Analysis of a New Blade Design for a Vertical Axis Wind Turbine Called Flow Concentrator

There is wind energy in urban and rural areas that is not being used sufficiently; since the wind in these areas tends to be turbulent and slow. For this reason, this study is focused on the design and analysis of a vertical axis wind turbine based on the Darrieus type, which seeks to improve self-starting, since it is one of the main problems of this type of turbine. To achieve this, the study focuses on the first stage of self-starting, also known as static torque, which occurs at an angular velocity close to zero. This stage is essential for reaching the second stage of self-starting, known as dynamic torque. To do this, a two-blade 9W Darrieus-type turbine is designed and compared with the new blade design called “flow concentrator” considering the maximum height, maximum diameter, and chord of both as constants. The analysis is performed using the Double-multiple stream tube theorem (DMST), computational fluid dynamics (CFD), and by carrying out experimental tests. The results obtained are analyzed at different wind speeds, from 3 to 8 m/s, and at different azimuthal angle positions (0°, +45°, -45°, 90°), where a considerable improvement in self-starting of up to 100% is observed in its most optimal position.