简介：Fortheglobalandstructuralfatiguestrengthanalysisofasemi-submersibleplatform,waveloadsunderdesigncon-ditionsarecalculatedbyuseofthethree-dimensionalboundarydementmethod.Methodsforcalculatingtheforward-speedfree-surfaceGreenfunctionarediscussedandacomputerprogramwiththisGreenfunctionisdeveloped.Accordingtothespecialrules,thewaveloadsunderseveraltypicaldesignconditionsoftheplatformarecalculated.Themaximumverticalbendingmoment,torsionmomentandhorizontalsplitforcearedeterminedfromaseriesofcontourmapsofwaveloadsforthewaveperiodof5to18secondsatacertainintervalandthewavephaseofO°to360°atacertaininterval.Thewaveheightisdeterminedbythefunctionofwaveperiodwithagivenexceedanceprobability.Themaximumwaveloadsunderthecombinationofwaveparametersareusedastheinputofhydrodynamicpressureinthethree-dimensionalfiniteelementanalysisprocess.Thetransferfunctionsofwaveloadsontheplatformareusedforthefatiguestrengthanal-ysisoftheK-tubularjointandthesub-modelofthestructure.

简介：—Thepresentstudyinvestigatestheinteractionofsteepwaveswithsemi-circularbreakwaterwiththecomplexplane＇sCauchyboundaryintegraltheorem.Theboundaryintegralmethodisusedtotransformthecalculationinfluiddomainintoitsboundaryalone.Inthecalculationthecomputationdo-mainismovedwiththepropagationofwaves.AnumericalsolutionisobtainedforincidentStokeswavespassingthesubmergedobstacles.Thismethodhasbeenextendedtothecalculationofwaverun-uponaslopeforestimatingwaveovertopping.

简介：Inthispaper,anewdefinitionofstructuresystemredundancyisproposedinviewofthevariousmeasuresforstructureredundancy.Byintroducingthetermsofstructuresystemfailureatthemechanismlevelandequivalentreliabilityindex,thesafetyforexistingoffshoreplatformscanbeevaluatedbythesemi-probabilisticmethodpresentedinthispaper.Somenumericalexamplesaregivenandsatisfactoryresultshavebeenobtained.

简介：流动和海水汇率为回收并且挖出工作被安排的一个围住半的浅海湾用atwo维的数字模型和一个Lagrangian方法被预言了。流动和强调的材料运输过时的人或物上的风效果，和风的三十年的平均值在数字模拟被考虑了。总体上，甚至在回收并且挖出被进行以后，流动模式看起来类似于原来的国家。然而，直到20%～100%的速度变化出现在构造区域的附近。在强迫的夏天风的情况中，在回收并且挖出，，以后的从71.6%～82.9%的海水汇率增加由particle-trackingmethod显示了。在强迫的冬季风的情况中，相反，海水汇率看起来在自然条件下面是97.2%，但是在回收并且挖出以后稍微减少到93.2%。因此，强迫的风在控制海水汇率起一个重要作用。如果挖出同时与回收被执行，Theseawater汇率被15%进一步改进。这建议挖出的罐头是一个有效工具减轻流动的变化。

简介：—Theresultsofdesignandexperimentofasubmergedsemi-circularbreakwaterattheYangtzeestuaryshowthatthesubmergedstructurewillbeunsafewhenthegeneralempiricalwaveforceformulaforsemi-circularbreakwaterisusedindesign.Therefore,anewcalculationmethodforthewaveforcesact-ingonasubmergedsemi-circularstructureisgiveninthispaper,inwhichthewaveforceactingonthein-sidecircumferenceofsemi-circulararchisincluded,andthephasemodificationcoefficientinthegeneralempiricalformulaisadjustedaswell.Thenewwaveforcecalculationmethodhasbeenverifiedbythere-sultsofsevenrelatedphysicalmodeltestsandadoptedinthedesignofthesouthesturaryjettyofthefirststageprojectofDeepChannelImprovementProjectoftheYangtzeRiverEstuary,thetotaljettylengthbe-ing17.5km.

简介：TheMultipleColumnPlatform(MCP)semi-submersibleisanewlyproposedconcept,whichdiffersfromtheconventionalsemi-submersibles,featuringcentrecolumnandmiddlepontoon.Itisparamounttoensureitsstructuralreliabilityandsafeoperationatsea,andarigorousinvestigationisconductedtoexaminethehydrodynamicandstructuralperformanceforthenovelstructureconcept.Inthispaper,thenumericalandexperimentalstudiesonthehydrodynamicperformanceofMCPareperformed.Numericalsimulationsareconductedinboththefrequencyandtimedomainsbasedon3Dpotentialtheory.Thenumericalmodelsarevalidatedbyexperimentalmeasurementsobtainedfromextensivesetsofmodeltestsunderbothregularwaveandirregularwaveconditions.Moreover,acomparativestudyonMCPandtwoconventionalsemi-submersiblesarecarriedoutusingnumericalsimulation.Specifically,thehydrodynamiccharacteristics,includinghydrodynamiccoefficients,naturalperiodsandmotionresponseamplitudeoperators(RAOs),mooringlinetensionarefullyexamined.ThepresentstudyprovesthefeasibilityofthenovelMCPanddemonstratesthepotentialpossibilityofoptimizationinthefuturestudy.

