简介:回顾STCW公约马尼拉修正案关于船员培训与发证的新要求,总结近几次国际海事组织船员培训与值班分委会有关船员培训与发证议题的审议情况,分析后马尼拉修正案时期船员培训与发证国际标准的新变化,提出对我国应采取的应对措施。
简介:Smoothedparticlehydrodynamics(SPH)isaLagrangianmeshlessparticlemethod.Itisoneofthebestmethodforsimulatingviolentfreesurfaceflowsinfluidsandsolvinglargefluiddeformations.Dambreakingisatypicalexampleoftheseproblems.ThebasisofSPHwasreviewed,includingsometechniquesforgoverningequationresolution,suchasthesteppingmethodandtheboundaryhandlingmethod.Thennumericalresultsofadambreakingsimulationwerediscussed,andthebenefitsofconceptslikeartificialviscosityandpositioncorrectionwereanalyzedindetail.Whencomparedwithdambreakingsimulatedbythevolumeoffluid(VOF)method,thewaveprofilegeneratedbySPHhadgoodagreement,butthepressurehadonlyreasonableagreement.Improvingpressureresultsisclearlyanimportantnextstepforresearch.
简介:<正>19–24October2014SingaporeCONFERENCETHEMESTheoverallaimoftheICHDConferenceistoprovideaforumforparticipantsfromaroundtheworldtoreview,discussandpresentthelatestdevelopmentsinthebroaddisciplineofhydrodynamicsandfluidmechanics.ThefirstInternationalConferenceonHydrodynamics(ICHD)wasinitiatedin1994inWuxi,China.Sincethen,9moreICHDconferenceswereheldsubsequentlyinHongKong,Seoul,Yokohama,Tainan,Perth,Ischia,Nantes,ShanghaiandStPetersburg.EvidentlytheICHDconferencehasbecomeanimportanteventamongacademics,
简介:TheReynolds-averagedNavier-Stokes(RANS)method,alongwiththeFluentsoftwarepackage,wasusedtostudythesteadyandunsteadyinteractionofpropellersandrudderswithadditionalthrustfins.Theslidingmeshmodelwasemployedtosimulateunsteadyinteractionsbetweentheblades,therudderandthethrustfins.Basedonthenumericalresults,thepressuredistributiononthepropellerandtheefficiencyofthefinswerecalculatedasafunctionoftheattackangle.TheRANSresultswerecomparedwithresultscalculatedbythepotentialmethod.ItwasfoundthattheresultsforthepotentialmethodandtheRANSmethodhavegoodconsistency,buttheyyieldmaximumefficienciesforthefins,andthuscorrespondingattackangles,thatarenotidentical.
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:Theprogressofeconomicglobalization,therapidgrowthofinternationaltrade,andthemaritimetransportationhasplayedanincreasinglysignificantroleintheinternationalsupplychain.Asaresult,worldwideseaportshavesufferedfromacentralproblem,whichappearsintheformofmassiveamountsoffuelconsumedandexhaustgasfumesemittedfromtheshipswhileberthed.Manyportshavetakenthenecessaryprecautionstoovercomethisproblem,whileothersstillsufferduetothepresenceoftechnicalandfinancialconstraints.Inthispaper,thebarriers,interconnectionstandards,rules,regulations,powersources,andeconomicandenvironmentalanalysisrelatedtoships,shore-sidepowerwerestudiedineffortstofindasolutiontoovercomehisproblem.Asacasestudy,thispaperinvestigatesthepracticability,costsandbenefitsofswitchingfromonboardshipauxiliaryenginestoshore-sidepowerconnectionforhigh-speedcraftscalledAlkaherawhileberthedattheportofSafaga,Egypt.Theresultsprovidethenationalelectricitygridconceptasthebesteconomicalselectionwith49.03percentofannualcostsaving.Moreover,environmentally,itcouldachieveanannualreductioninexhaustgasemissionsofCO2,CO,NOx,P.M,andSO2by276,2.32,18.87,0.825and3.84tons,respectively.
简介:本文探讨了运用“双向选择:的分配方式解决航海类专业非船员标准毕业生的分配问题的实施原则、优越性及存在的问题,对航海类专业毕业生分配工作有一定的借鉴作用。
简介:针对船舶动力系统润滑油水分检测耗时长的问题,根据润滑油导电性随含水率变化的特点,设计出基于电导传感器的润滑油水分在线、实时检测系统,系统通过获得电导传感器测量油水混合液的输出电压计算润滑油的含水率。该仪器主要包括电导传感器与激励源模块、单片机STM32F103C8模块、信号采集模块和液晶显示模块等构成。实验结果表明电导传感器润滑油水分检测系统能够准确、方便、快速地实现检测功能。
简介:该报告描述一条预设海底管道的基于定量风险分析(QRA)的泄漏检测标准(LDC)设计问题.定量风险分析的结果会反映出统计泄漏检测方法是否必要.如果必要,恰当的泄漏检测标准必须建立.在分析中,著名的英国PARLOC2001数据库将会用来估算管道实效概率。而来自MMS的POSVCM模型则用来做泄漏模拟计算.定量风险分析的结果说明,统计方法的泄露检测系统能打幅度地减少泄漏检测所需时间,从而减轻泄露的事故后果.根据QRA的分析结果,以及许多泄漏检测系统买主的建议,合理的西漏检测标准被设计出来.一旦泄漏事故产生,它可以帮助紧急事故相应组(ERT)快速检测,定位以及采取方法减轻泄漏.