简介：本文介绍了一种近岸往复流同向推动涡轮发电设备，由进水通道、排水通道和横向通道组成，近岸海水的往复流动通过发电设备被转化为涡轮的单向旋转.同时，根据近岸往复流特点，分析了近岸海水流速、横流通道两端压差和输出功率关系，当近岸海水流速较小时，需要增加进水通道流通截面积；当近岸海水流速较高时，需要减小涡轮发电机转矩，提高发电设备输出功率.

简介：WedevelopedadetailedsimulationmodeloftheArcticmarinetransportsystem(MTS)foroilplatformPrirazlomnaya.Themodelhasamultidisciplinarynatureandinvolves:sub-modelsofvarioustransportandtechnologicalprocesses;stochasticweathergeneratortoobtaintimeseriesof15environmentalparameters;andcontextualplanningalgorithmtobuildvoyageplanconsideringseveraltypesofshipsandcargoes.Weusedasignificantamountofrealoperationaldatatoidentifymodelparametersandtoproveitsstatisticalreliability.Ourmainscientifictaskistoinvestigatetheinteractionofvariousprocessesofadifferentnature,whilethepracticalaimistofindasetofmeasurestoincreasetheefficiencyofMTS.Theresultsofthestudyrevealmanyexamplesofthemutualinteractionofvariousprocessesthatneedtobeconsideredatthedesignstagetoavoidtechnicalmistakes.ThestudyformedabasisformakingmanagerialdecisionsatthetoplevelofGazpromNeftShelfCompany.

简介：Acomplianttowerismodeledasapartiallydry,partiallytapered,dampedTimoshenkobeamwiththesuperstructuremodeledasaneccentrictipmass,andanon-classicaldampedboundaryatthebase.Thefoundationismodeledasacombinationofalinearspringandatorsionalspring,alongwithparallellinearandtorsionaldampers(Kelvin-Voigtmodel).Thesuperstructureaddstothekineticenergyofthesystemwithoutaffectingthepotentialenergy,therebyreducingthenaturalfrequencies.Theweightofthesuperstructureactsasanaxialcompressiveloadonthebeam,reducingitsnaturalfrequenciesfurther.Theemptyspacefactorduetothetruss-typestructureofthetowerisincluded.Theeffectofsheardeformationandrotaryinertiaareincludedinthevibrationanalysis;withthenon-uniformbeammode-shapesbeingaweightedsumoftheuniformbeammode-shapessatisfyingtheendcondition.TheweightsareevaluatedbytheRayleigh-Ritz(RR)method,andverifiedusingfiniteelementmethod(FEM).Theweightofthesuperstructureactsasanaxialcompressiveloadonthebeam.Kelvin-Voigtmodelofstructuraldampingisincluded.Apartofthestructurebeingunderwater,thevirtualaddedinertiaisincludedtocalculatethewetnaturalfrequencies.Aparametricstudyisdoneforvariousmagnitudesoftipmassandvariouslevelsofsubmergence.ThecomputationalefficiencyandaccuracyoftheRayleigh-Ritzmethod,ascomparedtotheFEA,hasbeendemonstrated.Theadvantageofusingclosed-formtrialfunctionsisclearlyseenintheefficacyofcalculatingthevariousenergycomponentsintheRRmethod.