Finite Element and Multibody Simulation of the Support

Finite Element and Multibody Simulation of the Support

IEA Annex XXIII
Offshore Code Comparison Collaborative (OC3)
Phase III – Tripod, Phase IV – Hywind
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
10th Full Committee Meeting, Risø National Laboratory, Denmark
Roskilde, March 13, 2009
Contents
ƒ
Motivation
ƒ
Wave Load and Support Structure Simulation
ƒ Pre-processing for Finite Element Simulation
ƒ Finite Element Analysis of OC3-Tripod (Phase III)
ƒ
Integrated Modelling of OWECs
ƒ Simulation Approach for Multibody Modelling (Phase IV)
ƒ Multibody Dynamics of OC3-Tripod / OC3-Hywind Spar-buoy
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Motivation
ƒ Integrated 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/Flex5, aeroFLEX etc.
Hs, Tp
3
WaveLoads: Pre-Processing & Modular Application
Batch Processing
Visualisation
Finite Element Simulation
Graphical User Interface (GUI)
OpenGL Visualisation
Dynamic Link Library (DLL)
4
Pre-processing for OC3 Modelling using WaveLoads 2.0
Finite Element Modelling
ƒ ANSYS
ƒ MD Nastran
ƒ Abaqus
WaveLoads Pre-processor
Multibody Dynamics
ƒ MD Adams
5
OC3 Phase III – Finite Element Simulation in ANSYS
ƒ
OC3-Tripod Support Structure
ƒ Inverted Pendulum (4.3)
ƒ Buoyancy Forces
6
Wind and Wave Load Modules Applied in MD Adams
ƒ
Flexible and Modular Modelling Approach
ƒ
Applicable on Different Types of Support Structures
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Multibody Dynamics
Simulation in MD Adams
ƒ
Current Modelling Status
Assembly Step:
ƒ Wind Turbine
ƒ Tripod Support
Structure
+
OC3-Tripod
1.5 MW NREL-Turbine
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Turbine on OC3-Tripod
simulated in MD Adams
Hydrodynamic Force Calculation using WaveLoads
in MD Adams
OC3-Tripod (Test Case for Phase IV)
ƒ Wave Loading and Buoyancy Forces
ƒ Loads Applied on the Structure in
Reference Configuration
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OC3-Phase IV
ƒ OC3-Hywind Spar-buoy Platform
ƒ Wave Loading and Buoyancy Forces
ƒ Loads on Moving and Deformed Structures
5-MW Reference
Wind Turbine
Further Developments Needed:
ƒ Wave Loading and Buoyancy
Calculation on Moving Sub Structures
(displacements, velocity and
acceleration of the member)
ƒ Incorporation of Mooring Lines or
Mooring System Properties
OC3-Hywind
Spar-buoy
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Current Model
Further Research Aims
Consideration of
Turbulence Effects
Wind Loads
- Blade Element –
Momentum Method
[AeroDyn]
Influence of Damping Effects
Structural Response
- Finite Element Simulation
[ANSYS, MD Nastran, Abaqus]
- Multibody Dynamics
[MD Adams]
Consideration of Different
Types of Joints
Wave Loading
- Regular or Irregular Waves
- Sea Sates
[WaveLoads]
Support Structure
and Foundation
Influence of Damping Effects
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Thank you for your attention.
www.forwind.de
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WaveLoads: Standard Modelling Approach
Water Surface Elevation
Water Particle Velocities
Distributed or Integrated
Loads for Finite Element or
Multibody Simulation
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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 Field
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
FAST
– Fortran 90
ƒ AeroDyn
– Fortran 90
ƒ Adams2AeroDyn – Fortran 90
ƒ
Adams.obj
ƒ
Adams.obj
Adams.dll
ƒ
Controller.obj
Controller.dll
Admas2WaveLoads – C
ƒ WaveLoads
– C++
ƒ
Adams2WaveLoads.dll
WaveLoads.dll
DLLs applied in the Adams Model:
Adams.dll
ƒ Controller.dll
ƒ Adams2WaveLoads.dll
ƒ WaveLoads.dll
ƒ
Remark:
MD Adams R3 may use multiple DLL files.
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