1500
psia
BOCO
STB/d
Custom
o
□
PIPESIM
Reset boundary conditions
0 1 yoose
12. Click Run.
13. Double-click on the System results plot and change the Y-axis variable to Maximum Hydrate sub¬
cooling temperature difference. This is the maximum value of the Hydrate sub-cooling
temperature difference throughout the system for each of the cases run.
14. From the plot, determine the required Methanol injection rate to maintain the flowing fluid
temperature above the hydrate formation temperature, at every point in the system (i.e.
Maximum Hydrate sub-cooling temperature difference < 0). You may refine the range of the
methanol injection rate to more accurately determine the minimum amount required.
23
1
□
BE System analysis
X
Subsea Manifold - System analysis
Name:
Description:
System analysis
Show grid
Engine console
•
System results
Profile results
Show plot
AXES SERIES
Select Bottom X-axis: Inj-U'quidRowRate
*
STB/d
J
Select Left Y-axis:
Maximum hydrate sub-cool...
*
degF
E
Select Right Y-axis:
None
o o
Run
□
Stop
PIPESIM
©
J CkKt
Screen for severe riser slugging
In this task, you will screen for severe riser slugging.
1. Continue with the model from the previous exercise. Deactivate the methanol injector by rightclicking on it and selecting Deactivate. Re-enter the tieback and riser insulation thickness
determined from the previous exercise that is required to prevent hydrate formation in the system
(1").
2. Click the Subsea Manifold and select the System analysis task from the Home tab
3. Set Outlet Pressure as the Calculated Variable, and leave the default Inlet pressure and Liquid
flowrate values.
4. For the X-axis, select System data as the sensitivity object and Liquid flowrate as the sensitivity
variable. Enter the following flow rates: 8,000, 14,000 and 16,000 STB/d.
5. Click Run.
6. Double-click on the System results plot and change the Y-axis variable to display the variable;
Severe Slugging Indicator - Pots. This represents the minimum value of the Severe Slugging
Indicator number along the subsea tieback, at the base of the riser.
24
BE
System analysis
Subsea Manifold • System analysis
Name:
Description-
Engine console
System analysis
Show gno
•
System results
Profile results
Show plot
AXES SERIES
*
J
Select Bottom X-axis System Data-LquidciowRate
-
Select Left Y-axis:
*
5] Select Right Y-axis:
Severe siuggug indicator
STB/d
None
System analysis : Subsaa Manifold • System analysis
O O
Run
□
Stop
Q
PIPESIM
*/
dost
Size a slug catcher
In this task, you will screen for severe slugging and determine the required size (volume) of the slug
catcher based on the largest volume of the following criteria, incorporating a safety factor of 20%.
You must design the slug catcher taking into account the following criteria:
•
•
•
Hydrodynamic slugging: This typically generates the largest slugs of all the scenarios. The
design is based on the statistical l/1000th population slug size, determined using the SSB or
Norris Correlations.
Pigging volume
Transient effects, such as the requirement to handle the liquid slug generated when the
production flow is ramped up from 8,000 to 16,000 STB/D, such as a ramp-up surge
Note: The slug-catcher will be sized to address the above scenarios only, and not severe riser slugging.
We will assume that the severe riser slugging scenario can be mitigated with topsides choking or riser-
based gas lift.
1. From the Home tab, go to Simulation settings > Output variables. The Flow Assurance report
template is selected. Click on the Clone button to make a copy, so you can customize it. Type in
any name you want for the cloned report.
2. Click the Profile tab to see all the selected profile variables. To see the complete list of profile
variables, click the Selected tab to deactivate the selection. Add the following profile variables of
25
I
3.
4.
5.
6.
interest that are not included in the Flow Assurance template by default, by checking the box next
to each of them (Enter the first few letters of each variable in the Type to filter box, to filter the
list):
• Sphere-generated liquid volume from section (profile variable)
• Total sphere-generated liquid volume so far (profile variable)
• Cumulative liquid holdup (profile and system variables)
Click the System tab and add the system variables below, if missing.
• Sphere generated liquid volume (system variable)
• 1in 1000 slug volume (profile and system variables)
• Exit the dialog box and save your workspace.
