Fedem Technology is able to simulate various types of wind turbines both onshore and offshore, including monopiles, turbines with jack-up, jacket or gravity base sub-structure, and floating turbines.
A complete structural model that includes soil and pile stiffness, foundation, tower, nacelle and rotor blades as flexible structures (FE-representations) can be fully integrated. A 3D soil model can be included in the analysis, if applicable.
The detailing level of the simulation model can be effectively changed during the work process for optimum fatigue damage assessment of critical components.
Experience from previous projects with drilling rigs, jacket platforms and offshore wind turbines with jacket structure, indicates that the response in the transition between structure and soil shows a dynamic behavior. This is highly affected by the stiffness and damping in the soil, structure and water, as well as the mass and added mass effects. Dynamic behavior and fatigue poses great challenges in the design, installation and operation of offshore turbines.
We have on behalf of Statoil examined how structural response and capacity of an offshore wind turbine is affected by variations in the mechanical soil properties. There is also studied to which level of degree the soil parameters must be described to achieve adequate reliability of this type of analysis. In this project we have worked closely together with geotechnical experts at NGI and Statoil.
In the project for Statkraft, we implement various wave models for actual water depths at Dogger Bank, and perform a screening of different concepts based on fully integrated numerical analyses of the complete turbine exposed to wind- and wave loads.
We are also involved in a benchmarking project for simulation tools for offshore wind turbines; OC4. The project is organized by the IEA (International Energy Agency) and goes until 2012, where benchmarking of turbines with jacket foundation and floaters are in focus. The project contributes to further document the quality of FEDEM as a suitable software for simulation of wind turbines.