cfd applications for deepwater platforms at technip -...
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CFD Applications for Deepwater Platforms at Technip
Speaker: Allan Magee, PhDR&D Manager Offshore Product Line & Technology, Technip Malaysia Technip Chaired Professor in Offshore Technology, UTP Dept of Civil Engineering
CD-Adapco STAR South East Asian ConferenceCD Adapco STAR South East Asian Conference 5-6 Nov 2012
Table of Contents
Technip Introduction p
R&D on Floating Platforms
Early CFD ApplicationsEarly CFD Applications
Design of Floating Platforms for Southeast Asia
Riser VIV Suppression
Ringing of Offshore Platform
Future Work
Conclusions
2
Technip TodayWith engineering, technologies and project management, on land and at sea, we safely and
successfully deliver the best solutions for our clients in the energy business
Worldwide presence with 32,000 people in 48 countries
Industrial assets on all continents a fleet of 34 vessels (of which 5 under construction)Industrial assets on all continents, a fleet of 34 vessels (of which 5 under construction)
2011 revenue: €6.8 billion
Energy is at the core of TechnipTechnip Slide Library3
Three Business Segments, One Technip
Engineering and fabrication ofDesign manufacture and supply of Gas treatment and liquefaction
Subsea Offshore OnshoreEngineering and fabrication of fixed platforms for shallow waters (TPG 500, Unideck®)
Engineering and fabrication of floating platforms for deep waters (Spar semi-submersible
Design, manufacture and supply of deepwater flexible and rigid pipelines, umbilicals and riser systems
Subsea construction, pipeline installation services and Heavy Lift
Gas treatment and liquefaction (LNG), Gas-to-Liquids (GTL)
Oil refining (refining, hydrogen and sulphur units)
Onshore pipelines(Spar, semi-submersible platforms, FPSO)
Leadership in floatover technology
Floating Liquefied Natural Gas (FLNG)
installation services and Heavy Lift
Six state-of-the-art flexible pipe and / or umbilical manufacturing plants
Five spoolbases for reeled pipeline bl ll f l i i
Petrochemicals (ethylene, aromatics, olefins, polymers, fertilizers)
Process technologies (proprietary or through alliances)
Construction yardassembly as well as four logistic bases
A constantly evolving fleet strategically deployed in the world's major offshore markets
or through alliances)
Biofuel and renewable energies (including offshore wind)
Non-oil activities (principally in life sciences, metals & mining,
t ti )
Technip
Slide Librar
y
4
construction)
The best solutions across the value chain
Technip in Asia Pacific
A long-standing presence in Malaysia since 1982
Nearly 4 400 peopleNearly 4,400 people
Assets in the RegionAsiaflex Products: flexible pipe & umbilical manufacturing plant – 1st and only one in Asia Bangkok
Shanghai
Logistics base in BatamFuture new vessel, Deep Orient (under construction): flexible & umbilical pipelaying vesselFabrication yard: TMB
Kuala Lumpur Tanjung Langsat
JakartaSingapore Balikpapan
Batam
Hull design: TMH
Main expertiseDeepwater subsea developmentsOffshore platform & field development
Perth
New Plymouth
Offshore platform & field developmentOnshore facilities for oil refining, gas processing/liquefaction (LNG), petrochemicals and non-oil industries
Regional Headquarters
Operating centers
Flexible pipe/umbilical plant
Logistic BaseConstruction Yard
5 Technip Slide Library
Table of Contents
Technip Introduction p
R&D on Floating Platforms
Early CFD ApplicationsEarly CFD Applications
Design of Floating Platforms for Southeast Asia
Riser VIV Suppression
Ringing of Offshore Platform
Future Work
Conclusions
6
Who We AreOffshore Product Line & TechnologyOPL&T at Technip MalaysiaOPL&T at Technip Malaysia
Part of a broad Technip R&D effort to complement the Centers inHouston and ParisBranch in Kuala Lumpur since 2008/2009Branch in Kuala Lumpur since 2008/2009Purpose: Bring R&D closer to the regionMain Focus areas: Regional floating platform technologies
Floatover InstallationsModel testing at local facilitiesNumerical wave tank with Computational Fluid Dynamics
VIM of multi-column floaters (SEMI, TLP)( , )Fluid-Structure Interaction (FSI)
Links to other centers forTechnology gapsCoordinationCoordinationTraining
Why Computational Fluid Dynamics?Provide design assurance using the most accurate tool for first of a kind offshore structuresBest available estimatesof hydrodynamic loadsCorrelation with other modelsExtrapolation to fullscale Re. No.Quicker than a model testProvides more information
