【作者】 陈耀东；

【导师】 王维；

【作者基本信息】 沈阳航空工业学院 ， 机械设计及理论， 2008， 硕士

【摘要】 本论文针对飞机液压油车液压管路振动问题进行了分析,并对与此相关的管道振动基础理论进行了研究。液压油车振动的原因主要是机械振动和流体脉动引起的振动。因而对脉动流作用下铰支—铰支边界条件下的管道稳定性及全局分岔问题进行了深入研究。分析了飞机地面液压油车因振动带来的负面影响和在液压管路振动方面的研究进展。根据飞机地面液压油车的原理及整车结构形式,分析了整车的振动情况,给出了消除机械振动的一些有效方法。导出了脉动流作用下管道振动微分方程,对微分方程进行了无量纲化,并对无量纲化方程进行了离散化,得到二阶状态微分方程。讨论了系统有一对零特征值的条件,应用陀螺系统的正规形推导方法通过一系列的变换得到了0∶1内共振时的分岔方程,再经过重度量得到了一个四维近似可积的哈密顿系统。根据模态间内共振、全局分岔、能量—相位准则以及纤维丛理论,研究了哈密顿共振情况下的Silnikov轨道的存在性,得到了这类系统存在Silnikov轨道的必要条件。更多还原

【Abstract】 The vibration of hydraulic pipe for aircraft ground hydraulic cart is analyzed in this paper, and the associated fundamental theory is studied. The analysis shows that the cause of vibration of the pipe is the vibration of mechine and the fluctuating flow conveying fliud, and hence, the stability and global bifurcations of pinned-pinned pipes that the flow velocity harmonically perturbed about a constant mean value are mainly examined.The effect of the vibration of the pipe on the hydraulic cart is analyzed, and the development of research on the vibration of the hydraulic pipe are introduced. According to the working principle and the mechanical structure of aircraft ground hydraulic cart, the source of vibration are analyzed, and some valid methods that can remove mechanical vibration are given.The equation of motion of the system is established, and the differential equation is reduced by dimensionless and discretization procedures. Then the conditions that the system has zero eigenvalue are discussed. Applying the normal form method of gyroscopic system, the bifurcational equation with 0:1 internal resonance is obtained. By a series of variable transformations, a near-integrable four-degree-of-freedom Hamiltonian system is obtained. Using the energy-phase criterion and the fiber clump theory, the necessary condition of the existence of Silnikov orbits is determined under Hamiltonian resonance.更多还原