双模态耦合系统的振动耗能特性研究

Theoretical Study of Vibration Energy Loss in Two-Coupled Mode System

以固有频率处于 1 /3倍频程内的一个双振子耦合系统为例 ,研究了双模态耦合系统的振动耗能特性。通过分别改变激励外力的频率和幅度、振子的基本特性、耦合元素特性等诸要素 ,对系统损耗因子进行了分析。研究发现 :耦合系统的损耗因子总是介于两个模态损耗因子之间 ,并且这两个模态一个从振动能量的角度占主导地位 ,而另一个从能量损耗的角度占主导地位 。

When the two resonance frequencies of two coupled mode system are low and in the same 1/3 Oct band, existing engineering methods fail to give a satisfactory estimate of energy loss. Our theoretical study aims to make a good estimate possible. We took a two coupled oscillator system, shown in Fig.1, as an example. Eqs. (3) and (4) are well known. Our theoretical study led to eqs. (5) and (6), which, we believe, will be helpful to making a good estimate of vibration energy loss when the two resonance frequencies are low and in the same 1/3 Oct band. Using eqs. (5) and (6), and selecting values for parameters m 1, m 2, k 1, k 2, k 3, c 1, c 2, c 3, F 1 and F 2 , we obtained Figs. 2 through 7, which show at a glance, the influence of parameters on vibration energy loss.