Complements/completes test dataComplements/completes test data
Able to remove simplifying assumptions inherent in other theories Yet retain these results as special cases
Unsteady effects included (not constant added mass/drag coefficients)y ( g )Large volume structure (diffraction included - not slender members)Separated flow for bluff bodies (not potential flow) Non-linear free surface (not linear theory)
Run-up/ Air gapRun up/ Air gapSteep and breaking waves
Pressure mapping onto dynamic structural model (SACS mode shapes)Load mapping onto ANSYS modes (ongoing w/ TP Houston)T t t f h d t ti t ti d d i l d APITreatment of hydrostatic, static wave and dynamic loads per API
Get structures+ Hydro guys to talk the same language
Floating Production Platform Overview► A Floating Production Platform is a complex,
integrated system :
• Topsides– Process Plant
– Drilling/Work over Rig
– Living Quarter
– Marine Systems– Marine Systems
– Safety Equipment
• Hull– Buoyancy to carry Topside, Moorings and Risers
Heave Platesy y y p , g
– Stability to avoid capsizing
– Motions to perform Drilling and Processing
– Support and Protect the Risers
Plates
• Moorings– Station Keeping
• Risers
9
– Controlled transport of Hydrocarbons from Reservoir to Process Plant (import) then to Pipeline or Tanker (export)
Table of Contents
Technip Introduction Sea surface
p
R&D on Floating Platforms
Early CFD ApplicationsSeachest
CenterwellEarly CFD Applications
Design of Floating Platforms for Southeast Asia
Deck 3Plate
Centerwellsea surface
for Southeast Asia
Riser VIV Suppression
Ri i f Off h Pl tf
Heaveplate Hull
Ringing of Offshore Platform
Future Work
10
Conclusions
CFD Application: Heave Plates with skirtsI ti ffi i t f i ki t fi ti
Flat Plate
Inertia coefficients for various skirt configurations
0.8
0.9
1
a
0.5
0.6
0.7
0.0 0.2 0.4 0.6 0.8 1.0 1.2
Ca
Skirt Away
c/a
b/a = 0.23 b/a = 0.13 no skirt
Drag coefficients for various skirt configurations
7
8
9
10C
d
Skirt at Edge 4
5
6
0.0 0.2 0.4 0.6 0.8 1.0 1.2
c/a
11
/
b/a = 0.23 b/a = 0.13 no skirt
Design of Floating Platforms for Southeast AsiaSoutheast Asia
12
Unsteady Flow around a TLP Hull using Star CCM+
Background on Vortex-Induced Vibrations (VIV)
Cylinder in a current develops unsteady, alternating vortex pattern in wakeThe alternating vortices give rise to lift forces, perpendicular to currentIf vortex shedding period, Ts, approaches the natural vibration period, T, g p pp pof lateral motion, lock-in occursAmplitude of the motion A, is normalized by cylinder diameter DFor VIV due to currents at speed U, the most important parameter is the p , p preduced velocity
For large mass ratios (flagpole in the wind)D
UTUr =
g ( gp )the cylinder “locks-out” for 5<Ur>7
A/D
K V t St t b hi d fi d li d (Wiki di )
13Model Testing of Floating Platforms at UTM
Karman Vortex Street behind a fixed cylinder (Wikipedia)Animation of the phenomenon. Courtesy, Cesareo de La Rosa Siqueira.
From Flow Induced Vibrations, R.D Blevins,1990Ur
Solver Benchmarking: Model Scale Spar VIMAtluri et al, OMAE 2006Atluri et al, OMAE 2006
150 deg Heading
0 50
0.35
0.40
0.45
0.50ExperimentSimplif ied (AS)Simplif ied Appendages (AS)Full (AS)Simplif ied (AN)Full (AN)
0.15
0.20
0.25
0.30R
MS
A/D
( )
0.00
0.05
0.10
4 5 6 7 8 9 10
Reduced Velocity (Vrn)
14
ObjectiveExtend existing CFD capabilities for Spar VIM prediction to multi-
l l tf h TLP d SEMIcolumn platforms such as TLP and SEMI
15
TLP Model Towed to Simulate CurrentsMeasure Vortex-Induced Motions
16
Vortex-Induced Motions (VIM) of a TLP in Steady Current using Star CCM+
Calculations Using Star CCM+
Physics model: Incompressible Navier-Stokes(Air/water Volume of Fluid with free surface)Turbulence models: RANS and Spalart-Almaras / Detached Eddy Simulation (SA/DES)(SA/DES)Eulerian, body-fixed grid6-DOF coupled rigid body motions (DFBI)Domain size: 4m x 4m x 6m (Width x Depth x Length)Domain size: 4m x 4m x 6m (Width x Depth x Length)Mesh: Approx. 500,000 hexahedral cells (trimmer mesh)Max cell size: 0.5mMin cell size: 0.0025mTarget cell size on TLP: 0.0125mNo. of prism boundary layers: 4Total thickness of prism layer: 0.015mp yTime step: 0.01s, Implicit, 2nd order accuracy5 sub-iterations per timestepCalculations performed at model scale (1:70)
Mesh
Figure 10. Horizontal and vertical mesh slicesshowing the distribution of elements near the TLP model.
