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:Applicationsofcomputationalfluiddynamic(CFD)tothemaritimeindustrycontinuetogrowwiththeincreasingdevelopmentofcomputers.Numericalapproacheshaveevolvedtoalevelofaccuracywhichallowsthemtobeappliedforhydrodynamiccomputationsinindustryareas.Hydrodynamictests,especiallyplanar-motion-mechanism(PMM)testsaresimulatedbyCFDsoftware-FLUENT,andallofthecorrespondinghydrodynamiccoefficientsareobtained,whichsatisfytheneedofestablishingthesimulationsystemtoevaluatemaneuverabilityofvehiclesduringtheautonomousunderwatervehicleschemedesignstage.Theestablishedsimulationsystemperformedwellintests.
简介:城市轨道交通车辆以电能为动力电源,城轨在建设和运营阶段,虽然牵引供电的安全性和可靠性得到了足够重视,但仍不可避免地因供电系统故障、人为破坏、偶发因素自然灾害等引起城轨车辆供电短时中断或长时间瘫痪,造成列车无法正常运行。所以增加备用电源装置,当城轨供电系统突然发生供电故障时,列车可以通过备用电源装置设备进行供电,实施紧急自牵引,根据实际线路要求牵引至邻近站台,实现清客、回库的目的,并且在此过程中备用电源提供电能保障必要的基础设施运行。目前备用电源设备多采用车载电池方式来实现。虽然此方式在一定程度上解决了列车供电故障带来的影响,但是由于列车牵引功率和能量较大,所以需要的电池体积和重量也就比较大,增加了列车运行负载;同时电池价格昂贵,只作为备用电源装备在列车上,从经济性方面考虑成本较高,效益较低。
简介:Inordertostudytheeffectsofgeometricparametersoftherudderonthehydrodynamicperformanceofthepropeller-ruddersystem,thesurfacepanelmethodisusedtobuildthenumericalmodelofthesteadyinteractionbetweenthepropellerandruddertoanalyzetherelevantfactors.Theinteractionbetweenthepropellerandrudderisconsideredthroughtheinducedvelocities,whicharecircumferentiallyaveraged,sotheunsteadyproblemistranslatedtosteadystate.Aniterativecalculationmethodisuseduntilthehydrodynamicperformanceconverges.Firstly,thehydrodynamicperformanceofthechosenpropeller-ruddersystemiscalculated,andthecomparisonbetweenthecalculatedresultsandtheexperimentaldataindicatesthatthecalculationprogramisreliable.Then,thevariableparametersofrudderareinvestigated,andthecalculationresultsshowthatthepropeller-rudderspacinghasanegativerelationshipwiththeefficiencyofthepropeller-ruddersystem,andtherudderspanhasanoptimalmatchrangewiththepropellerdiameter.Futhermore,therudderchordandthicknessbothhaveapositivecorrelationwiththehydrodynamicperformanceofthepropeller-ruddersystem.
简介:综合电力系统概念正处于全尺寸预研试验之中,到目前为主要工作集中于各种IPS模块和系统运行的相互关系上。随着各种功能,接口和打互可操作性问题的解决,重点工作正在转向整个系统的控制逻辑优化,与各种支撑系统的接口和与舰船各任务的控制器的接口方面。本文描述当前IPS和控制概念的结构,象电力管理,较低级别控制器的自主最大化和网络的物理及逻辑接口等令人关注的设计工作正在进行,此外,分析了IPS与辅助支撑系统的相互关系所代表的控制要求和人员减少的要求,这些问题的解决办法必须与能负担得起的人员最少化系统相一致。对独立性和生命力问题也有所讨论,本文还基于技术发展趋势和前期研究成果介绍了未来IPS战舰用的富有生命力的结构和功能,建议了进一步研究领域。
简介:Forstudyingthedynamicperformanceofsubseaumbilicalcablelayingsystemandachievingthegoalofcabletensionandlayingspeedcontrol,therigidfiniteelementmethodisusedtodiscreteandtransformthesystemintoarigid-flexiblecouplingmulti-bodysystemwhichconsistsofrigidelementsandspring-dampingelements.ThemathematicalmodelofsubseaumbilicalcablelayingsystemkinematicchainispresentedwiththesecondorderLagrangeequationinthejointcoordinatesystem,anddynamicmodelingandsimulationisperformedwithADAMS.Thedynamicanalysisisconductedassumingthefollowingthreestatuses:ideallaying,practicallayingunderwavedisturbance,andpracticallayingwithtensioncompensation.Resultsshowthatmotiondisturbancesofthelayingbudgeunderseawaves,especiallywithheavingandpitching,willcauserelativelyseriousfluctuationsincabletensionandlayingspeed.Tensioncompensation,i.e.,activebacktensiontorquecontrolcanrestrictcontinuoustensionincreasingordecreasingeffectivelyandrapidly,thusavoidingcablebreachorbuckling.
简介:简要概述了可变转向助力系统的发展应用情况。介绍了法国标致汽车公司605型高级轿车所采用的电子控制可变转向助力系统的结构与工作原理,详细分析了双腔分配控制阀、电子伺服调节阀的结构与作用过程,对电控系统与油压系统的检修作了简要介绍。
简介:Reconfigurabilityoftheelectricalnetworkinashipboardpowersystem(SPS)afteritsfailureiscentraltotherestorationofpowersupplyandimprovessurvivabilityofanSPS.Thenavigationalprocesscreatesasequenceofdifferentoperatingconditions.Thepriorityofsomeloadsdiffersinchangingoperatingconditions.AfteranalyzingcharacteristicsoftypicalSPS,amodelwasdevelopedusedagradeⅢswitchboardandanenvironmentalprioritizingagent(EPA)algorithm.Thisalgorithmwaschosenasitislogicallyandphysicallydecentralizedaswellasmulti-agentoriented.TheEPAalgorithmwasusedtodecideonthedynamicloadpriority,thenitselectedthemeanstobestmeetthemaximumpowersupplyload.Thesimulationresultsshowedthathigherpriorityloadswerethefirsttoberestored.Thesystemsatisfiedallnecessaryconstraints,demonstratingtheeffectivenessandvalidityoftheproposedmethod.