浮筏隔振装置的超单元建模方法

浮筏是一种集弹簧、阻尼器、刚体和弹性体为一体的混合动力学系统，对其建立合适的动力学模型存在困难，为此本文提出一种超单元建模方法。该方法首先在物理空间中对装置中弹性体的有限元模型进行降阶，并建立相应的超单元，然后与普通单元一样把它们直接组装到总体模型中。用该方法建立起来的动力学降价模型不仅在规模上远小于未降阶的有限元模型，而且能很好地保留原模型在中、低频段内的动态特性。数值示例表明，本文提出的超单元建模方法是一种有效的浮筏隔振装置建模方法。

A SUPERELEMENT METHOD FOR MODELING OF FLOAT RAFT ISOLATION SYSTEMS

A float raft is a kind of mixed dynamic system which includes springs, dampers, rigidand elastic structures. It is difficult to construct a reasonable dynamic model for it. A superelement method for the modeling of the system is proposed in this paper. In thismethod, the finite element models of the elastic structures in the system are reduced in thephysical space to formulate the corresponding superelements. Then the superelements areadded to the general model directly just like the common elements. The dynamic model obtained from the proposed method is much smaller than the full finite element model in dimension and can preserve all the dynamic characteristics in the low and middle frequencyrange of the full model. Numerical example shows that the proposed superelement modeling method is an efficient one for the float raft isolation systems.