平面铝板上的压电振动除冰方法

以平面铝板为对象,对压电振动除冰方法进行了理论与实验研究。使用有限元方法(FEM)分析了压电片(PZT)长度和厚度对所激发结构模态振动强度的影响。建立了冰层的二维受力模型,分析接触面上的切应力分布,为除冰模态的选取提供指导。结果表明,理想情况下当PZT长度约为某模态半波长的奇数倍时,对该模态的激发效果最好,此外压电片长度还受到结构表面应变分布的影响。在满足强度要求的前提下,压电片厚度应尽量小。结构与冰接触面上的最大切应力出现在结冰边缘部位,大小与结构表面的应变有关,在振动节线附近的切应力最小。实验获得了较好的验证结果,除冰功率约为36.5 W/m2,比电热除冰方法的功耗低1~2个量级。

Vibration de-icing method with piezoelectric actuators on flat aluminum plate

This work presents the analytic and experimental research of a kind of de-icing method with piezoelectric transducer as actuators. The whole work is conducted on a flat aluminum plate. The finite element method (FEM) is used to get the relationships between the length and thickness of piezoelectric ceramic transducer (PZT) and the vibration intensity of the modes being excited. Two-dimensional analytic model is derived for ice bonded to the plate. This model leads to the ability to predict the shear stress along the bond layer between ice and plate and gives guidance as to the choice of modes of vibration for de-icing. The results show that for a certain mode the maximum excitation will happen when the PZT length is an odd integer multiple of the half wavelength of that mode. Actually the length will be a little affected by the strain distribution on the surface of plate. The thickness of PZT should be thin as long as the strength requirements are met. The maximum shear stress on the bond layer concentrates on the edge of length direction, and the amplitude depends upon the strain on the surface of plate under the edge of ice. Generally, minimum shear stress is produced around the stagnation line of certain mode. These conclusions are verified by a set of de-icing experiments and the power consumption is about 36.5 W/m², which is lower than that of electro-thermal de-icing method by one to two orders of magnitude.