Nonlinear Dynamic Analysis Of Multi-supported Vibration Isolation System On Flexible Foundation

For applications in engineering practice, the structure vibration and noise is the project important engineering problem effectively in the field of forecast and control to be considered.Flexible foundation structures has been widely used in recent years, such as aircraft, ships, construction and medical apparatus and instruments and other fields.With flexible structure prone to vibration problems in use,it affects the work of equipment performance and safety performance,making the problem of vibration isolation system based on tender basis of dynamic coupling vibration gradually become the hot topics in the study of many scholars.With the theory vibration isolation of flexible foundation and the development and application of nonlinear vibration isolator technology, the main feature of this work is that the dynamics modeling of nonlinear isolation system of multi-support on flexible foundation is established. the effect of vibration isolation is evaluated through vibration power flow theory. and the numerical solution and the simulation of system dynamics equation and other issues are discussed in this paper, the system parameters impacting on the steady state motion characteristics and power flow transmission characteristics is analyzed. Work presented in this paper can provide the beneficial reference for optimization of the nonlinear vibration isolation system in the engineering practice.First, the components of vibration isolation using general nonlinear constitutive equation, simply supported beam simulates the elastic foundation of installation. The dynamics model of nonlinear vibration isolation system supported on flexible foundation is established. The equation of system dynamics is deduced, The dynamics model of nonlinear vibration isolation system is analyzed by power flow theory. Considering diversity of nonlinear constitutive equation of isolation system, several nonlinear vibration isolator and its mechanical characteristic has carried on the summary.Secondly, on the basis of system dynamics model, the system dynamic equation is transformed into state space equation of dimensionless form through the vibration modal superposition method, the properties of orthogonal functions and the dimensionless processing. Further based on Runge-Kutta method, the system simulation model is established under matlab environment, the numerical method is discussed, which solves the system model of the compiling principle of calculation software.Finally, the system are analyzed in numerical simulation, which is consist of internal combustion engine of HS-700and air spring vibration isolator and elastic installation, two big plate are divided:first, through the theory of phase diagrams and poincare mapping, the engine displacement and angular displacement and the steady state motion characteristics of the flexible foundation are analyzed. At the same time, from the perspective of the computing efficiency of the numerical simulation, the simulation time need to be discussed; second, from view of Amplitude frequency characteristics and vibration power flow, the vibration isolator stiffness, damping, engine support layout parameters, the foundation elasticity are analyzed, which affect the system.