复杂环境下旋转细长复合材料结构振动特性及稳定性

Rotating slender composite structures have been widely used in various fields including aerospace, energy and machinery, as turbine blades, helicopter rotor and fan blade, to name a few. According to previous studies on rotation blades, a rotation motion will induce various modes of vibrations, such as flapwise, lagwise, twisting and longitudinal forms (FLTL). These modes are generally coupled with each other. In specific, the intensity of vibration is closely related to rotational velocity. In some critical cases, instability would occur due to the rotation. According to the literature surveying on turbine blades, the influence of single factor of temperature, aero dynamic force，humidity and rotation on the intrinsic characteristics (natural frequency, mode, loss factor) and stability of vibrations coupled with FLTL in a rotation slender composite structure is beyond the scope of the previous studies, not to mention the effect of two or three of these factors. This project aims to investigate the characteristics of coupled vibration, stabilities of motion, and attractors of dynamical systems for a rotating slender composite structure that can be simplified as rotating composite beam in a complex environment. The governing equations characterizing the effect of temperature, humidity, aeroforce and rotation will be established. The characteristics and stability of coupled vibrations of such a structure will be investigated by using a nonlinear dynamic method. The mechanism of various damping behavious will be investigated. The geometric and topological sturcture and classfication of attractors of a corresponding system will be discussed. Formation and evolution of the associated attractors will be revealed. Achievement can be expected in modeling for rotating slender composite structures, analyses on characteristics of coupled vibration and stabilities, mathematical description and classification for attractors by considering effects due to temperature, humidity, aeroforce and rotation.

旋转细长复合材料结构在航空航天、能源、机械等领域被广泛应用，涡轮叶片、直升机旋翼、风机叶片等都是重要应用实例。前人针对旋转涡轮叶片的研究表明旋转将诱发产生舞、摆、扭、纵多种形式振动，这些振动相互耦合，不仅振动强度及稳定性与转速密切相关，而且可能导致运动失稳。目前少见气动力、湿热、旋转二者或三者联合作用下，旋转细长复合材料结构耦合（舞-摆-扭-纵）振动特性（固有频率、模态、损耗因子等）与稳定性的研究。本项目拟将旋转细长复合材料结构简化为旋转复合材料梁，建立其在湿热、气动力、旋转联合作用下耦合振动方程，用非线性动力学方法研究其耦合振动特性与稳定性特征、多阻尼联合作用机理，探讨该类系统吸引子几何和拓扑结构的数学描述和分类，揭示该类系统吸引子形成过程和演变规律。预计项目将在考虑湿热、气动、旋转联合作用下，旋转复合材料梁动力学建模、耦合振动特性和稳定性分析、吸引子结构描述和分类等方面取得创新成果。

旋转细长复合材料结构在航空航天、能源、机械等领域被广泛应用。前人针对旋转涡轮叶片的研究表明旋转将诱发产生舞、摆、扭、纵多种形式振动，这些振动相互耦合，不仅振动强度及稳定性与转速密切相关，而且可能导致运动失稳。目前少见气动力、湿热、旋转二者或三者联合作用下，旋转细长复合材料结构耦合（舞-摆-扭-纵）振动特性（固有频率、模态、损耗因子等）与稳定性的研究。. 本项目以复合材料风机叶片为工程背景，通过建立其在湿热、气动力、旋转联合作用下该类结构的耦合非线性振动方程，用非线性动力学理论和方法研究在旋转效应（定轴转动）、气动力效应、湿热效应联合作用下复合材料细长梁的振动特性与稳定性。得到了湿热效应、定轴转动效应、气动力效应对做定轴转动复合材料细长结构结构振动特性及稳定性的联合影响机理；给出了了设计参数如安装角、锥角、材料铺层角等对该类细长结构振动特性及稳定性的影响规律；对该类系统的非线性动力学问题，如参数振动、参数与强迫联合振动如进行了探讨。. 在该项目支持下，已公开发表学术论文28篇，其中SCI论文24篇，总计引用已超过150次（基于Cnki和Google学术查询）。参与了国内外学术交流40余人次，报告论文30余篇，其中参加国际会议8人次，报告国际会议论文6篇。已培养硕士生6人、博士生5人，3人获得四川省振动工程学会优秀论文奖。. 本项目将对做定轴转动的复合材料细长结构（如风力机叶片、直升机旋翼等），在多因素联合作用下的动力学建模，分析方法提供设计指导。