76th Annual Meeting of the Division of Fluid Dynamics
Sunday–Tuesday, November 19–21, 2023;
Washington, DC
Session A24: Energy: Wind Power
8:00 AM–9:57 AM,
Sunday, November 19, 2023
Room: 150A
Chair: Nicholas Hamilton, National Renewable Energy Laboratory
Abstract: A24.00007 : Effects of blade fouling on performance of vertical axis wind turbines*
9:18 AM–9:31 AM
Abstract
Presenter:
Yuri Kanash
(Reykjavik University)
Authors:
Yuri Kanash
(Reykjavik University)
Maxon Montstream Quas
(Reykjavik University)
Laura Stebig
(INSA Lyon)
Emilie Peridon
(ENSTA Bretagne)
Raul B Cal
(Portland State University)
Armann Gylfason
(Reykjavik University)
Wind energy is seen as one of the most attractive energy sources for the future and has witnessed rapid growth in capacity in recent years; however, it is still facing significant challenges. Harsh weather conditions such heavy rain, sandstorms and wind gusts all negatively impact the turbines’ power production and its life span. Efficiency is reduced through particles contaminating the incoming airflow causing blade fouling, altering surface and mechanical properties of turbine blades. Present study investigates the ramifications of blade fouling affecting various rotor configurations of Vertical Axis Wind Turbines (VAWTs) to reduce and/or prevent the impact of harsh weather on the rotor. This is accomplished through controlled physical experiments recording the torque produced by a rotor which has experienced fouling. Impacts of particles with the blades at various angles of rotor rotation and simulated operating conditions are detected by a high-speed camera system. Particle trajectories prior and after impact are determined with Lagrangian particle tracking techniques and form the basis for design of test blades representing various amounts of fouling. The small-scale nature of the physical experimental models necessitates fine control over torque losses within the testing equipment. Magnetic levitation is introduced aiming to minimise bearing friction along with Eddy Current Braking (ECB) for frictionless speed control of the rotor. Voltage supplied to the ECB is calibrated against the braking force the system is applying for a given rotor angular velocity using wind tunnel tests and verification with a pendulum setup. Information regarding the amount of braking applied is then used in determining the torque said rotor is producing as well as a means for closed-loop speed control. Each component of the test equipment is evaluated individually, recording associated torque losses discretely, permitting a modular configuration of experiment-tailored systems. Allowing the same components to make up systems being tested in a variety of environments such as urban and water-based turbine installations among others. Knowledge obtained in the present experimental campaign then forms the basis for design and optimisation of damage mitigation strategies and systems to be incorporated into VAWTs.
*The Icelandic Research Fund Grant 228692-052