A generic evaluation of loads in horizontal axis wind turbines

This paper forms part of a PhD research programme aiming to search for systematic trends in loads as influenced by: wind conditions (mean wind speed, turbulence intensity), design properties of wind turbines (mass, stiffness and turbine scale) and key design parameters (design tip speed ratio, for example). Within the scope of this paper an investigation is made of how blade mass and stiffness affect trends in lifetime damage equivalent loads (DEL) of the rotor blade root fatigue loading (as may influence hub design). Clearest results emerge where the mass and stiffness are changed proportionally so as to maintain the natural frequency. This is perhaps because any substantial changes in the design parameters of a wind turbine are likely to demand a retune or re-design of the control system. A preliminary study of the influence of wind turbine scale was also considered based on scaling with similarity