General course objectives
To be able to calculate hydrodynamic and aerodynamic loads specific for offshore wind turbines.
- Design codes for bottom fixed offshore wind turbines. Design basis for wind and wave climate. Extreme value prediction by fitted distributions.
- Substructure types for offshore wind turbines. Design of a substructure.
- Hydrodynamic loads from linear irregular waves. Wave kinematics and the Morison equation. Wheeler stretching and the MacCamy Fuchs diffraction theory. Simplified aerodynamic load model.
- The 1P and 3P dynamic criteria and basic technique for fatigue calculation.
- Wake aerodynamics and vortex structures behind a wind turbine rotor. 1D momentum theory for wakes. Wake interaction in wind farms. Methods for computation of wakes in wind farms.
- Introduction to planning and environmental decisions for offshore wind farms. Introduction to operation and maintenance management for offshore wind farms.
- Basic concepts for floating wind turbines and calculation of mooring forces. Linearised equations of motion for floating wind turbines. Dynamic stability and control of floating wind turbines.
Matlab skills equivalent to course 02631/02633. This level of Matlab skills is essential to carry out the course reports. 41106. Fluid Mechanics equivalent to course 41312 or 41101. Numerical Analysis equivalent to course 02601. 46300 - can with some effort be taken concurrently.
A student who has met the objectives of the course will be able to:
- Describe the typical foundation types for bottom-fixed offshore wind turbines and summarize the content of the IEC 61400-3 design norm
- Apply the elements of a design basis and use statistical data to determine e.g. a 50-year sea state
- Calculate a force time series from linear irregular waves and determine which forces that dominate
- Explain the basic dynamics of bottom fixed offshore wind turbines, the method for fatigue calculations and perform a simple substructure design
- Apply 1D momentum theory for analysis of wind turbine wakes
- Implement closed-form wake models in Matlab
- Analyse the production in rows of wind turbines with application of closed-form wake models and determine the optimal spacing between the wind turbines
- Describe the basic process in planning an offshore wind farm and the interaction between the involved parties
- Understand and suggest simple strategies for operation and maintenance
- Derive the equations of motion for typical floating wind turbine configurations
- Implement time domain models for the dynamics of floating wind turbines subject to wind and wave forcing
- Analyse the dynamic stability of floating wind turbines and propose modifications of the control system to improve stability