简介:我们集中于与Ni-Al金属间化合的混合物扔合金由的ligth重量的表面加强在原处改进非铁的扔的表面性质的燃烧反应部件。在我们的以前的工作,元素的Ni和艾尔粉末紧缩的绿色被SHS(自我繁殖的高温度合成)反应到形式Ni3Al金属间化合的化合物有熔融的艾尔合金并且同时的热的反应与艾尔扔结合了合金。但是象微小的裂缝和孔那样的一些缺点在反应协议被仍然是。我们因此使用了压力阻止热裂缝并且与液体艾尔合金充满毛孔由压榨扔过程。压缩艾尔合金与Ni3Al金属间化合的混合物结合了是sectioned并且由光显微镜学和扫描电子显微镜学(SEM)观察了。在结合的接口附近并且在反应协议形成的intermetallics的stoichiometric作文被散光谱学(版本)和电子探查的精力识别微分析(EPMA).Si富人层被艾尔的顺序的团结在结合的接口附近在艾尔合金方面上形成合金。在反应Ni3Al协议观察的孔与液体艾尔合金被充满。从熔融的艾尔合金的Si粒子在反应Ni3Al金属间化合的协议的毛孔被检测。扔合金和Ni3Al金属间化合的化合物的艾尔被把压力用于液体艾尔合金很很熟加入。
简介:Thispaperprovidesanumericalanalysismodelofunsteadyheattrans-ferinpiston-linersetofaninternalcombustionengine.Themodelsimulatestheun-steadyheattransferprocessamongthecombustionmixture,pistonset,lubricantfilm,linerandcoolantinawholeenginecycle,andcanpredictthetemperaturefluc-tuationanddistributiononpistoncrown,innersurfaceofliner,pistonringandthelubricantfilm.Acomputerprogramisdevelopedtocalculatetheunsteadyheattrans-ferprocessofpiston-linersysteminawater-cooleddieselengine.
简介:CuO/γ-Al2O3catalystswerepreparedbyplasmatreatmentandconventionalimpregnationmethods.Thecatalyticcombustionoftwokindsofvolatileorganiccompounds(VOCs),tolueneandbenzene,werecarriedoutovertheseCuO/γ-Al2O3catalysts.ThesurfacepropertiesofthesecatalystswerecharacterizedbyX-rayDiffraction(XRD)andScanningElectronMicroscopy(SEM).TheexperimentalresultsshowedthatincatalyticcombustiontheactivityoftheCuO/γ-Al2O3catalystpreparedviaplasmawasmuchhigherthanthatoftheCuO/γ-Al2O3catalystpreparedbyconventionalimpregnationmethod.XRDresultsshowedthatanenhanceddispersionhadbeenachievedwiththeplasmatreatment.SEMresultsindicatedthatthesizebecamemuchsmallerandthesurfacebecamemoreuniformwiththeplasmatreatment.
简介:NanosizedBaCeo.95Yo.o5O3-δpowderswiththehomogeneouscompositionweresynthesizedbyanewcombustionprocessbasedonthePechinimethod.Apolymericprecursorsolwasformedbyuseofcitricacidandethyleneglycolasthechelatingagentsofmetalions.Theperovskite-typeBaCeo.95Yo.o5O3-δpowderswithuniformshapeandsmallerthan40nminsizedwereobtainedthroughthecombustionofthepolymericprecursorsolattheexistenceofnitricacidandammoniumhydroxide.Itwasfoundtheparticlesizecouldbecontrolledbymodulatingthequantitiesofnitricacidandammoniumhydroxide,thequantitiesoftheresidue,carbonateionswerealsoaffectedbythequantitiesofthecitricacidandethyleneglycol.
