摘要
悬链线立管在顶部浮体的带动下,其动力响应会诱发其周围产生相对来流,而这种振荡来流将激励立管悬垂段产生"间歇性"的涡激振动。在海洋工程水池中对不同最大约化速度URmax、KC数组合下的振荡来流作用下的柔性立管进行模型试验研究,利用光纤应变片测量柔性立管模型的涡激振动响应。结合模态分析与小波分析对试验数据进行分析,观察到一种区别于定常来流下的涡激振动响应形式,即具有"振幅调制"及"模态转换"的"分时特性"的涡激振动。最后讨论并总结了最大约化速度URmax以及KC数对涡激振动"分时特性"的影响规律。
Due to top vessel motions,dynamic responses of catenary risers induce relatively oscillatory flow around themselves.Such oscillatory flow easily triggers the sag-bend part of a riser to have intermittent VIVs.Here,tests for the behaviors of a flexible cylinder in oscillatory flow were conducted with different combinations of the maximum reduced velocity URmax and KC number.Fiber brag grating （FBG）strain sensors were used to measure the VIV response of the cylinder model.Then,modal analysis and wavelet analysis were adopted to deal with the experimental data,and the VIV response featured of “time sharing ” including amplitude modulation and mode transition was observed, it was distinguished from the VIV response in steady flow.Finally,the effects of the maximum reduced velocity and KC number on “time sharing”of VIV in oscillatory flow were discussed and summarized.
出处
《振动与冲击》
EI
CSCD
北大核心
2014年第21期1-7,共7页
Journal of Vibration and Shock
基金
国家自然科学基金面上项目(51279101)
国际自然科学基金重点项目(51239007)
关键词
振幅调制
模态转换
模态分析
小波分析
振荡来流
涡激振动
amplitude modulation
mode transition
modal analysis
wavelet analysis
oscillatory flow
vortex-induced vibration （VIV）
