To investigate the effects of pre-bend and varying backward swept geometrical design on the aeroelastic loads of flexible wind turbine blades
a rotation matrix was utilized to accurately describe the airflow velocity
blade displacement
orientation and vibration velocity at blade elements
which were introduced to modify the blade element momentum model and ultimately form an aeroelastic simulation model. Based on the DTU 10 MW blade
three blades with different backward swept geometries were designed
and static
dynamic
and aeroelastic coupling analyses were conducted on each blade variant. The study explores the effects of bend-twist coupling deformations on the blade angle of attack and the influence of increased aerodynamic force arms due to pre-bend and backward swept geometric design on root torque. The study reveals that the bend-twist coupling effects of the blades are significantly influenced by the blade's geometric shape. The backward swept blade shows the best performance in reducing flap-wise root fatigue loads by up to -11.14%
albeit significantly increasing the torsional root fatigue loads. Conversely
the pre-bend blade demonstrates a decrease in both flapwise and torsional root fatigue loads.
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