Ultrasonic micro-vibration deicing of flat plate for wind turbine blades
LI Yan1,2*, DONG Xiaoyu1,GUO Wenfeng1,2, ZHANG Yingwei1,2
1. Engineering College of Northeast Agricultural University, Harbin, Heilongjiang 150030, China; 2. Heilongjiang Key Laboratory of Agricultural Renewable Resources Utilization Technology and Equipment in Cold Area, Harbin, Heilongjiang 150030, China
Abstract：The purpose of this research is to apply the micro-vibration generated by ultrasonic to de icing the blade. Because of the large wind turbine blade, the local blade can be approximately consi-dered as the flat plate. The simulation and experimental methods were used to carry out the research of ultrasonic deicing on the plate. First of all, the variations of first-order natural frequencies with thicknesses of ice layers are simulated and analyzed by ANSYS. The variations of the maximum shear stress, at the adhesive interface between the ice layer and the aluminum plate, with the thicknesses of ice layers and the excitation frequency are analyzed. Meanwhile, the effects of excitation voltage on the shear stress and the deicing area ratio are also researched. Based on the findings, an ultrasonic deicing experimental system is designed and fabricated. The adhesive forces of ice layers are measured with ultrasonic excitation. The findings show that, when the shear stresses at the adhesive interface are distributed uniformly, and the positive and negative shear stresses are alternatively distributed regularly, the deicing area ratio is the highest, which is suitable for ultrasonic vibration deicing. The experimental results show that the ultrasonic vibration can decrease the adhesive force of ice layer dramatically. The minimum adhesive force is only 23.7% of the one with no ultrasonic vibration. The findings can lay the theoretical and experimental foundations for the application of the ultrasonic micro-vibration technology to the wind turbine deicing.