Calculated Sway Motions Using Star CCM+
0 10.20.30.4
A/D
)
0 511.52
eg)
0 1
0.2
0.3
0.4
D)
0 5
1
1.5
2
g)
-0.3-0.2-0.10.00.1
Sway
(A
-1.5-1-0.500.5
Yaw
(de
-0.3
-0.2
-0.10
0.1
Sway
(A/D
-1.5
-1
-0.50
0.5
Yaw
(deg
-0.40 500 1000 1500 2000 2500
Time(s)
-2
Sway(A/D) Yaw(deg)
-0.40 500 1000 1500 2000 2500
Time (s)
-2
Sway (A/D) Yaw (deg)
Figure 11. Sway(A/D) and Yaw(deg) vs Time(sec) from CFD analysis using RANS
Figure 12. Sway(A/D) and Yaw(deg) vsTime(sec) from CFD analysis using SA/DESTime(sec) from CFD analysis using RANS
approximation, Ur(sway)~8, Ur (yaw)~5, 45° heading, heavy draft case (2L/D=3) 4-Column TLP model from Ref [6].
Time(sec) from CFD analysis using SA/DESapproximation, Ur (sway)~8, Ur (yaw)~5, 45°heading, heavy draft case (2L/D=3) 4-Column TLP model from Ref [6].
TLP Heavy Draft 45 deg heading - Sway Nominal A/D vs Ur
TLP Heavy Draft 45 deg heading - Yaw Nominal A vs Ur
0 15
0.20
0.25
0.30
0.35
min
al A
/D
Model Test
CFD DES
CFD DES CdyStdev0.05CFD DES truncate FS 0 6
0.8
1.0
1.2
1.4
nal A
(deg
)
Model Test
CFD DES
CFD DES CdyStdev0 05
0.00
0.05
0.10
0.15
6 8 10 12
Sway Ur
Nom
CFD DES truncate FS
CFD DES SharpCorners*CFD DES Rough3e4m
CFD RANS
0.0
0.2
0.4
0.6
2 4 6 8
Yaw Ur
Nom
in Stdev0.05CFD DES SharpCornersCFD DES Rough3e-4mCFD RANS
Sway Ur
Figure 13. Nominal sway response ofCFD compared to model test resultsf R f [6]
Yaw Ur
Figure 14. Nominal response curves ofCFD compared to model test results fromRef. [6].
from Ref. [6].
Development of Novel Hull Forms:HVS Semisubmersible
Advantageous for fabrication with existing regional infrastructurePotential for application as a “Dry-Tree SEMI” in moderate SE Asia wave environment
22
Hulls Screened by CFD
Blister Case 1 Hybrid 1:B C 10 PH Blister Case 1 Hybrid 1: Vertical Plate (9m) +Short Blister (9m)
Circular StrakeBase Case – 10 m PH
Base Case – 12 m PH Square Strake Hybrid 3: 3 Vertical Plates (9m)
Blister Case 3
23
T
3 Vertical Plates (9m) +Short Blister (9m)
CFD vs Model Test
24
Title of
presentatio
n in Head
er
Reduced Velocity ( UT / D)
Flow Visualization
Vertical vortex core near columnSmall drag on pontoon
► Slanted vortex core away from column
25
Title of
presentatio
n in Head
er
Small drag on pontoon►Higher drag on pontoon
Table of Contents
Technip Introduction p
R&D on Floating Platforms
Early CFD ApplicationsEarly CFD Applications
Design of Floating Platforms for Southeast Asia
Riser VIV Suppression
Ringing of Offshore Platform
Future Work
Conclusions
26
VIV Suppression Devices
Strakes – Cd~1.8 to 2.0 Fairings – Cd~0.7
Both reduce VIVBoth reduce VIV
Fairings can significantly reduce overall drag on the TLP
Reduced payload from tendon tensions, saves $$$
But performance needs to be verified
© AIMS International
Towing Bare Riser to Simulate Currents
Riser with Weathervaning Fairing
Riser VIV Calculation Details
Approx 825,000 CellsAutoselect recommended optionsAutoselect recommended options1 Degree of Freedom, DFBIDt=0.01 sec, 5 sub iterations/ timestep2nd order time marching
17070 mm
8170
000,120~061
17.07.0Re 2
−=
sms
me
ms
5.717.0
8.17.0==
m
ssUr
30
31
Fairing Stuck at 120 degs to the flow
32
Table of Contents
Technip Introduction p
R&D on Floating Platforms
Early CFD ApplicationsEarly CFD Applications
Design of Floating Platforms for Southeast Asia
Riser VIV Suppression
Ringing of Offshore Platform
Future Work
Conclusions
33
CFD Application: Ringing of Steel Gravity Base Structure (SGS)Remote location (NW Australia Shelf)Moderate water depth < 100mExtreme metocean criteria (100 year cyclone)
Coauthors: Jang Whan Kim / Jaime Tan
http://www.offshoreenergytoday.com
Overview – Ringing Phenomenon
In designing offshore platforms located in severe wave conditions, the potential resonance response of the hull structure due to wave loads must be checked.
