Stress Model Analysis and Effectiveness of an Ultrasonic Guided Wave De-icing Technique

Purpose: In order to solve the problem of ice accumulation on the surface of wind turbine blades, a two-dimensional stress analysis model, numerical simulation and experiment for ultrasonic de-icing were completed in this paper. Methods: 2-D stress analysis was used to illustrate the stress distribution of ice-covered structures under ultrasonic excitation. The stress analysis model shows that the maximum stress appears the edge of ice. The dispersion curves for substructure with ice were calculated to determine the suitable excitation frequency range and guided wave modes. Results: When the shear stresses generated are greater than the adhesive stress of the ice layer on the structure, the ice layer will break and fall off. The shear stresses generated by transducers at different installation distance between the two sandwich transducers were calculated to determine the installation distance and excitation frequency of transducers. The numerical simulation results and experimental results show that the ultrasonic guided waves de-icing is feasible. Conclusions: The simulation results are in good agreement with the experimental results and provide a good reference for experiments. The icing at the edge of plate will crack and de-bond first, and the icing at the sticking position of transducers crack and shed off lastly.