为减小瑞利阻尼参数对浮筏动力特性分析精度的影响，根据试验测得的模态频率和模态阻尼比，利用加权最小二乘法计算瑞利阻尼系数，以使得各阶模态阻尼比相对误差的平方和最小，与常用方法相比，可得到更为满意的效果。参与加权最小二乘计算的模态阶数影响到模态阻尼比的相对误差，综合考虑模态参与因子和有效模态质量，确定了主自由度有效模态质量累计参与系数高于95% 的模态选取原则。依据该原则，将加权最小二乘法用于浮筏动力分析中瑞利阻尼系数的确定，根据该模态选取原则所确定的阻尼系数能满足浮筏动力特性工程计算的实际需要。
In order to reduce the influence of Rayleigh damping parameters on the calculation accuracy of floating raft dynamic characteristics, based on the experimental data of mode frequency and damping ratio, the method of weighted least square is used to calculate coefficient of rayleigh damping which can insure that the sum of square of relative error of mode damping ratio is smallest, we can get satisfying result compared with the common method. The number of mode which participate in calculation can effect the relative errors of mode damping ratio, combined with the method of mode analysis method based on effective mode mass and mode participation factor ,The mode selection principle is determined that accumulative effective mass participation factor ought to be bigger than 95% in the main freedom degree. The principle is used in determination of rayleigh damping coefficient for dynamic analysis of floating raft. the rayleigh damping coefficient determined by this principle can satisfy the need for dynamic analysis of floating raft in engineering.
2023,45(19): 55-59 收稿日期：2022-09-19
DOI：10.3404/j.issn.1672-7649.2023.19.010
分类号：TB535
基金项目：国防装备预研基金资助项目（41410030102）
作者简介：李海峰(1989-),男,博士,讲师,研究方向为旋转机械声场分析与测试
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