New Design Guidelines for Slug Loading and Response in … · 2014. 4. 1. · New Design Guidelines...
Transcript of New Design Guidelines for Slug Loading and Response in … · 2014. 4. 1. · New Design Guidelines...
New Design Guidelines for Slug Loading
and Response in Pipelines and Risers
MCE Deepwater Development 2015, London
Slug Loading and Response
SLARP Phase 2 Testing
A-frame Supports
Lazy-S RiserTypical Riser Base Spool Problem
Slugging Problem Definition
Steady flow = Constant force
Slug flow = Time varying forces
− Varying fluid mass (heavy vs light)
− Varying fluid forces at bends
− Varying pressure, friction, Coriolis, etc.
Fatigue and overloading can occur
if slug flow is coupled with onerous
frequencies, dynamics and susceptible
configurations
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Phase 1: Kick-off April 2010
Phase 2: Completed 2014
Phase 3: Commenced 2014
⇒ Schedule for completion Q1 2016
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Slug Loading and Response
in Pipelines and Risers
⇒ Global structural response
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2
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Participation
Phase 1: Desktop Analysis
BP, BSEE, Chevron, ExxonMobil, Petrobras, Saipem,
Technip, Total, GE-Wellstream
Phase 2: Testing & Analysis
BP, BSEE, Chevron, ExxonMobil, Petrobras, Saipem,
Total, GE-Wellstream
Phase 3: Further Testing & Analysis
BP, Chevron, Saipem, Total
⇒ Confirmed to date…
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Collaboration
Supported by a wide range of
collaborating organizations
Working together to achieve a
common GOAL
Establish industry consensus on
methodologies for analyzing structural
response of pipeline & riser
configurations subject to slug flow
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Analytical formulation & methodologies
Communication of flow data
Global response to bend forces
Enhanced numerical modelling
Multi-planar configurations
Response coupling
Breakup & vertical flow
Viscosity effects
Resonance effects7
Phase 1
Phase 2(Testing)
Phase 3(Testing)
Targeted Uncertainties
Phase 2 Testing
4.5” horizontal U-piece
A-frame vertical supports
Single shot water slugs
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Southwest Research
Institute (TX, USA)
− Wide range of slug velocities
(4 m/s to 15 m/s)
− Testing performed in air
− Slugs propelled using
Nitrogen from an inclined
loading beam
− Slug lengths between 20 m
and 30 m considered
− Various support conditions
Test Results and Findings
Enhanced numerical model developed to replicate
changing length & velocity of slugs
Excellent correlations achieved
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Dynamic displacement of piping
system due to slug flow
Horizontal racking
displacement of U-piece
String potentiometer
for displacement
measurement
Numerical model
correlation
Physical Model vs Numerical Model
Pipe Displacement Time History
CFD correlation
SLARP Design Guideline
Problem Definition & Context
Latest Design Methodologies
Detailed Guidance on:
Flow data transfer (flow assurance to SURF)
Flow data assessment (qualitative & quantitative)
Iteration and optimization (analysis approach and configuration)
Monitoring of Structural Response
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SLARP Methodologies
Preliminary:
− Flow data sorted into groups
− Regular slug analysis performed for
representative slug units (regular train)
− Slug units can be fixed or variable
Intermediate:
− Detailed load definition (e.g. 4 hr
slug flow time history)
− Irregular slug train
− Random slug train
− Fixed or variable slug units
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Complex
− Coupled CFD-FEA
− Fluid structure interaction
− Demanding simulations
Intermediate Approaches
Slug Train Analogy…
Irregular slug train setup based on
specific flow assurance (FA)
simulation window
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Flow Assurance Input Data
Tabulated global input data
Liquid slug start times staggered as
per flow simulation window(s)
Regular Train = Consecutive identical units
Sample time history table - Time stamp example format:
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Slug Unit No.Entry Time
(s)
Liquid Slug Pocket (or Bubble)Slug Unit Velocity
(m/s)Length (m)Equivalent
Density (kg/m3)
Length (m)Equivalent
Density (kg/m3)
1 0 100 700 200 200 5
2 100 60 825 150 225 6
3 200 80 750 125 215 3
4 300 120 675 175 205 8
¦ ¦ ¦ ¦ ¦ ¦ ¦
¦ ¦ ¦ ¦ ¦ ¦ ¦
Populate table with all slug units identified in flow assurance prediction analysis window (e.g. 4 hrs, 12 hrs, 18 hrs)
e.g. 4 hrs
Irregular Slug Train
Each slug unit can be different
Different representative slug unit
velocities can be assigned to slug units
Train carriages can join,
separate & change length!
Variable slug units are also possible, i.e.:
Slug units can change properties during transit
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Slugging Fatigue Damage
First calculate for simulation window
e.g. 4 hrs, 8 hrs or 12 hrs
Then extrapolated to window of operation
e.g. 12 months
Compare to slugging fatigue budget
(or total calculation)
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Slugging?Other fatigue mechanisms
Phase 3 – Latest Scope of Work
Testing with continuous flow setup
Testing of multi-planar configuration
Numerical model correlation
SLARP Design Guideline update
Worked examples
Field data correlation study
Detailed monitoring system review16
Final details
being worked
Subject to final
participation
numbers
Summary
Summary
SLARP Design Guideline represents
a significant forward step as the 1st
collaborative industry guideline
relating to slug loading & response
methodologies in pipelines & risers
Successful correlation of full scale test
response results with numerical model
predictions for a range of conditions
Phase 3 (now ongoing) will significantly
expand current insights & model validation18
MCE DD 2015 – Thank You!
Presenter:
Jason Payne, Wood Group Kenny Ireland
Senior Project Manager – Technology Team
Co-authors:
− Adrian Connaire & Christian Chauvet, WGK
− Steven Green, Southwest Research Institute (SwRI)
Acknowledgments:
− SLARP JIP Participants - BP, BSEE, Chevron, ExxonMobil, GE-
Wellstream, Petrobras, Saipem, Technip, Total
19www.slarp-jip.com