Launch the P/T profile task and set it up with Outlet pressure as the Calculated variable. Leave the
default values for the boundary conditions. Under Sensitivity Data, select System Data as the
sensitivity object and Liquid flowrate as the sensitivity variable and enter the three liquid flowrates
that have been used in the previous exercises ( 8,000, 14,000 and 16,000 stb/d).
Click Run.
On the Profile results tab, select Show grid, then click Select Columns and add the following three
variables to the grid.
• Total/Cumulative liquid-holdup
•
1in 1000 slug volume
• Total sphere-generated liquid volume so far
7. Click Close to exit the Select columns dialog and scroll to the end of the Profile results grid to see
these variables. Change the units for all 3 variables to bbl.
8. For each sensitivity rate, extract the maximum 1/1000 Slug Volume and the Total SGLV so far
(Sphere Generated Liquid Volume) at the system outlet and record them.
26
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10 UQ*16000 lacx/Oaf OBowi.ne
1ijUQ. 16000 ODI/dJy OBowls*
Bowfcne
12 UQ.16000 i»t>i/dj» O_
1
*
sw
*.«*•«*
1S00
1417429
1455523
14JJ065
1410441
11376*9
1164665
1141471
1114067
176
1721546
•
IW
2*54146
24 47668
2*0154
1644115
164.7557
1611254
157 567J
15*0648
1506097
2*61066
2*40*12
2494151
2517591
251906*
2561454
2197179
2149C11
254025*
07X25624. H*.mr*n» Undefned
07125*964 *Wffini*n« Undef-ned
071512764- HttnMien* Undef-ned
071774465. Htownnent Undef-ned
25*9908
2159004
0 7*061HI. Wmnw
Q7*J78St4- Wemw*
21*7911
211549
2121975
2106t*1
074709625
147.194
254587
2612541
14060*3
-1600
1244317
1171*14
264216
2672991
-1600
1221455
1142228
Bowls*
-1600
11970*2
1111207
Bowls*
Bowline
-1600
1171471
121057
-1600
-1600
-1600
•1600
1146J21
1120 JS4
1250192
1220461
1091913
1191165
Rowline
Bowline
Rowtne
106701
2706712
27*3756
2741997
2426141
247245
292*651
9092042
109.0421
127.1046
1451336
161)201
1815124
DU
0
17.16983
7*25515
1112233
1430696
18*7647
2212911
2576*9
2918115
1293116
365S66
M6enn.t*n»
Undef-ned
m*rm.i»r*
Undef-ned
1524659
199786*
2181479
416299
22515*1
221159
2210971
0771164)1
Wemtlrt
Undefined
159261
1615501
07744t)47_
Wermnem
Undefined
168 7739
2165104
254 7016
076464642- lUe-ntlrt
Undefined
471231
50546S6
5401349
5741684
6077796
640.9905
6717461
70608*1
7060978
2148071
2162762
294214}
21 1*921
111*151
30*2911
110611
2107124
2074611
Rue-
-1600
1011464
110611
11096
1109717
Rue*
Rrter
-900
0
9566686
1066411
1024595
1270182
1**3626
11147)5
25 UQ. 16000 -.bai/dey 0-
Rise*
60
1025919
1*6268
1112US
9010239
9990524
1472938
7274071
'
076791001. Mtimiitem Undefined
1011464
-
1292631
115091
141 1725
1*22501
1641182
54 530*9
07547144)
1019511
1162464
075445605. wentvnem maefned
120 6353
001152214
076)12905.
•1600
•1600
UQ.16000 rooVday O.
UQ> 16000 tboi/<U)fO.
Undefned
Undef-ned
Undef-ned
Undefined
5142679
8822447
1014468
1118699
Jot SGIV » tot H.
• DW
2249579
Bowline
X
Wer-n.nent
Q 75054914. Htennnent
Undefined
2271201
21 UQ.16000«»i/d»yO_
22 IIQ.16030 taot/ddy O Rue21JUQ.16000 iOW/ddyO2* UQ- 16000 tt>W/d*»0_
if
wwnuaenj
■«-
O-WPette-n 1/1000sK*j
Q 7282*211.
