Numerical workflow for autonomous synthesis of vertical axis wind turbine blades.
Blades shape is synthesized for maximum annual energy production.
For different locations the workflow synthesizes different shapes.
The workflow can invent new shapes (without a resembling initial shape).
Several case studies are presented with promising results.
This paper presents a numerical workflow designed and developed for autonomous synthesis of vertical axis wind turbine (VAWT) blades for maximum annual energy production at a specified location given by specified wind speed distribution and prescribed tip speed ratio. The workflow can synthesize shapes of both classical VAWT designs: Darrieus and Savonius rotors. This is achieved using a novel shape parameterization scheme based on B-splines which represents a compromise between shape generality and the multitude of shape variables. The developed computational framework enables the optimizer to synthesize and evaluate a variety of geometrically and even topologically different shapes such as the Darrieus and Savonius types. Moreover, the workflow can invent (i.e. numerically generate without a resembling initial shape) new generic shapes for custom operating conditions. Both single wind-speed and systems related to real-site operating conditions specified by a given distribution of wind speeds are considered. The developed workflow consists of efficient geometry parameterization, a genetic algorithm based optimizer and a computational fluid dynamics based simulator. The rather promising results of custom-shaped vertical axis wind turbines for maximum annual energy production at a given specific site are presented using a set of case studies.