五体船运动非线性特性检验方法

采用替代数据法研究了五体船在随机海浪中运动响应系统性质的判别问题. 针对3种侧体排水量比例的五体船型在不同海况、浪向下的运动响应时历，运用改进傅里叶变换算法生成替代数据，计算检验统计量的判别指标，在显著水平为005下，对五体船运动响应系统性质进行了判别. 结果表明：五体船在随机海浪中的运动响应表现为线性系统特征，前后侧体的增加未改变五体船运动响应系统的性质，替代数据检验法能够准确合理地判定五体船运动响应系统的特性.

Testing Method Study of Nonlinearity Characteristic for Pentamaran’s Motion in Waves

The nature of pentamaran’s motion time series in waves was studied by surrogate data method.The motion response of three types of pentamarans in different sea state was predicted theoretically and the surrogate data were generated by the modified Fourier transform.At 0.05 significant levels,the nature of pentamaran’s motion time series was identified based on the testing statistics.The results indicate that the nature of motion response system does not change while four sponsons are arranged at the front and after side of the main hull body,and the surrogate data method can distinguish the system nature of pentamaran’s motion in random waves and also be fit for the identification of motion and wave load response system of ship and offshore structures.