Today, the increasing energy demand and the need for clean power generation has lead to the
improvement of wind turbines and the development non invasive inspection techniques for the
assessment of wind turbine blades to maintain long term reliability as well as to avoid catastrophic
Given the complexity of the geometry, the material composition and material thicknesses, finding a
NDT technique to effectively and rapidly inspect the blades is a challenging task. Wind turbine
blades are fabricated using different materials like fiber glass, carbon composites, foam and/ or balsa
wood. Layers of these materials are bonded together using an epoxy type resin. Inspection of the
bond quality between external layers and structural elements of the blade is of fundamental
importance for quality control and service of the blade.
In this study our efforts towards the applications of Line Scanning Thermography (LST) for the
analysis of test coupons fabricated using the materials employed in the manufacture of wind turbine
blades, as well as some wind turbine blade sections. LST utilizes a line heat source to thermally
excite the surface to be inspected and an infrared detector to record the transient surface temperature
variation produced by disbonds, and other subsurface imperfections. The LST technique has
provided a quick and efficient methodology to scan large composite structures, which makes it
desirable for the inspection of wind turbine blades. The scanning protocols developed for the
detection of sub-surface disbonds (delamination) in coupons and parts will be presented. The
successes and limitations of the technique will be discussed.
© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Obdulia Ley and Valery Godinez
Feasibility of using line scanning thermography in NDE of wind turbine blades
", Proc. SPIE 7983, Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security 2011, 79831W (March 29, 2011); doi:10.1117/12.880095; http://dx.doi.org/10.1117/12.880095