1414598
Bowhne
G-lPettern
%
2*04102
1294.425
1270522
■
•
1401304
t16974)
079114)98
Wrutlml Undefined
079824509 H*rm«*n« Undef-ned
040605244 . MimfflW Undefined
041422148- hSftmlMnl Undef-ned
0009755.
Unlefned
042111102 Slug
Undefined
04*408277. Slug
Undef-ned
0466406*2. Skjg
Undef-ned
04645ftH0. Slug
Undefned
1719255
2729241
179.1799
291294
3014405
1285935
147.1074
1846071
1902309
1960905
2022216
1654915
2022298
3654979
212961S
2255*93
17210*8
179.105
1795946
2265704
*010664
7169042
7274S29
7282112
10. Assuming the design is based on a ramp-up volume from 8;000 to 16,000 stb/d, the ramp-up
volume would be the difference in total liquid holdup in the system between the 8,000 stb/d and
16,000 stb/d cases. Extract the total liquid holdup at 16,000 stb/d and at 8,000 stb/d and subtract
the 2 values.
Note: The surge associated with ramp-up occurs over a much longer time period than the other
cases. When sizing a slug catcher for a ramp-up scenario, consideration should be given to the
volume that will be discharged from the vessel during the ramp-up. For more information on how to
calculate the ramp-up duration, see Cunliffe's method for ramp up surge.
11. Determine the highest volume of the 3 scenarios and apply a safety factor of 20% to get the design
volume for the slug catcher. Compare it with the answers below.
Parameter
Slug Catcher Sizing
1/1000 slug volume (bbl)
Sphere generated liquid volume (bbl)
Total liquid volume (bbl)
Ramp-up volume (bbl)
Design volume for slug catcher (bbl)
Values
8000 stb/d
14000 stb/d
164
185
378
375
875
765
875 - 728 = 147 bbl
379 * 1.2 = 454.8 bbl
16000 stb/d
226
379
728
28
Looped gas gathering network
In this tutorial, you will learn how to build a gathering network and perform a network
simulation to evaluate the deliverability of the complete production system. It is necessary to
model the network as a complete system to account for the interaction of wells producing into
a common gathering system. The wellhead pressure, and by extension the deliverability of
any particular well is influenced by the backpressure imposed by the production system.
Modeling the network as a whole, allows the engineer to determine the effects of such
changes as adding new wells, adding compression, looping flowlines and changing the
separator pressure.
Model a pipeline network
In this tutorial, your goal is to establish the deliverability of a production network. The
network consists of three gas wells producing into a looped gathering system, which delivers
the commingled streams to a single delivery point.
1. Launch PIPESIM and create a new, network centric workspace.
2. From the Insert tab, add the following equipment:
o 3 wells (Use the Simple Vertical template for all wells).
o 4 junctions
o 13-phase separator
o 1 compressor
o 1 heat exchange
o 3 sinks
3. Rename and arrange them exactly as indicated below.
Cmp
HX
GasSales
Oil Storage
4. Connect the inserted objects using flowlines and connectors such that the network diagram
exactly matches the figure below. (Rename all the flowiines exactly as indicated below).
29
aj
5. Create 2 new compositional fluids for the 3 wells based on the compositions below. Set the PVT
package to Multiflash and select the 3-parameter Peng-Robinson option as the Equation of State.
Leave all other model settings to their default values, but name the fluids as indicated below.
Moles
Fluid_A (Well_l & Well_2) Fluid_B (Well 3)
10
Water
6
Methane
67.5
71
Ethane
5
6
Propane
2.5
3
Isobutane
1
1
Butane
1
1
Isopentane
1
1
Pentane
0.5
0.5
0.5
Hexane
0.5
Carbon Dioxide 2.5
4
C7+
8.5
6
Molecular Weight
Name
Specific Gravity
C7+
0.683
115
Component
6. After creating the 2 fluids, map
manager, as below.
