Aero-structural design optimization of vertical axis wind turbines

In the last decade, vertical axis wind turbines acquired notable interest in the renewable energy field. Different techniques are available to perform aerodynamic and structural simulation of these complex machines, but, to the authors' best knowledge, a comprehensive approach, which includes an automatic optimization algorithm, has never been developed. In this work, a methodology to conduct an efficient aero-structural design of Darrieus vertical axis wind turbine is presented. This relies on a code-to-measurement validated simulation tool based on Blade Element-Momentum algorithm adopting a particular set of aerodynamic coefficients, and a code-to-code validated structural model based on the Euler–Bernoulli beam theory. The algorithms are coupled with a Genetic Algorithm to perform the optimization. The adopted decisional parameters allow to completely vary the blade shape and the airfoil geometry to reduce the structural stress and improve the aerodynamic performance. Different individuals are explored to perform a wide aerodynamic and structural analysis of improved configurations.