Trailing edge subcomponent testing for wind turbine blades–Part A: Comparison of concepts

Abstract

As a complement to the mandatory structural full‐scale test for wind turbine blades, the method of subcomponent testing has recently been proposed by international standards and guidelines for the experimental investigation of design‐critical full‐scale parts. This work investigated different subcomponent test (SCT) concepts for a trailing edge of an outboard segment from a 34‐m blade. Detailed analytical models to design the SCT concepts with regard to the boundary conditions were derived. Finite element analyses of the SCT's linear response were benchmarked against each other and against the full blade model in terms of displacements, rotations, in‐plane strains, and energy consumption. All SCT concepts were in good agreement with the full‐scale test with respect to the longitudinal strain response but showed deviations in the transverse and shear strain, as well as in the rotational and displacement response.

Understanding progressive failure mechanisms of a wind turbine blade trailing edge section through subcomponent tests and nonlinear FE analysis

“…This is the first-of-its-kind study particularly focusing on the failure of trailing edge sections to the best of our knowledge. In addition, the FE model presented in this study is more detailed and accurate in predicting the failure sequence and multiple failure modes of trailing edge sections comparing to existing studies [9,11].…”

“…Typical failure modes observed in full-scale blade tests includes adhesive joint debonding, sandwich core failure and composite laminate failure. In recent years, subcomponent testing has been used [6][7][8][9][10] to understand the structural behavior of critical parts of composite blades. The subcomponent testing could be an important complement to the full-scale blade tests that are mandatory for certification of wind turbine blades.…”

“…The subcomponent testing could be an important complement to the full-scale blade tests that are mandatory for certification of wind turbine blades. Regarding the subcomponents of trailing edges, efforts have been made to elaborate benefits of subcomponent over full-scale testing [8] and comparing different subcomponent test concepts [9]. Recent work [11] has assessed the failure of trailing edge subcomponents by addressing structural instability associated with pre-buckling and post-buckling response.…”

“…The aforementioned studies [8][9][10][11] provide valuable knowledge on the structural response of trailing edge sections in the subcomponent tests. Nevertheless, two important questions remain.…”

“…Several layers of solid elements are used along the thickness direction of the trailing edge panels to better capture through-thickness stress/strain components in both sandwich skin laminates and foam core materials. The presented solid element model is much more detailed than the shell element models that have been used in other studies [1,3,5,9,11].…”