Modern wind farms are composed of arrays of wind turbines with a propeller design. However, the rotors interfere with each other, and the energy extracted per turbine is lower than if they were operating in isolation. As a result, the turbines are spaced far apart and cover larger areas. A solution might be to use Vertical Axis Wind Turbines (VAWTs) - the rotor blades spin around an axis perpendicular to the ground, since recent studies indicated that VAWTs exhibit the opposite behaviour, when composed in wind farms. They increase each other’s performance. Yet, VAWTs have a lower efficiency in isolation than current propeller design. The question arises; is a wind farm with VAWTs more efficient than the present design? If true, for what layouts is this valid? This project performed computer simulations of a pair of VAWTs in 24 different layouts, and the computer model was validated against experimental data in literature. A supercomputer at University of Oxford and pooled computers at Oxford Brookes were utilised to solve the billions of equations, and the total simulation time was beyond 12,000 hours. Results showed performance augmentations of up to 15%, which is in great contrast to modern wind farms, which experience a decrease down to 50% for the backrow turbines. VAWTs could potentially replace the current design, since the findings indicated that the wind farm would no longer be limited by the efficiencies of each individual turbine, but instead be limited by the amount of energy available at the given site.
Permanent link to this resource: https://doi.org/10.24384/fjh3-5689
Hansen, Joachim Toftegaard
Faculty of Technology, Design and Environment
Year: 2020
© Hansen, Joachim Toftegaard