Blade Element Momentum simulations using polars extracted from wind-turbine-model experiments

• Autor(a) principal: Rodrigues, Pedro Trombini [UNESP]
• Data de Publicação: 2021
• Outros Autores: Lemos, Diego Magela, Pagani Júnior, Carlos do Carmo [UNESP], Sampaio, Daniel Souza [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/235009
• topic: Computational fluid dynamics; Turbulent boundary layer; Energia eólica; Aerodinâmica; Fluidodinâmica computacional; Camada limite turbulenta

Due to rotational effects, the observed load of inboard sections of rotary wings is consistently higher than the load predicted based on the two-dimensional aerodynamic behavior of the corresponding airfoil in linear motion. Therefore, engineering methods used to analyze and optimize the aerodynamics of horizontal-axis wind turbines (HAWT) rely on corrections to 2D airfoil data. Since the physics associated with the phenomenon is not fully understood, the correction models have to resort to empirically determined parameters. It is important to stress that a great scattering of the turbine power predictions based on different correction models is observed for conditions of high blade load. We propose a methodology to predict the load on HAWT blades based on the widely applied blade element momentum (BEM) method that does not rely on the correction of 2D polar curves. In the proposed methodology, the force coefficients are stored in the lookup table and consulted by the BEM algorithm, not only as function of the angle of attack but also as function of the chord-to-radius ratio and the local Rossby number. The data of the lookup table is provided by the measurements of the unsteady aerodynamic experiment Phase-VI, coordinated by the United States' National Renewable Energy Laboratory and conducted in a 24.4m × 36.6m wind tunnel in NASA Ames Research Center. Compared to a well accepted correction model, the proposed methodology predict the load radial distribution with greater accuracy for relatively high wind speeds.