Conventional wave load analysis based on linear wave theory does not fshow dynamic amplification.
Steep waves are non-linear and may contain significant energy at higher harmonics of fundamental frequency.
Forcing frequency of the higher-harmonic non-linear wave load ~ natural frequency of the structural vibration
=> ringing occursg g
35
Computing Resources
BoxClusterDSN
CPU: Intel® Xeon® L5520 x 2 per node, 2.26GHz
Memory: 96GB (host), 48GB (client)
( ) G ( )HDD: 1TB (host), 250GB (client)
OS: Red Hat Enterprise Linux 5
RAID box - QNAP TS-879U-RPRAID box QNAP TS 879U RP
Amazon Elastic Compute Cloud
On-demand instances, USD2.40 per hour
Cluster Compute Eight Extra Large 60.5GB memory, 88 EC2 Compute Units
2 x Intel® Xeon® E5-2670, 8-core “Sandy Bridge” architecture), y g )
OS: SUSE Linux Enterprise Server
CFD Simulation of Short-Crested SeasImplementation of Absorbing Boundary Conditions
37
Ringing Analysis Methodology1.
CFD analysis calculates dynamic
pressure onpressure on structure
2. M d l l i5. Modal analysis
simulates dynamic structural response
of structure
5. Structural analysis using ringing loads
3. Approximation
4. Calibration of short- Approximation
method calculates ringing response from model test
Calibration of short-duration CFD-modal analysis
results
Footer can
be customize
38
Table of Contents
Technip Introduction p
R&D on Floating Platforms
Early CFD ApplicationsEarly CFD Applications
Design of Floating Platforms for Southeast Asia
Riser VIV Suppression
Ringing of Offshore Platform
Future Work
Conclusions
39
Tandem Riser VIV Tests – Phase 3
An improved set-up for testing VIV of multiple risers.multiple risers.
Performance of fairings in tandem
Tests ongoing at UTM
CFD Analysis ramping up Towing directionramping up Towing direction
Two-Body Interactions
West Alliance TADWest Seno TLP
41
Experiments at NU Singapore (Jimmy Ng/ John Halkyard)Simplified Model of Kikeh Spar+TAD Column (200 scale)
Study Wave/Wake Interactions
Tow the (fixed) cylinders in regular waves
Measure the force on the downstream cylinder section
sTsmU
UTDS
s
492PeriodSheddingVortex/05.0SpeedCurrent
18.0Number Strouhal
×====
===
mdmDsTs
075.0diameter Cylinder Small166.0DiameterCylinder Large
4.92PeriodSheddingVortex
====
×==
1.5D
0.6D
5 cycles/(47s)
44
Future Work
Future applications for Gen-Y offshore engineers: Use CFD to replace aging baby-boomer’s empirical know-how. p g g y pDo things the towing tank cannot do.
Solve realistic oceanic flows with sheared currents with variable temperature density and directiontemperature, density and direction. Address scaling effects of model test results. Include dynamic structural response through FSI (mapping to dynamic structural model of TLP)
Wind loads on offshore structures topsidesUseful for initial design estimatesUse u o t a des g est ates
45
Conclusions
CFD applications gaining from advances in software/hardwareSignificant advances being made solving difficult problems w/CFDLocal know-how in Malaysia is improvingBuilding CFD capability is a good use of local resources Capability to address VIM has advanced from single column (Spars)Capability to address VIM has advanced from single column (Spars) to include multi-column floating platformsFree surface applications with VOF approach allows calculation of higher-order wave loads for resonant structure behaviorhigher order wave loads for resonant structure behaviorCFD results complement/complete model testsNow possible to perform short-crested random wave simulations
More realistic and less conservative approachBenchmarking still required to assure reliable resultsFuture work involving multiple bodies is needed to addressg p
Behavior of multiple risers/fairingsInteractions of 2 floating bodies in current+waves
46
Thank you!
Shell Sabah Petroleum and Technip for permission to show the model testsShell Sabah Petroleum and Technip for permission to show the model testsJaime Tan for carrying out the Star CCM+ CFD AnalysisJang Whan Kim for Ringing AnalysisCD Ad f S ki O t it
www.technip.com
CD-Adapco for Speaking Opportunity