简介:Strongrestrictionsonemissionsfrommarinepowerplants(particularlySOx,NOx)willprobablybeadoptedinthenearfuture.Inthispaper,acombinedsolidoxidefuelcell(SOFC)andsteamturbinefuelledbynaturalgasisproposedasanattractiveoptiontolimittheenvironmentalimpactofthemarinesector.TheanalyzedvariantofthecombinedcycleincludesaSOFCoperatedwithnaturalgasfuelandasteamturbinewithasingle-pressurewasteheatboiler.ThecalculationswereperformedfortwotypesoftubularandplanarSOFCs,eachwithanoutputpowerof18MW.Thispaperincludesadetailedenergyanalysisofthecombinedsystem.Massandenergybalancesareperformednotonlyforthewholeplantbutalsoforeachcomponentinordertoevaluatethethermalefficiencyofthecombinedcycle.Inaddition,theeffectsofusingnaturalgasasafuelonthefuelcellvoltageandperformanceareinvestigated.Ithasbeenfoundthatahighoverallefficiencyapproaching60%maybeachievedwithanoptimumconfigurationusingtheSOFCsystem.Thehybridsystemwouldalsoreduceemissions,fuelconsumption,andimprovethetotalsystemefficiency.
简介:《73/78防污公约》2004年修正案在“船上油污应急计划”中增加条款规定“所有载重量为5000吨或以上的油船均应可以立即使用岸基破损稳性和剩余结构强度电脑计算程序”,修正案生效后,我国政府立即响应,发出了执行新的修正案的通知(海船舶[2006]629号)。为了能够切实履行公约修正案,本文在研究了公约的背景、国外履约的情况及我国现状的基础上,提出了相应对策及海事管理建议。
简介:对大连海事大学图书馆航海、轮机技术学科类中文图书2001~2004年的流通和利用情况作了统计,应用文献流通率和文献利用率进行分析,并提出整改建议.
简介:首先对2015海员人力资源报告(2015BIMCO/ICS)中的有国际航运业可提供的有资质的海员数量和行业对海员的需求数量、未来十年国际商船队规模的增长情况以及其对未来国际海员供求情况的影响等一些重要问题做出总结,之后分析中国海员劳动力市场现状和存在的问题。最后,结合两者,对未来中国航海教育和培训的发展以及如何把握机遇发展中国海员队伍的相关问题做出讨论。
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.