简介:Theresincompositematerials(RCM)werepreparedbythemethodofdopingresinwithtourmalinepowdersmodifiedwithlanthanumelement.Itwascharacterizedbyscanningelectronmicroscope(SEM),IRradiationdetermination,X-raydiffraction(XRD),andfouriertransforminfraredspectroscope(FTIR).TheresultsshowedthattheRCMcouldradiatehigherintensityoffarinfrared.Themolecularmovementwasstrengthenedandtheinter-molecularcontactswereeasilyreducedwhenthedieseloilwasdealtwiththeRCM.TheeffectsoftheRCMontheoilconsumptionandairpollutantemissionsofoil-burningboilerwereinvestigated.Theoil-savingrateoftheRBS·VH-1.5boilerdealtwiththeRCMwas2.76%,andthereducingratesofCOandNOintheexhaustgaswere32.9%and15.8%,respectively.
简介:Athree-dimensionalmathematicalmodelofthecombustionofpulverizedcoalandcokehasbeendeveloped.Themodelisappliedtotheblowpipe-tuyere-raceway-cokebedregioninanironmakingblastfurnaceinonecomputationaldomain,whichincludestwoparts:pulverizedcoalcombustionmodelintheblowpipe-tuyere-racewaycavityandthecoal/cokecombustionmodelinthesurroundingcokebed.Theeffectsofcoalpropertiesareexaminedcomprehensively,intermsofcoalburnoutandgasspeciesdistributions.TheresultsindicatethatusingacoaloffineparticlesizeorhighVMcontentcouldimproveburnoutandwouldaffectthegascompositionconsiderably.Theburnoutisexaminedintwoways:comparedwithburnoutalongtuyereaxis,burnoutovertheracewaysurfaceisamoresensitiveandsensibleparametertodescribetheamountofunburntcharenteringthecokebed.Themodelisusefulforexaminingtheflow-thermo-chemicalcharacteristicsofthepulverizedcoalinjection(PCI)processundervariousconditionsinablastfurnace.
简介:Besedonpreviousstudies,animprovednon-slaggingspouting-cyclonecombustorwithtwo-stagecombustion,organizedinperpendicularlyvortexingflows,isdevelopedforcleancoalcombustionappliedissmall-sizeindustrialfurnacesanddomesticfurnaces.Theisothermalmodeltestandthecombustiontestgivesomeencouragingresults.Inthisstudy,furtherimprovementofthegemoetricalconfigurationwasmade,avisualizationmethodandaLDAsystemwereusedtostudythegas-particleflowbehaviorandthetemperatureandgascompositionincombustionexperimentsweremeasuredbyusingthermocouplesandaCOSA-6000-CDPortableStackAnalyzer.Strongerrecirculationinthesopoutingzoneandthestronglyswirlingefectinthecyclonezonewereobtainedintheimprovedcombustor.Thecombustiontemperaturedistributionisuniform.Theseresultsindicatethattheimprovedgeometricalconfigurationofthecombustorisfavorabletothestabilizationofcoalflameandtheintensificationofcoalcombustion.andisprovidesabasisforthepracticalapplicationofthistechnique.
简介:Effectsofexhaustgasrecirculation(EGR)onhomogeneouschargecombustionofn-heptanewasstudiedthroughsimulationandexperiment.Experimentswerecarriedoutinasinglecylinder,four-stroke,aircooledengineandasinglecylinder,two-stroke,watercooledengine.Inthefour-strokeengine,experimentsoftheeffectsofEGRwereexaminedusingheatedN2additionasasurrogateforexternalEGRandmodifyingenginetoincreaseinternalEGR.TheignitiontimingwassensitivetoEGRduetothermalandchemicaleffects.EGRorextraairisakeyfactorineliminatingknockduringmid-loadconditions.Forhigherloadoperationtheonlywaytoavoidknockistocontrolreactiontimingthroughtheuseofsparkignition.Experimentalandmodelingresultsfromthetwo-strokeengineshowthatauto-ignitioncanbeavoidedbyincreasingtheenginespeed.Thetwo-strokeengineexperimentsindicatethathighlevelsofinternalEGRcanenablesparkignitionatleanconditions.Athigherloadconditions,increasingtheenginespeedisaneffectivemethodtocontroltransitionfromhomogeneouschargecompressionignition(HCCI)operationtonon-HCCIoperationandsuccessfulsparkignitionofahighlydilutemixturecanavoidseriousknock.
