圆孔对等厚薄圆板固有频率影响的研究

首先由MARC软件对无孔与有孔的两个等厚薄圆板试件进行了模态分析，得出了前四阶固有频率的大致范围，根据该值确定实验中截止频率的取值；用敲击法测量了两试件的固有频率，并根据实验结果确定了有限元分析的单元类型与网格布局；最后采用该单元类型与网格布局对等厚薄圆板进行了系列计算，得出了圆孔大小、位置对薄圆板固有频率的影响规律，为挖孔减重提供科学的理论依据。

Research on the Effects of Round Hole to Natural Frequencyof Thin Round Plate

In this paper, modal analysis of two even thickness thin circular plate specimens, one with holes and the other without holes, are carried out with general finite element software Marc firstly. Approximate range of the prior four natural frequencies is acquired, based on which possible values of cut off frequencies in experiment are obtained. Natural frequencies of two specimens are obtained by hitting method, and the element types and grid distributions of finite element analysis are confirmed based, on the experimental results secondly. At last the effect law to natural frequencies that the size and place of circular holes is derived based on which a series of computation for the even thickness thin circular plate are carried out by adopting above mentioned element types and grid distributions, which provide scientific theoretical bases for weight reduction of hole digging.