简介:〔摘要〕燃料电池是原电池的一个重要考点,燃料电池正极反应式本质都是氧气被还原为O2-,一定环境中O2-借助于载体存在;而负极的书写要注意电荷守恒配平,书写电极方程式的关键是要注意注意电解质环境。
简介:将质量比90%的柴油分别掺混10%菜籽油,10%DMC以及5%菜籽油和5%DMC的混合物,连同纯柴油组成10%RO,10%DMC,5%R0+5%DMC和柴油共4种燃料,在一台单缸柴油机上进行燃烧、性能及排放试验研究.结果表明:含氧燃料的特性不同对比燃油消耗率和热效率影响较小,但对燃烧和排放影响较大.3种含氧燃料对柴油机缸内最大爆发压力影响不大.与柴油相比,柴油机燃用5%RO+5%DMC和10%R0时,放热率峰值降低,滞燃期缩短,燃烧始点提前.燃用10%DMC时放热率峰值上升,滞燃期延长,着火延迟.与燃用柴油相比,柴油机燃用5%RO+5%DMC和10%DMC时,除烟度有所下降以外,CO,HC和NOx排放均高于柴油.柴油机燃用10%RO时的烟度和Hc排放均低于柴油,而CO和NOx排放高于柴油.
简介:配气机构、曲柄连杆机构和燃料供给系统、冷却系统、润滑系统是发动机的重要构造部件,是维持柴油机长期工作不可缺少的部分,其工作好坏对发动机的动力性和经济性以及零件磨损影响很大,本文介绍了发动机的两大机构和三大系统中的燃料供给系统的具体工作模式作了详细的论述和分析,对发动机的使用保养有较大的指导意义。
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:微型燃料电池热电联产系统主要由燃料处理单元、产电单元和其他一些辅助单元构成。燃料处理单元主要由自热重整反应器、高温水气变换反应器、低温水气变换反应器和CO优先氧化反应器组成。利用AspenPlus软件模拟了干瓦级的微型燃料电池热电联产系统的工艺流程,借助能量和[火用]分析方法对该系统的整体性能和系统各组成部分的性能进行了详细的分析。对典型案例下的各组成单元的能量损耗和[火用]损耗进行了详细分析。结果显示系统的能量和[火用]损失主要是由于驰放气和烟气等排放造成。系统的所有单元中质子交换膜燃料电池的能量效率和[火用]效率最小。对水碳比、氧碳比、氢气利用率、发电效率和甲烷进料量对整个系绕性能影响也进行了能量与[火用]分析。
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.