基于有限元方法主轴箱振动的网格敏感性分析

Mesh sensitivity analysis of vibration in spindle box based on finite element method

为研究主轴箱的振动特性,采用基于有限元方法的COSMOS软件对绕线机的主轴箱进行模态分析,模拟了主轴箱前10阶固有频率和对应的振动模态。分析了网格精度对振动模态分析结果的影响,最粗网格的体积约为最细网格的43倍。网格精度对前5阶共振频率的影响较小,对后5阶共振频率的影响较为明显,最大误差达5.7%;在对精度要求不高的情况下,采用系统默认的网格精度可满足模态分析要求,基准误差中的最大误差不超过2.6%。

In order to investigate the vibration characteristics of the spindle box in a coiling machine, the software named COSMOS which is based on finite element method is adopted to simulate the resonant vibrations of the first 10 orders. The effects of the mesh resolution on numerical results are explored. The largest grid size is about 34 times larger than that of the smallest one. The mesh resolution gives minor contributions in the first 5 orders resonant frequencies, whereas affects obviously the last 5 orders resonant frequencies, showing a maximum error ratio of 5.7 %. In the circumstance which precision is not strictly limited, the default mesh resolution is satisfied to the vibration analysis, showing an error ratio of 2.6% in the base error.