WellJL and Well_2 to Fluid_A and Well_3 to Fluid_B in the Fluid
Fluid manager
Fluids
Fluid mapping
Current selection
Well
1
1 Well 1
2
3
| Well 2
j Well 3
Component/model settings
T Wellstream outlet
Source
Fluid
Completion
Completion
Completion
Fluid_A
Fluid_A
Fluid.B
Override... Gas ratio type
•i
•
•'
□
□
□
GOR
GOR
GOR
Gas ratio
Gas ratio unit
Water ratio type Water ratio
Water ratio unit
7777.255
7777.255
12316.72
SCF/STB
SCF/STB
SCF/STB
Watercut
Watercut
Watercut
%
%
%
9.879613
9.879613
7.702981
7. Save your workspace.
8. In a previous step, you created all 3 wells using the Simple Vertical template. You will now edit the
default template values for each well and change them to the values specified below.
30
Properties
Unit
Well_l
Well_2
Well_3
Well type
-
Vertical
Vertical
Vertical
Casing (Bottom MD)
ft
Casing ID
inch
inch
4700
6.765
0.43
4600
6.765
0.43
4800
6.765
0.43
4450
4350
4550
2.441
0.217
0.001
4200
2.441
0.217
0.001
4100
Casing Data
Casing wall thickness
Tubing Data
Tubing (Bottom MD)
Tubing ID
Tubing wall thickness
Roughness (casing/tubing)
Packer depth (MD)
Wellhead ambient temperature
Heat transfer coefficient
Completion Data
ft
inch
inch
inch
ft
deg F
60
BTU/(h.degF.ft2) 2
60
2
2.441
0.217
0.001
4300
60
2
Fluid entry
-
Single point
Completion depth (MD)
ft
4500
IPR model
Reservoir pressure
psia
Single point
4400
Back pressure
2900
130
4E-06
Single point
4600
Back pressure
3100
140
5E-06
Reservoir temperature
Constant C
deg F
mmscf/d/psi2n
Back pressui
2900
130
4E-06
The three (3) wells display as below.
Well 1
General
*
SURFACE EQUI
WfL-1
Tubulars
Mode:
Dimension option:
Name
Tubing flow from
Completion
Deviation survey
Bottom MD
ft
1
1 Casmg 1
2~ J Tub ng
Downhole equipment
Artificial lift
Heat transfer
Completions
Surface equipment
« Simple
Detailed
OD
• Wail thickness
ID
• in
Wall thickness
• in
4700
6.765
0.43
4450
2.441
0217
Roughness
jin
0.001
0.001
m
_
-
Equipment
Tubing
Completion
Casing 1
31
*
General
~
Deviation survey
Tubulars
Artificial lift
Heattramfe
Completions
Surface equ pment
COMPLETIONS
Geometry pro
Name
f
Downhole equipment
[Completion
•
am ■ n—
L+J
Reservoir
fluid ent7
Verbcai
Single pent
Top MD
Middle MD
ft
ft
J
Bonom MD
Type
IPR model
Active
-ft
4500
Perforation
Bade press...
■／
Fluid model
Reservoir pressure:
2900
psia
Reservoir temperature: 130
degf
IPR basis:
Constant C
Gas
4E-06
mrmcf/d/psi'2n
Slope rr
1
Use test data:
0
5
is
10
20
2S
30
Q (mmtcf/d)
4700 ft
Well 2
General
SURFACE EQUI
Wf12
Tubulars
A
L2
{Tubing
Mode:
Dimension option:
Name
flow from
Completion
_
Deviation survey
• Simple
OD
ft
1
I Casing t
2 j Tubing
•
4600
4350
Oownhoie equipment
Artificial lift
Heat transfe-
Compietons
Surface equipment
Detailed
Wall tftickness
Bottom MD
10
• [in
6.765
2.441
*
iWUyJHMMi
Wall thickness
043
0217
Rougnness
in
0001
0001
m
-
Scupment
Tubing
Completion
Casmg 1
4600 ft
32
»
:13.«
M.
