Abstract: In order to prevent the harms caused by too large ship shafting vibrations when the performances of vibration dampers declined during the  ship moving，an algorithm of analysis and extraction of the phase angles  of ship shafting vibration dampers in frequency domain was proposed herein,a twist vibration meter  was used to constantly measure and compute the  inner and outer angular velocities of vibration dampers，the phase angles  and damping coefficients of the vibration damper were obtained and error  reasons were analyzed，large error data were excluded ，then the fitted  curves were compared with standard curves to estimate the performances of  vibration dampers.The prototype test results show that the algorithm may  accurately calculate the phase angles of the vibration dampers，and the  fitted curves are of high accuracy，which satisfy the design requirements  on ship shafting performances of vibration dampers.

Key words: ship shafting, vibration damper, phase angle, damping coefficient, frequency domain analysis

摘要： 为了预防船舶行进过程中减振器性能衰退引起轴系振动过大所带来的危害，提出了船舶轴系减振器相位角频域分析提取算法，使用扭振仪对减振器内外圈扭角速度 进行实时测量，计算减振器的相位角和阻尼系数，分析误差原因，筛除误差较大的数据，将拟合曲线与标准曲线进行对比，判断减振器性能。实船测试结果表明，该算法能准确计算出减振器相位角，拟合曲线精确度高，满足了船舶轴系减振器性能分析的设计要求。

关键词: 船舶轴系, 减振器, 相位角, 阻尼系数, 频域分析