Modeling vibrational behaviour of non-smooth large scale dynamical systems

模拟非光滑大型动力系统的振动行为

• 批准号: RGPIN-2015-03650
• 负责人: Yu, Shudong
• 金额: $ 1.6万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=638631
• 关键词: Modeling; vibrational; behaviour; non; smooth

Large-scale dynamical systems (LSDS) exist in every industry and in virtually every aspect of science and engineering. An LSDS consists of inter-connected sub-systems or components, transferring loads, energy and heat through interfaces, and more importantly interacting with each other through surface-to-surface frictional contact in a non-smooth manner. A mechanical system, used in manufacturing and other industries, has many components connected together by joints to complete various sophisticated tasks. During operations, each topologically complex component experiences elasto-rigid motion. As a result, a large number of degrees of freedom (DOF's) are required to describe time-varying configurations of all components with sufficient accuracy. Non-smooth LSDS can respond violently to disturbances and excitations in a deterministic or even chaotic manner, and can cause poor machine precision, excessive noise, accelerated component wear, etc. As examples of non-smooth large scale LSDS, vibration of a CANDU nuclear fuel string, excited by pulsating coolant flow, has caused severe wear damage to the pressure tube and fuel bundle component failure in the Canadian nuclear industry; a high-speed machine having flexible links and joints can lose its stability when operated near a critical speed; motion of a vibrating machine with gap-activated springs can become chaotic at certain operating points, which result in poor system performance. Study of vibration of non-smooth LSDS is of ultimate importance to both system design and maintenance engineers.

大型动力系统 (LSDS) 存在于每个行业以及科学和工程的几乎每个方面。 LSDS由相互连接的子系统或组件组成，通过界面传递载荷、能量和热量，更重要的是通过表面到表面的摩擦接触以非光滑的方式相互作用。用于制造业和其他行业的机械系统具有许多通过关节连接在一起的组件来完成各种复杂的任务。在操作过程中，每个拓扑复杂的组件都会经历弹性刚体运动。因此，需要大量的自由度 (DOF) 来以足够的精度描述所有组件的时变配置。非光滑 LSDS 会以确定性甚至混沌的方式对扰动和激励做出剧烈响应，并可能导致机器精度差、噪声过大、部件加速磨损等。作为非光滑大规模 LSDS 的例子，CANDU 核的振动由脉动冷却剂流激发的燃料管柱已对加拿大核工业中的压力管造成严重磨损，并导致燃料管束组件失效；具有柔性连杆和接头的高速机器在接近临界速度时会失去稳定性；具有间隙激活弹簧的振动机的运动在某些操作点可能会变得混乱，从而导致系统性能不佳。非光滑 LSDS 振动的研究对于系统设计和维护工程师都至关重要。