Experimental Research and Simulation Analysis of Lightning Ablation Damage Characteristics of Megawatt Wind Turbine Blades

In this paper, the damage mechanism of glass fiber reinforced composite (GFRC) under lightning strike by laying and inserting copper wires in the laminate was studied. The ablation characteristics of GFRC under different lightning current components were explored. Scanning electron microscope (SEM) was used to conduct the morphology analysis at the damaged area. The results show that the high temperature induced by lightning striking leads to resin pyrolysis, glass fiber (GF) sublimation, and stress waves, which results in fiber breakage and delamination. Then, a finite element (FE) thermal-electric coupling model for predicting the lightning ablation damage of GFRC was established. The comparison between the simulation and experimental results are in good agreement, which validate the effectiveness of the proposed FE model. The relationship between the lightning ablation area and the lightning current amplitude, charge amount, and specific energy in creeping discharge and through discharge was obtained by data fitting. The whole ablation damage process was revealed by FE simulation.