摘要
Wepresentastudyofthenonlinearcouplinginternalresonancefortheheaverollandpitchperformanceofasparplatformunderthewaveandvortex-inducedloadswhentheratioofthefrequenciesofheave,rollandpitchareapproximately2:1:1.Inconsiderationofvaryingwetsurface,thethreeDOFsnonlinearcoupledequationsareestablishedforthesparplatformundertheeffectofthefirst-orderwaveloadsintheheaveandpitch,andvortexinducedloadsintheroll.Byutilizingthemethodofmulti-scaleswhenthevortex-inducedfrequencyisclosetothenaturalrollfrequency,thefirst-orderperturbationsolutionisobtainedanalyticallyandfurthervalidatedbythenumericalintegration.Sensitivityanalysisisperformedtounderstandtheinfluenceofthedampingandtheinternaldetuningparameter.Twocaseswithinternalresonanceareshown.Thefirstcaseisthatnosaturationphenomenonexistsundersmallvortex-inducedloads.Thefirstorderperturbationsolutionillustratesthatonlythevortex-inducedfrequencymotioninrollandthesuper-harmonicfrequencymotioninheaveareexcited.Thesecondcaseisthatthevortex-inducedloadsarelargeenoughtoexcitethepitchandasaturationphenomenonintheheavemodefollows.Theresultsshowthatthereisnosteadyresponseoccurrenceforsomecases.Forthesecaseschaosoccursandlargeamplitudesresponsecanbeinducedbythevortex-inducedexcitation.
出版日期
2017年04月14日(中国Betway体育网页登陆平台首次上网日期,不代表论文的发表时间)