Experimental research on the compression failure of wind turbine blade trailing edge structure

ABSTRACT

The wind turbine blade trailing edge (TE) is frequently exposed to compressive loading and can even be damaged under complex operating conditions. Among the most typical TE failure modes is the adhesive-joint failure, so it is necessary to evaluate the structural behavior of the adhesive joints in TE under compressive loading. In this regard, an improved testing method was proposed for blade subcomponents. Specifically, the experiment was performed on a composite TE structural specimen under compressive loading to reveal its internal failure mechanism. The results showed that when the TE specimen was compressed under increasing load, buckling deformation occurred gradually at the sandwich laminates. Also, the bending deformations of the laminates on the suction and pressure sides were different in the bonding region. The resultant shearing effect led to the structural adhesive undergoing brittle fracture, which then triggered debonding and extension, finally causing the debonding failure of the trailing-edge specimen. To guarantee the safety of a blade under edge-wise loading, it is suggested that the structural strength of the TE should be emphasized during the blade design process.

KEYWORDS:

• Composite
• trailing edge
• failure analysis
• wind turbine blade

Acknowledgements

The authors gratefully acknowledge the financial support from the National Key R&D Program of China (NO.2018YFB1501201). We would like to thank anonymous reviewers for their valuable suggestions to this work.

Author contributions

Honghui Wu conducted the analysis of the key issues and partly finished the experiment and manuscript. Liangwen Qi and Jing Qian analyzed the experimental data and wrote the manuscript in part. Huijing Cao, Kezhong Shi and Jianzhong Xu critically revised the paper and provided constructive criticism.

Disclosure statement

No potential conflict of interest was reported by the author(s).