浮筏隔振系统的非共振响应分析

建立了筏架和基础板均为弹性体的浮筏动力学方程,分析了隔振器的非线性刚度对系统动态特性的影响。在线性条件下,通过刚柔耦合软件仿真,验证了建模理论的合理性,并通过功率流方法,对结构能量的传递进行了分析。在非线性条件下,隔振器具有立方非线性的刚度项,利用多尺度法研究系统发生内共振等条件,同时通过数值方法计算分析了系统在单频和多频激励下的非共振响应。研究结果表明:线性和非线性条件下的柔性浮筏隔振系统,其动力学特性区别明显。非线性条件下,筏架的刚柔程度显著地影响系统特性,而线性条件下的低频段,该影响较小。同时非线性条件下的系统存在较为复杂的谐波及倍周期现象。

The Non-resonant Response Research on Flexible Floating Raft Isolation System

Ship floating raft isolation system is an important technology approach which is used to improve the acoustic stealth performance of warships. The influence of raft frame and infrastructure flexibility and the nonlinear isolation is taken into account on the dynamic equations. In the linear condition, the CMD(Calculation of Multi-body Dynamics) software is used to confirm the reasonable of modeling method, and the transmission of vibration energy is researched by the power flow. In the nonlinear condition, method of multiple scales is used to research the dynamic response under the non-resonant state and the numerical solution is used to analyze the differential equation system. The result indicates that the dynamic character of rigid and the flexible raft frame are different in the nonlinear condition. The resonance response could be caused by the harmonic component in the non-resonant frequency.