Active thermography for the interpretation and detection of rain erosion damage evolution on GFRP airfoils?

Defects such as voids, which may occur during the manufacturing of wind turbine blades, have a significant impact on premature rain erosion, especially at the leading edge. Active thermography offers the potential for non-contact in-situ inspection of rotor blade leading edges. Thermographic investigations on curved and coated GFRP specimens have shown that sub-surface defects not only represent a susceptibility to erosion, but that the onset of erosion is dependent on the depth of the defects. Furthermore, the damage development of sub-surface towards surface defects can be visualized, which allows the damage stage to be assigned to an erosion stage.

Automated summary

Defects such as voids in wind turbine blades affect premature rain erosion, particularly at the leading edge. Active thermography enables non-contact in-situ inspection of leading edges. Thermographic investigations reveal that sub-surface defects make the blades more susceptible to erosion, and erosion onset depends on defect depth. The development from sub-surface to surface defects can be visualized, allowing damage stage to be assigned to an erosion stage.