OIL
*
SURFACE EQUI
r'
WR-2
COMPLETIONS
12
Name
Tubing Mow Hem
Completion
i
1 [Completion
Vertcal
t+J
Reservoir
• [Single point
Middle MD
Top MD
Geometry pro_ Fluid entry
1
• ft
/*
*|
Bottom MD
Type
Active
tPR model
I'S
Bac* press
• ft
|4400
:
Perforation
Fluid model
Reservoir pressure:
2900
psia
Reservoir temperature liO
IPR basis-
degF
Gas
Constant C
4E-06
Slope x
1
mmscf/d/psiA2n
Use test data:
Equipment
_,
HQQjft
Tubing
±3SQJL
44QQJ8
Completion
_
Casing 1
4600 ft
Well 3
General
*ÿ
SURFACE EQUI
TuOua'S
Mode
WFl-3
Dimension ootica
a
Name
Tubing flow from
Devaton survey
•
Simple
OO
1_j Casing 1
"2 |TuO'ng
43CC
4550
Artificial lift
Heat transfer
Completions
Surface equipment
• Waii tr*cimess
Bottom MD
ft
Completion
Downhole equipment
Deta.ea
ID
• m
6.765
144
*
Waii Mcknes
Roughness
m
m
0.001
0X01
043
0.217
CD
Equipment
Tufang
I
Completion
1
1
4600 ft
33
•|
General
33.ft
~
Tubular*
Deviation survey
Downhole equipment
Artificial lift
Heat transfer
Completions
Surface equipment
COMPLETIONS
Reservoir
Fluid model
Reservoir pressure
3100
psia
Reservoir temperature 140
degf
IPR basis:
Gas
ConstantC
5E-06
Slope it
1
mmscf/d/psi*2n
Use test data:
9. Click the Flowline manager on the Home tab and specify the flowline details as below. (Double¬
click the Name column to sort in alphabetical order to make it easier to enter the data).
*3
□
Flowline manager
Name
» Hor. distance
ft
1
Fl-1
FL-2
WFl-2
11 WFl-3
30C00
30000
30000
30000
263
128
10000
467
24
24
24
'2
243
2
3
4
FL-3
Fl-4
5
FL-5
6
7
8
GL-1
Gl-2
OL-1
WFL-1
9
10
WL-1
Eiev. diff.
ft
0
0
0
0
Undulation
•1
ID
• jin
0
0
6.065
6.065
0
Wall thickness
rn
in
Amb. Temp.
*
deg?
028
0.0018
0.0018
60
60
6.065
028
0.0018
60
0
0
0
0
0
6.065
10.02
7.981
7.981
6.065
028
0.0013
0.0018
0
0
0
0
4.026
0.0018
0.0018
0.0018
0.0018
60
60
60
60
60
60
0
0
4.026
4.026
0.0018
0.0018
60
60
0
0
6.065
0.0018
60
0
0
0
0
0.28
Roughness
0.365
0322
0.322
028
0237
0237
0237
028
Detailed Override global
•
□
□
10. Exit the Flowline manager.
You will notice that all the flowlines are valid.
11. Double-click the Separator (3PS) and select Gas as the Production stream. Leave the default value
of 100% for both the Gas/Oil and Water/Oil efficiencies.
12. Without exiting the separator dialog box, click the Compressor and enter a Pressure differential
of 400 psia and an Efficiency of 70%.
13. Without exiting the Compressor dialog box, select the Heat Exchanger and enter a Pressure
differential of 15 psia and Discharge temperature of 120 degF. Exit the dialog box and save the
workspace.
14. Go to Home » Simulation settings » Flow correlations and choose Beggs & Brill Revised as the
global vertical and horizontal multiphase flow correlations.
15. From the Home tab, launch the Network Simulation task.
16. Configure the boundary conditions for the simulation task, as shown below.
34
X
J-*
Network v mutation
Name
Network simulation
Description;
Network simulation
Boundary conditions
Rate constraints
Type filter
All
Location of well boundary conditions:
•
• Required P.Q specifications:
6
6
Supplied P.Q specifications:
Surface
Reservoir
Override phase ratios:
Name
Type
Completion
Active
Pressure (P)
1
Well 1
Well 2
Well 3
4 ; Gas.Sales
S Oil.Storage
6 WaterJ'eatment
2
3
V
Completion
Completion
Completion
Well
Well
Well
2
j
V
V
Sink
Sink
Sink
ss/ss/s/s
«/
Flowrate (Q)
Flowrate type
Flowrate unit
•
psia
2900
2900
3100
aoo
250
60
Temperature
Zone
PQ Table
clu*d
degF
Liquid
Liquid
ST8/d
STB/d
130
130
Liquid
Liquid
STB/d
140
*
Liquid
Liquid
*
r;77777771"
//s.
