面外弯曲振动薄板上的除冰剪切应力分布特征研究

Distribution Characteristics of De⁃icing Shear Stress on Thin Plate with Out⁃of⁃Plane Flexural Vibration Mode

基于压电驱动器激励振动的机械力学式除冰技术是一种重量小和能耗低的新型除冰技术,用于应对航空结冰威胁问题。其中机械振动引起的界面剪切应力和相应结构振动模态是该除冰技术研究中的两个重要方面。寻找合适的振动模态来产生足够的界面剪切应力以提高除冰效率是研究中的重要内容。薄板的振动模态通常用横向轴线和纵向轴线上的反节点数m和n来描述。本文目的是研究不同结构弯曲振动模态下除冰剪切应力的分布特征,从而为基于机械振动的结冰防护系统(Ice protection system,IPS)的详细设计建立目标振动模态的选择依据。通过理论分析和仿真计算,建立了界面剪切应力与结构振动模态参数之间的关系。采用“冰层⁃平板⁃压电陶瓷”的有限元分析模型(Finite element model,FEM),仿真计算了不同振动模态下的应力应变水平,并根据仿真和实验结果分析了除冰剪切力的分布特征。最终给出了基于弯曲振动模态参数m和n的特征来确定除冰模态的选择标准。

Ice protection technology based on the mechanical vibration of piezoelectric actuators is a new lightweight and energy-efficient de-icing method.It is gaining increasing interest for use in aviation to mitigate ice-related hazards.The investigation of mechanical vibration de-icing technology encompasses two primary aspects:interface shear stress induced by mechanical vibration and corresponding vibration modes.Finding proper vibration modes to generate enough interface shear stress for de-icing efficiency improvement is a challenge.The vibration mode of the plate is often described by the values m and n,while m and n are the number of anti-nodes in the transversal axis and longitudinal axis separately.This paper is to investigate the distribution characteristics of de-icing shear stress and related vibration parameters(m and n)under different structural vibration modes,so as to establish the structure mode selection criteria for the detail designing process of the mechanical vibration-based ice protection system(IPS).The relationship between interface shear stress and vibration mode parameters under the single force excitation is established by theoretical analysis and simulation methods.A finite element model(FEM),depicting an aluminum plate with an ice layer attached to its surface,is used to simulate the stress-strain levels of the whole structure.According to the simulation outcomes and experimental verification,the distribution characteristics of de-icing parameters are analyzed.The selection of the initial de-icing modes based on the characteristics of m and n values of the flexural vibration modes is emphasized.