多自由度主系统多模态动力吸振的优化设计

针对多自由度系统的多模态控制，通过附加多个动力吸振器，利用有限子结构导纳功率流理论，以输入系统的净功率流在整个吸振频带内的总声功率级为控制量，对多个吸振器进行单独优化设计和联合优化设计。结果表明，即使相邻固有频率的比值大于2(也即可以认为两个模态不相互影响)，联合优化设计的效果也明显优于单独优化设计。

Optimum Design of DVA in the Multi-Degrees-of-Freedom System

The optimum design of the dynamic vibration absorber(DVA)is investigated to reduce the vibration of a multi-degrees-of-freedom system.On the basis of the theory of substructure mobility power flow,an equivalent admittance matrix and the power flows input to the major structure are deduced.Furthermore,regarding the net power flow input to the main vibration system as controlled object,discussed profoundly are the multiple modes control of multiple-degrees-of-freedom system with several absorbers attached.The parameters of the absorbers are optimized by using two approaches.One is to find the optimum parameters of each absorber in frequency domain and the other is to find simultaneously the optimum parameters of all absorbers.Even for the case that the rate of the neighboring modal frequencies is larger than 2,the effect of the DVA designed by the latter way is better than that by the former.So the latter approach,named as Combined Optimum Design Approach,is recommended when controlling the multiple modes of multiple-degrees-of-freedom system by using several absorbers,whatever the composition of the multiple resonance frequencies.