;s// /.
FluidÿA
Fluid.B
STB/d
////////V
STB/d
'/////',
fl/jLdSJL/zj.
STB/d
FkrdJL
77777/77?
'//y///yy/K
17. Click Run to launch the simulation.
18. View the Profile results.
3
iWwn HOMKW
Htmt
vrtMCK5n
Oficpcoa
Uetwoit imt/Mon
t'vjTc ny«x
So<JeyS'*no -«UTs
Snoujwi
*or.* >tM!i
• Smskoi
Bran
1
2
1
UJ*
4
i4.nr:
s
v
CuStO'f
M J*
AXES SERIES
W*« 1
6
7
IRS CS*COnO«ni’.<X I
a
njl
4
W4l>“
10
IPS ,S«cyvU'>l.Wl
Gli.S**'.
12 Wf.l 1
1
11
11 ips.a-i
14 Wfi 2
o
Ruri
>
V
iij4
«
JRS cs«on«*r,j.a-i J
I4.VS
V -*-»•«!
ms 'AOTUY.X'I
-
v-ÿjes.a-i
CN.itt.*}*
y
u jJ
/
i
ut
©
Restart
19. Plot the profile results for the flow path from Well_3 to the Gas_Sales sink as annotated below,
by selecting the highlighted branches. Observe the 400 psia pressure boost provided by the
Compressor.
35
x
20. Review the Node/Branch results and determine the network deliverability. Compare your results
with the answers below.
Netwcv* smuUtion
Name
Network simulation
Description:
Network simulation
Display moce
•
Type filter
All
Engine console
Node
III Select columns.
Sode/Brand 'esuiK
Profile results
Brand
O Expand ail
Name
Type
Brand
Pressure lout) Temperatur-. ST pu d rate ST 0>i rate
pw
1
Completion
2
3
Completion
Completion
Cmp
5 HX
11
.
4
*
7
Completion
Completion
Completion
79.15355
Junction
339.0111
463.259
300
79.13386
61.72706
Junction
Gas.Sales
Sink
Well 2
16 Well 3
15
151.615
8269915
J4
Weil 1
1213471
8142062
9
14
133.1726
1211555
351.3*49
346.3949
360.7196
3
Oil.Stwage
12 Water .Treatment
13 3PS
2521.007
2253335
2272305
Compressor
Heat exchange'
Junction
Awction
J2
J3
10
11
Welt 3
Wen 2
WHI 1
• deg*
Sink
Sink
Three phase separator
Well
Weil
Weil
250
60
4613862
271.635
251.711
5830612
58*4507
61.65627
STB/d
1431444
1888.986
1852 344
0
0
1852344
2898032
2274.907
5171125
0
5618095
575.7779
0
362.6809
83.48752
1852.344
829.121
82.74431
8230426
1888.936
841.7186
1431444
•
STB/d
1321.18
1702.361
1669.34
0
0
1669.34
2611.718
2081328
4691231
0
5618095
0
0
1669.34
1701361
1321.18
ST Water rate ST Gas rate
•
STB/d
1101638
1866245
1830044
0
•
mrreef/d
1627261
112397
1298288
3843795
3843795
1298238
STGOR
*
SCF/ST8
1231672
77772SS
7777255
STWCUT
•]%
7.702981
9*79613
9*79613
0
0
9*79613
9*79613
8509308
0
1830044
286.3144
20312
1915788
479*937
0
4149478
3843795
9CS4.482
0
1374471
4216471
575.7779
0
1830044
4700029E07
3845381
1193288
7777255
1866245
1102638
112397
7777255
9276669
0
0
100
0
9*79613
9*79613
1627261
1231672
7.702981
21183
7777255
7777255
106581
a Gas rate (_ n. WCJT
• mmef/d
%
4.68259
OQS424S62 5334556
005270976 531686
07013705
0
09032524
0
7.419537
01714323
02778148
7.451164
03013704
6413761
1.107933
7.6383S3
09255818
0
004033428 2714809E06
1043313E-08 100
1.111777
19.61053
01709814
7.416296
01828455
7.47891
02237806
3934952
0.06597003
21. Determine the drop in Gas production in the event of a compressor shutdown. This scenario
assumes that there is a bypass line around the compressor that allows gas production to be
maintained if the compressor goes down. Simulate this scenario by right-clicking on the
Compressor and selecting Deactivate.
