Numerical modeling and simulation of horizontal axis offshore wind turbines.

Author(s)

Marielle de Oliveira

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Escola Politécnica (EP/BC)
• Defense date: 2023-06-02

Examining board members

Bruno Souza Carmo; Rafael dos Santos Gioria; Marcelo José Santos de Lemos; Francisco José de Souza; Flávia Schwarz Franceschini Zinani

• Advisor: Bruno Souza Carmo

Abstract

As global energy demand continues to increase, resulting in concerns over environmental pollution and energy crises, the use of renewable energy sources of energy has been encouraged to reduce the impacts caused by the use of fossil fuels. Among the renewable sources, offshore wind energy is a promising solution to contribute to energy supply due to several benefits, including higher and more consistent wind speeds compared to onshore locations. Offshore wind turbines are typically larger than onshore turbines, and to improve the efficiency and reliability of these large machines, numerical simulations have become an essential tool to predict the aerodynamic behavior of the full-scale wind turbine under different wind conditions, due to the limitations of experimental tests in representing the operating conditions of the system. Since the first high-resolution simulation of the flow around the wind turbine blades, extensive research considering different numerical methodologies have been conducted to understand the transient three-dimensional aerodynamic effects on the rotor blades. The suitability of each numerical method is determined based on the specific objectives of each analysis. To investigate the complete geometry of the wind turbine, including a high resolution of the blade geometry, simulations that resolve the flow around the turbine blades are crucial to enhance the ability to predict the wind turbine aerodynamics. Although the computational fluid dynamics (CFD) methodology has been proven effective in evaluating the transient aerodynamic behavior of the flow around wind turbine blades and generated wakes, only a few investigations using such method have considered the geometry of the full-scale prototype wind turbine in megawatt scale, due to the complexity of the numerical simulations and computational resources required. Therefore, to maximize the reliability of CFD methodology as a tool in offshore wind turbine development, this thesis provides a solid basis on the substantial impact of the numerical methods considered in the simulation setup on the accuracy of the results of the simulations and the associated computational costs. The analyses were conducted for two theoretical offshore wind turbines, the NREL 5 MW and IEA 15 MW. (AU)

• FAPESP's process: 18/26207-4 - Numerical modeling and simulation of horizontal axis floating offshore wind turbines
• Grantee: Marielle de Oliveira
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)