Session: 09-02-06 Wind Energy: Dynamic Analysis II

Submission Number: 180862

Dynamic Analysis of a Floating Offshore Wind Turbine Under Turbulent Wind and Various Sea States 

Floating offshore wind turbines (FOWTs) operate in complex marine environments where wind and sea states significantly influences the platform motion, aerodynamic loading, structural response, and power performance. Understanding the dynamic interactions in the aero-elasto-servo-hydrodynamic coupled system is essential for improving the accuracy of simulation tools and optimizing turbine design. However, fully coupled simulations are often computationally intensive.

This study conducts a detailed dynamic analysis of the IEA 22MW offshore reference wind turbine under two configurations: (1) the turbine is coupled with a semisubmersible floating platform subjected to complex sea states under wind precursor, and (2) the turbine is fixed, but subjected to the equivalent prescribed platform motions derived from the coupled simulation. The second configuration can help to assess how floater response in complex environment affects the wind turbine performance while using fewer and faster simulations, especially in the preliminary design process. Moreover, applying wind precursor to the FOWT in a farm facilitates accurate prediction of wake development, turbine loading as well as platform motion.

First, simulations of the floating system are carried out using FAST.Farm, a mid-fidelity engineering tool used to simulate wind farms, predict power performance, and analyse structural loads by considering the interactions between individual turbines and the wind. Wind fields generated from the atmosphere boundary layer solver is used as precursors for the floating offshore wind farm simulation. The resulting platform motions are then imposed as prescribed inputs to the fixed wind turbine. Moreover, the prescribed motion applied on the fixed wind turbine is evaluated with high-fidelity computational fluid dynamics (CFD) simulation. Aerodynamic loads and power output are compared across these two configurations. Additionally, simulations under various sea states are conducted to assess the wind turbine performance.

In this work, dynamic response of a FOWT has been investigated considering various sea states and realistic boundary layer turbulence for wind. The results show that applying prescribed motion to a fixed wind turbine can approximate a fully coupled floating system with sufficient accuracy. This approach offers a promising path to streamline the early design phase of FOWTs by reducing computational costs while maintaining reliable performance predictions.

Presenting Author: Xiaoqin Zhang Institute of high performance computing

Presenting Author Biography: Dr. Zhang Xiaoqin is a senior scientist in institute of high performance computing. Her primary research interest lies in wind turbine and farm model in the marine offshore technology as well as CFD simulation of ship propulsion system.

Authors:

Xiaoqin Zhang Institute of high performance computing
Quang Tuyen Le Institute of high performance computing
Xiuqing Xing Institute of high performance computing
Xin Lu Institute of high performance computing
Xiang Zhao Institute of high performance computing