22. Rerun the Network Simulation task and compare your results with the answer below.
36
Network simulation
Name:
Network simulation
Description:
Network simulation
Engine console
Display mode: • Node
Type filter
Name
1
2
3
Complebon
Completion
4
hX
J1
S
Completion
J2
i3
' 14
Gas.Sales
10 Ol.Storage
11
Water.Treatment
3PS
13 Weil 1
Well 2
15 Weil 3
14
Profile results
All
121 Select columns-
6
7
8
9
Node/Branch results
Branch
© Expand all
Type
Completion
Complebon
Complebon
Heat exchanger
Juncton
Junction
Juncton
Junction
Sink
Sink
Sink
Three phase separator
Well
Well
Well
Branch
Well 3
Well 1
Weil 2
Pressure (out)
•
psia
2551.96
2317617
2304.027
8326353
1078.909
105S737
10648*7
8438734
800
250
60
348.2615
1080266
1057184
1066.756
Temperatur._ ST liquid rate ST Oil rate
•
ST Water rate ST Gas rate
ST GOP.
•
mmscf/d
SCF/STB
15.43749
1231672
1215461
7777255
deg?
STB/d
133.601
136238
1257.436
104.9439
123.9563
123.7729
193.9317
3938446
1734.17
156284
1713292
1770014
0
1595.143
1240584
34.50326
7777255
0
156284
1748705
0
1713292
2471.406
2709325
1215461
1922076
2124376
4866896
0
5147116
1944.165
4415.751
0
5147.116
1802116
451 1445
0
0
7777255
7777255
1071257
544 6493
0
0
5446493
0
1734.17
0
156284
1770.014
136238
1595143
1257.436
1748705
84.51321
85.49943
7400982
1792828
63.31813
6288769
7296734
89.42672
89.1347
90.00128
1734.17
2742339
STB/d
ST8/d
1713292
104.9439
2082701
40.04755
906925
3480326
3.978239
7729065
8.002265E-07
34.69408
7777255
1215461
7777255
1240584
15.48749
1231672
•
STWCUT
%
7.702981
9979613
997%13
0
997%13
9879613
8483034
926%56
0
0
*
Fl Gas rate <_ FI WCUT
%
mmcf/d
0.06193305 4881314
0.04793544 5.46321
004935407 5478955
0.7158831
0
0.1227803
707189
7071364
0.1959293
02139386
03225192
0.7243795
9879613
0.1219235
3313305S-08
03231303
0.1225972
997%13
0.1286129
7.702981
0.1625897
100
0
6067753
6870552
0
2849167E-C5
100
1279276
7.069636
7113732
5.64363
Screen the network for erosion issues
In this task, you will screen the network for branches that exceed the erosion velocity limit.
Do the following:
1. Re-activate the compressor by right clicking it and selecting Activate.
2. Go to Home > Simulation settings > Erosion/Corrosion and confirm that the API 14e erosion model
is selected and the default Erosional velocity constant (C value) of 100 is being used.
3. Run the Network Simulation task.
4. Go to the Profile results tab, select Show plot and change the Y-axis variable to display Erosion
velocity ratio. The erosional velocity ratio (EVR) is calculated as below.
Fluid velocity
:
EVR
= Erosion velocity ccilcidcited by the Erosion model
If EVR > 1, there is an erosion risk.
5.
Display the EVR plot for all branches.
You should get a plot similar to the one displayed below.
37
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6. Identify the branches where the EVR exceeds one and compare them to the answers below.
Why do these specific branches have the highest EVR? (These are the well branches. They have
the highest flowing pressures and temperatures, hence highest fluid velocities).
7. Determine possible solutions to get rid of the erosion issues and implement them in the network.
38
*