简介：由于胭脂波浪的物理机制的复杂性，rogue-wavestructure相互作用问题的理论学习仍然取得很少进步。为常规形状的结构，然而，给理论分析是可能的，如果流氓波浪的一个相对简单的模型被使用。波浪负担，由作为胭脂波浪的一个直觉的基本模型被知道的一个集中的波浪导致了，在沉没半的柱体之上被学习经分解。集中的波浪由高斯信封波浪是近似的，包含流氓波浪的大多数特征的一个理想的模型。衍射速度潜力通过水平力量的流动地，和公式的分离被导出，弯曲时刻被建议。导出的公式适当地被简化，并且对数字结果通过比较验证了。另外，参数的影响集中的沉没深度和波浪例如集中的度，放，彻底地被调查。

简介：这份报纸地址关节风波浪导致了在正常状态和差错事件下面的近海的漂浮风汽轮机(OFWT)调节的一种半类型的动态回答。在这份报纸的分析及时被进行领域，用aero-hydro-servo-elastic模拟代码--快。由于唯一粘滞参考书系统的特征，实现在的原来的粘滞的抑制模型快被二次的代替获得精确俘获粘滞效果。模拟盒子在静止的水里包含免费腐烂的运动，面对常规波浪稳定运动并且象处于有或没有风的运作的海状态的动态反应一样弯屈。模拟也包括盒子因为快片在紧急情况以后投球导致的短暂回答关机。在许多刺激下面的站台运动，本地结构的负担和典型绳索行紧张力量的特征被获得并且调查。

简介：

简介：Adesignofsemi-submersibleplatformismainlybasedontheextremeresponseanalysisduetotheforcesexperiencedbythecomponentsduringlifetime.Theexternalloadscaninducetheextremeairgapresponseandpotentialdeckimpacttothesemi-submersibleplatform.Itisimportanttopredictairgapresponseofplatformsaccuratelyinordertocheckthestrengthoflocalstructureswhichwithstandthewaveslammingduetonegativeairgap.Thewindloadcannotbesimulatedeasilybymodeltestintowingtankwhereasitcanbesimulatedaccuratelyinwindtunneltest.Furthermore,fullscalesimulationofthemooringsysteminmodeltestisstillatuffworkespeciallythestiffnessofthemooringsystem.Owingtotheabovementionedproblem,themodeltestresultsarenotaccurateenoughforairgapevaluation.Theaimofthispaperistopresentsensitivityanalysisresultsofairgapmotionwithrespecttothemooringsystemandwindloadforthedesignofsemi-submersibleplatform.Thoughthemodeltestresultsarenotsuitableforthedirectevaluationofairgap,theycanbeusedasagoodbasisfortuningtheradiationdampingandviscousdraginnumericalsimulation.Inthepresenteddesignexample,anumericalmodelistunedandvalidatedbyANSYSAQWAbasedonthemodeltestresultswithasimple4linesymmetricalhorizontalsoftmooringsystem.Accordingtothetunednumericalmodel,sensitivityanalysisstudiesofairgapmotionwithrespecttothemooringsystemandwindloadareperformedintimedomain.Threemooringsystemsandfivesimulationcasesaboutthepresentedplatformaresimulatedbasedontheresultsofwindtunneltestsandsea-keepingtests.Thesensitivityanalysisresultsarevaluableforthefloatingplatformdesign.

简介：Afullycoupled6-degree-of-freedomnonlineardynamicmodelispresentedtoanalyzethedynamicresponseofasemi-submersibleplatformwhichisequippedwiththedynamicpositioning(DP)system.Inthecontrolforcedesign,adynamicmodelofreferencelineardriftfrequencyinthehorizontalplaneisintroduced.Thedynamicsurfacecontrol(DSC)isusedtodesignacontrolstrategyfortheDP.Comparedwiththetraditionalback-steppingmethods,thedynamicsurfacecontrolcombinedwithradialbasisfunction(RBF)neuralnetworks(NNs)canavoiddifferentiatingintermediatevariablesrepeatedlyineverydesignstepduetotheintroductionofafirstorderfilter.LowfrequencymotionsobtainedfromtotalmotionsbyalowpassfilterarechosentobetheinputsfortheRBFNNswhichareusedtoapproximatethelowfrequencywaveforce.Consideringthepropellers’wearandtear,theeffectoffilteringfrequenciesforthecontrolforceisdiscussed.Basedonpowerconsumptionsandpositioningrequirements,theNNcentersaredetermined.Moreover,theRBFNNsusedtoapproximatethetotalwaveforcearebuilttomonitorthedisturbances.WiththeDPassistance,theresultsoffullycoupleddynamicresponsesimulationsaregiventoillustratetheeffectivenessoftheproposedcontrolstrategy.