The Fraunhofer Institute for Applied Solid State Physics IAF announced that it has developed an innovative radar scanner that can detect defects in the composition of wind turbine blades with far greater accuracy and with a visualized cross-sectional view.
The Fraunhofer Institute has developed a radar scanner to find defects in
plastic wind turbines. (Franunhofer Institute)
The turbine blades are generally composed of glass fiber- and carbon fiber-reinforced plastics and this new technique offers cost-savings in production and operations.
“For a single blade, up to 100 sheets of glass fiber webbing are layered on top of each other, shaped and then glued together with epoxy resin,” the announcement stated. “Quality control is essential at this stage in production.”
The glass fiber sheets have to be layered without undulations or folds to avoid the formation of lumps of resin or sections that were not set properly with the epoxy. Using infrared thermography, the Fraunhofer Institute can see these defects, as well as possible delaminations or fractures, quickly and on a large scale.
“At the core of the material scanner is a high frequency radar, which operates in the W band between 85 and 100 GHz with only very few watts of transmitting power,” the article continued. “Specialized software is then used to process the transmitter and receiver signals and visualize the measurement results.”
This scanner is based on indium gallium arsenide semiconductor technology and is no larger than a package of cigarettes. Beyond manufacturing savings, the scanner will also assist with maintenance of the blades by allowing workers to classify the extent of defects or issues.
The researchers believe that this technology could also be applied to other manufacturing processes that use similar materials, such as the aerospace industry.
Fraunhofer will present this new technology at the Hannover Messe from April 24-28.