Simulação computacional de escoamentos bidimensionais sobre turbinas eólicas de eixo vertical

• Autor(a) principal: Faria, Geovanne Silva
• Data de Publicação: 2018
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/8933
• topic: Aerofólio; Turbina eólica; Coeficiente de sustentação; Coeficiente de arrasto; Coeficiente de potência; Airfoil; Wind turbine; Lift coefficient; Drag coefficient; Power coefficient; ENGENHARIA SANITARIA::RECURSOS HIDRICOS

The Brazilian energy matrix is highly focused on hydroelectric plants, that have been affected by lack of rain and long drought periods. It’s necessary to invest on alternative kinds of energy. The wind energy is an option, since Brazil presents winds with suitable velocity for energy generation, less than 5% of the Brazilian energy power grid is composed by wind turbines. The present work aims to contribute to the alternative energy generation industry, having as objective the study and analysis of flow condition over airfoils of vertical axis wind turbines. The simulation of flow over airfoils were performed using the Pseudo-Spectral Fourier method together with the Immersed Boundary method for discretization of the spatial domain, and the Runge-Kutta method of fourth order for discretization of the time domain. Both instantaneous and mean values were recorded for the lift (Cl) and drag coefficient (Cd), as well as the fields of vorticity, pressure and velocity for the flow over the airfoils with distinctive characteristics of form and angle of attack. It is concluded that with this first experiment, by refining the mesh, the values for Cl and Cd get close to the references. Posteriorly, it was imposed the movement of rotation of one vertical axis wind turbine, and simulated the flow over this turbine blades, when it was recorded both the instantaneous and mean values of the lift, drag and power coefficient, as well as the fields of vorticity, pressure and velocity for different values of velocities of turbine rotation for the airfoils NACA 0008 and NACA 4308. It was possible to conclude by analyzing the values of power coefficient (Cp), Cl and Cd obtained through simulation with the turbines that the airfoil NACA 0008 can be utilized for energy generation, since the airfoil NACA 4308 cannot be utilized in the adopted speed ranges.