简介:Theblended-fuelbasededdy-dissipation-conceptcombustionmodelwasnewlydevelopedintheFireFOAMframework,andappliedtosimulate30cm×30cmheptane-ethanolpoolfire.Comparisonwasmadeoffireheight,centerlinetemperatureagainstexperimentalmeasurements,whichshowsthattheymatchverywellwitheachother.However,furtherstudiesareneededtoexaminethevalidationofthismodelinfiresimulationswithvariousscales.
简介:当引擎使用与纳米大小的添加剂Ce0.9Cu0.1O2和Ce0.9Zr0.1O2混合的重油时,这篇论文主要在高速度的柴油机引擎和排放减小的表演上学习。在测试期间,Indiset620燃烧分析器由AVL做了,被用来在柱体压力上做即时调查,燃料点火时刻,并且在柱体和曲柄角度建立在温度的变化趋势之间的一种关系。为烧与添加剂混合的重油和重油的引擎,燃烧分析软件Indicom和协奏曲被用来分析它的燃烧进程和排放条件。试验性的调查证明缩放nano的复杂氧化物能改进与重油,和还原剂造成的柴油机引擎的表演象NOx和公司一样的污染物质的排放,把它与纯重油作比较。根据这个实验的后果,添加剂在重油的使用改进全面表演。
简介:Chemical-loopingcombustion(CLC)isanovelcombustiontechniquewithinherentCO2separation.Magnetite(Fe3O4)wasselectedastheoxygencarrier.Shenhuacoal(InnerMongolia,China),strawcokeandnaturalcokewereusedasfuelsforthisstudy.Influencesofoperationtemperatures,coaltoFe3O4massratios,anddifferentkindsoffuelsonthereductioncharacteristicsoftheoxygencarrierwereinvestigatedusinganatmospherethermogravimetricanalyzer(TGA).Scanningelectronmicroscopy(SEM)wasusedtoanalysethecharacteristicofthesolidresidues.Experimentalresultsshownthatthereactionbetweenthecoalandtheoxygencarrierbecomestrongatatemperatureofhigherthan800℃.Astheoperationtemperaturerises,thereductionconversionrateincreases.Atthetemperaturesof850oС,900℃,and950℃,thereductionconversionrateswere37.1%,46.5%,and54.1%respectively.However,SEMimagesshowthatatthetemperatureofhigherthan950℃,theironoxidesbecomemeltedandsintered.Thepossibleoperationtemperatureshouldbekeptaround900℃.WhenthemassratiosofcoaltoFe3O4were5/95,10/90,15/85,and20/80,thereductionconversionrateswere29.5%,40.8%,46.5%,and46.6%respectively.Withtheincreaseofcoal,theconversionrategoesup.Butthereexistanoptimalratioaround15/85.Comparisonsbasedondifferentkindsoffuelsshowthatthesolidfuelwithahighervolatileandamoredevelopedporestructureisconducivetothereductionreactivityoftheoxygencarrier.
简介:Inthepresentpaper,amultifluidmodeloftwo-phaseflowswithpulverized-coalcombustion,basedonacontinuum-trajectorymodelwithreactingparticlephase,isdevelopedandemployedtosimulatethe3-Dturbulenttwo-phaseflowsandcombustioninanewtypeofpulverized-coalcombustorwithoneprimary-airjetplacedalongthewallofthecombustor.Theresultsshowthat:(1)thiscontinuum-trajectorymodelwithreactingparticlephasecanbeusedinpracticalengineeringtoqualitativelypredicttheflamestability,concentrationsofgasspecies,possibilitiesofslagformationandsootdeposition,etc.;(2)largerecirculationzonescanbecreatedinthecombustor,whichisfavorabletotheignitionandflamestabilization.