(OC3) Phase III

IEA Annex XXIII
Offshore Code Comparison Collaborative (OC3)
Phase III – Tripod
Finite Element and Multibody Simulation of the
Support Structure Dynamics of OWECs
M. Kohlmeier, T. Kossel, and W. Zielke
ForWind – Center for Wind Energy Research
Institute of Fluid Mechanics
Leibniz Universität Hannover
9th Full Committee Meeting, Ramboll Wind Energy Esbjerg, Denmark
Esbjerg, September 12, 2008
Contents
ƒ
Motivation
ƒ
Waves and Wave Load Simulation
ƒ
Integrated Modelling of Offshore Wind Energy
Converters (OWECs)
ƒ Simulation approach for multibody modelling
ƒ Finite element analysis of OC3 tripod
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Motivation
ƒ Integral Modelling
ƒ Interactions
ƒ Time domain analysis of
the support structure including
wind and wave loads
ƒ Turbulent wind fields
and their aeroelastic interaction
with the rotor dynamics
ƒ Impacts
ƒ Design wave
H, T
ƒ Flexibility according
to chosen type of
support structure
ƒ Stochastic simulation
ƒ Tailored sequence
H, T
ƒ Fast and reliable methods
- simplified vs. complex approaches
- individual optimization
Hs, Tp
ƒ Commercial and internal codes
- Ansys, MD Adams, MD Nastran etc.
- Fast/AeroDyn, WaveLoads
- Poseidon, aeroFLEX etc.
Hs, Tp
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Wave and Wave Load Simulation
4
WaveLoads: Standard Modelling Procedure
1. Water Surface Elevation
2. Water Particle Velocities
3. Distributed or Integrated
Loads for Finite Element or
Multibody Simulation
5
WaveLoads: Pre-Processing & Modular Application
Batch Processing
Visualisation
Finite Element Simulation
Graphical User Interface (GUI)
OpenGL Visualisation
Dynamic Link Library (DLL)
6
Integrated Modelling of OWECs in Finite Element
and Multibody Simulations
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Motivation – Dynamic Analysis of the Support Structure
ƒ Monopile vs. Jacket
ƒ Sea states of waves travelling in
differently distributed directions
ƒ Measurement vs. Simulation
- measuring platform Fino 1
- measuring mast
„Amrumbank West“
ƒ Consideration of
- Offshore wind park
„alpha ventus“
turbulent wind fields
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Multibody Dynamics Including Wind and Wave Load
Models in MD Adams
9
Multibody Dynamics Including Wind and Wave Load
Models in MD Adams
ƒ
Flexible and modular modelling approach
ƒ
Aim: optimization of different support structures
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Modules for Multibody Simulation in MD Adams
Model Set-up
ƒ
Fast – Aeroelastic Design Code for Horizontal Axis Wind Turbines
(NREL, Jason Jonkman)
Fortran 90, DLL
ƒ
Controller for torque and blade-pitch
Fortran 90, DLL
Interaction with the Wind Filed
ƒ
AeroDyn – aerodynamics software library
(NREL, David J. Laino)
Fortran 90, DLL
ƒ
TurbSim – A stochastic, full-field, turbulent-wind simulator for
use with the AeroDyn-based design codes
(YawDyn, FAST, and MSC.ADAMS®)
(NREL, Neil Kelley and Bonnie Jonkman)
Fortran 90
(NREL - National Renewable Energy Laboratory)
Impact of the Waves
ƒ
WaveLoads – Wave loads resulting from the current sea state
acting on the support structure supposed to be
hydrodynamically transparent
(LUH, Kim Mittendorf, Nguyen Ba, Martin Kohlmeier)
C++, DLL
Foundation
ƒ
Soil Model – Supply of material data for linear and nonlinear soil modelling
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DLL
Overview of Source Code used in MD Adams Model
Creation of „Adams.dll“ for linking with MD Adams
ƒ
FAST
– Fortran 90
ƒ AeroDyn
– Fortran 90
ƒ Adams2AeroDyn – Fortran 90
Adams.obj
ƒ
Fast2WaveLoads – C
Fast2WaveLoads.obj
ƒ
WaveLoads
WaveLoads.lib, WaveLoads.dll
–
C++
ƒ
Adams.obj
ƒ Fast2WaveLoads.obj
ƒ WaveLoads.lib
Adams.dll
DLLs to be applied in Adams Model:
ƒ
Adams.dll
ƒ WaveLoads.dll
ƒ Controller.dll
Remark: MD Adams R3 may use multiple DLL files.
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WaveLoads Pre-processing for OC3 Modelling
ƒ
Finite Element Modelling
ƒ Ansys
ƒ MD Nastran
ƒ Abaqus
ƒ
WaveLoads
ƒ
Multibody Dynamics
ƒ MD Adams
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Multibody Simulation in MD Adams
- Current Status -
ƒ
Final Step: Assembly
ƒ wind turbine (right)
ƒ tripod support
structure (below)
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Finite Element Simulation in Ansys
ƒ
OC3 Tripod Support Structure
ƒ Rigid (2.6) / Inverted Pendulum (4.3)
ƒ No Buoyancy
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rev5_NoBuoyancy_2.6_M01N01Fx
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rev5_NoBuoyancy_4.3_M01N01Fx
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rev5_NoBuoyancy_2.6_M19N19Fz
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rev5_NoBuoyancy_4.3_M19N19Fz
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rev5_NoBuoyancy_2.6_M53N47Fy
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rev5_NoBuoyancy_4.3_M53N47Fy
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Current Model
Further Research Aims
Consideration of
Turbulence Effects
Wind Loads
- Blade Element – Momentum
Method [AeroDyn]
Structural Response
- Finite Element Simulation
[Ansys, MD Nastran, Abaqus]
- Multi-body Dynamics
[MD Adams]
5-MW Reference Wind Turbine
for Offshore System Development
(Jonkman, Butterfield, Musial,
and Scott, April 2008)
Wave Loads
- Regular or Irregular Waves
- Sea Sates
[WaveLoads]
Consideration of Different
Types of Joints
Analysis of Support
Structur Concepts
- for 5-MW OWECs
- Design Optimisation
Influence of the Foundation
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Thank you for your attention.
www.forwind.de
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