全柔性隔振系统功率流的有限元计算及其传递特性研究

Finite Element Calculation and Transfer Characteristics Analysis of Power Flow for Fully Flexible Isolation Systems

传统隔振模型中设备甚至基础被视为绝对刚性,隔振器被视为质量弹簧,无法计及基础和设备柔性以及隔振器质量等对振动传递的影响。另外,基于传统模型计算传递功率流时,需要假设设备和基础形状规则以方便获得其导纳解析式。以不规则板模拟柔性设备和基础,以空间阻尼梁替代弹簧或隔振器,建立全新的全柔性隔振系统模型。采用有限元方法将整个系统离散,计算隔振器和板耦合节点处的力和速度,从而给出了输入系统和传递至基础的功率流的表达式。研究全柔性隔振系统功率流的传递特性,对建立目前机械设备发展所需的隔振系统模型具有指导意义。

In the traditional vibration isolation model,the equipment and foundation are treated as absolute rigid bodies,and the isolators are modeled as massless springs.Such a model cannot deal with the influence of equipment’s and foundation’s flexibilities and isolator’s mass on the vibration energy transmission.In addition,the shapes of the equipment and foundation need to be greatly simplified to obtain the analytical solution of mobility.In this paper,a model of the fully flexible isolation system is established,in which the equipment and foundation are considered as arbitrarily shaped plates and the isolator is simplified as a spatial beam respectively.The isolation system is discretized,and the velocities and forces at coupled nodes are computed by means of finite element analysis.Then,the expression of the power flow from the equipment to the foundation is formulated.The transfer characteristics of the fully flexible system are investigated.Some valuable conclusions are obtained,which are of some significance to build up vibration isolation models for mechanical equipment.