Buckling Reliability Analysis of Wind Turbine Blades with Trailing-Edge Adhesive Voids Using the Response Surface Method

Trailing-edge adhesive voids are typical manufacturing defects that affect wind turbine blade stability. This study investigates the influence of the spanwise location and length of missing-adhesive voids on the buckling reliability of a 90 m composite wind turbine blade. BUCKLE eigenvalue analysis was used to determine the initial geometric imperfection mode, and the modified Riks method was employed to evaluate geometrically nonlinear buckling. For a void centered at 75 m with a length of 400 mm, the BUCKLE and Riks factors for the medium mesh were 0.4386 and 0.3822, respectively. For the prescribed defect cases, eight uncertain material and geometric inputs were considered. A full quadratic response surface including pairwise interactions was developed from an 81-point central composite design, and Monte Carlo simulation and total-effect Sobol sensitivity analysis were used to assess failure probability. For this blade and loading pattern, the sampled void centers at 75 and 80 m had relatively low capacities, while increasing void length reduced capacity and shifted conditional failure-probability curves toward lower load factors. These location-specific results support defect prioritization, not a universal critical region or a certified reliability level.