For estimating the vibration transmission accurately and performing vibration control efficiently in isolation systems, a novel general model is presented to predict the power flow transmitted into the complicate flex...For estimating the vibration transmission accurately and performing vibration control efficiently in isolation systems, a novel general model is presented to predict the power flow transmitted into the complicate flexible bases of laminated beams. In the model, the laminated beam bases are simulated by the first-order shear deformation laminated plate theory, which is relatively simple and economic but accurate in predicting the vibration solutions of flexible isolation systems with laminated beam bases in comparison with classical laminated beam theories and higher order theories. On the basis of the presented model, substructure technique and variational principle are employed to obtain the governing equation of the isolation system and the power flow solution. Then, the vibration characteristics of the flexible isolation systems with laminated bases are investigated. Several numerical examples are given to show the validity and efficiency of the presented model. It is concluded that the presented model is the extension of the classical one and it can obtain more accurate power flow solutions.展开更多
A new concept, namely, the equivalent mobility matrix of coupling subsystem is proposed, and the corresponding threesubsystem coupling progressive approach is explored. With the new efficient approach presented, the c...A new concept, namely, the equivalent mobility matrix of coupling subsystem is proposed, and the corresponding threesubsystem coupling progressive approach is explored. With the new efficient approach presented, the complexity in dealing with a more complicated dynamic coupling system is greatly reduced. The new modeling method is then combined with the theory of power flow to investigate the dynamics of the overall non rigid isolation system from the viewpoint of energy. The interaction between the resilient machine of its main modes and the resonant behavior of the flexible foundation on power flow transmission is studied. Taking a machine tool mounted on a multi story working plant as an example, the dynamic characteristics of the machine foundation coupling system are analyzed, and their effects on power flow transmission are revealed under various service frequency bands. Some advisable control strategies and the design principle for machinery mounted on flexible structure are proposed.展开更多
In this paper we present the effect of vibration source on the power flow transmission in a compound flexible system. Considering the internal impedance of the source, a general model is here proposed, and the general...In this paper we present the effect of vibration source on the power flow transmission in a compound flexible system. Considering the internal impedance of the source, a general model is here proposed, and the generalized transfer equations of the system and the closed form solutions for power flow in the fiexible system are then developed, with which the effects of the source characteristics on power flow transmission are discussed. The investigation shows that when the source and receiver impedances are comparable, substantial error can occur in the power flow estimation if the source is assumed to be an ideal constant force source (CFS)or a constant velocity source (CVS).展开更多
现代机械的高速化和轻量化的发展趋势导致了更加严重的振动噪声问题,因此柔性系统的高频隔振降噪是机械设计过程中必须要考虑的问题。充分考虑机械系统的柔性性质,采用子结构导纳综合法和传递矩阵技术,建立多激励多支承的柔性机器和柔...现代机械的高速化和轻量化的发展趋势导致了更加严重的振动噪声问题,因此柔性系统的高频隔振降噪是机械设计过程中必须要考虑的问题。充分考虑机械系统的柔性性质,采用子结构导纳综合法和传递矩阵技术,建立多激励多支承的柔性机器和柔性基础(Flexible machine and flexible base,FMFB)全柔性隔振系统的一般动力学模型和力学描述,该模型不但包含了刚性机器和刚性基础(Rigid machine and rigid base,RMRB)、刚性机器和柔性基础(Rigid machine and flexible base,RMFB)、柔性机器和刚性基础(Flexible machine and rigid base,FMRB)等多种隔振模型,而且还可以借助该模型分析积极隔振和被动隔振等问题。通过系统综合,给出适合于不同隔振系统的传递率和功率流表达式,探讨各类柔性系统的固有频率耦合规律,并研究它们的振动传递特性等问题,得到了一些有价值的结论,对柔性隔振设计具有重要的指导意义。展开更多
基金supported by National Natural Science Foundation of China (Grant No. 50805088)China Postdoctoral Science Foundation (No.2004035223)
文摘For estimating the vibration transmission accurately and performing vibration control efficiently in isolation systems, a novel general model is presented to predict the power flow transmitted into the complicate flexible bases of laminated beams. In the model, the laminated beam bases are simulated by the first-order shear deformation laminated plate theory, which is relatively simple and economic but accurate in predicting the vibration solutions of flexible isolation systems with laminated beam bases in comparison with classical laminated beam theories and higher order theories. On the basis of the presented model, substructure technique and variational principle are employed to obtain the governing equation of the isolation system and the power flow solution. Then, the vibration characteristics of the flexible isolation systems with laminated bases are investigated. Several numerical examples are given to show the validity and efficiency of the presented model. It is concluded that the presented model is the extension of the classical one and it can obtain more accurate power flow solutions.
文摘A new concept, namely, the equivalent mobility matrix of coupling subsystem is proposed, and the corresponding threesubsystem coupling progressive approach is explored. With the new efficient approach presented, the complexity in dealing with a more complicated dynamic coupling system is greatly reduced. The new modeling method is then combined with the theory of power flow to investigate the dynamics of the overall non rigid isolation system from the viewpoint of energy. The interaction between the resilient machine of its main modes and the resonant behavior of the flexible foundation on power flow transmission is studied. Taking a machine tool mounted on a multi story working plant as an example, the dynamic characteristics of the machine foundation coupling system are analyzed, and their effects on power flow transmission are revealed under various service frequency bands. Some advisable control strategies and the design principle for machinery mounted on flexible structure are proposed.
文摘In this paper we present the effect of vibration source on the power flow transmission in a compound flexible system. Considering the internal impedance of the source, a general model is here proposed, and the generalized transfer equations of the system and the closed form solutions for power flow in the fiexible system are then developed, with which the effects of the source characteristics on power flow transmission are discussed. The investigation shows that when the source and receiver impedances are comparable, substantial error can occur in the power flow estimation if the source is assumed to be an ideal constant force source (CFS)or a constant velocity source (CVS).
文摘现代机械的高速化和轻量化的发展趋势导致了更加严重的振动噪声问题,因此柔性系统的高频隔振降噪是机械设计过程中必须要考虑的问题。充分考虑机械系统的柔性性质,采用子结构导纳综合法和传递矩阵技术,建立多激励多支承的柔性机器和柔性基础(Flexible machine and flexible base,FMFB)全柔性隔振系统的一般动力学模型和力学描述,该模型不但包含了刚性机器和刚性基础(Rigid machine and rigid base,RMRB)、刚性机器和柔性基础(Rigid machine and flexible base,RMFB)、柔性机器和刚性基础(Flexible machine and rigid base,FMRB)等多种隔振模型,而且还可以借助该模型分析积极隔振和被动隔振等问题。通过系统综合,给出适合于不同隔振系统的传递率和功率流表达式,探讨各类柔性系统的固有频率耦合规律,并研究它们的振动传递特性等问题,得到了一些有价值的结论,对柔性隔振设计具有重要的指导意义。