简介:包含磷氮(MSMM-Al-P)的新奇包含的火焰retardant被与聚酰胺66包含准备(PA66-MSMM-Al-P)为聚酰胺6的火焰延迟(PA6)。结构和PA66-MSMM-Al-P的热性质被Fourier变换红外线的光谱学,X光检查光电子光谱学和thermogravimetric分析描绘。包含火焰retardants(MSMMAl-P和PA66-MSMM-Al-P)的PA6易燃被限制的氧索引测试,垂直燃烧测试和锥热量计调查。火焰retardancy和锥calorimetric分析在flame-retardantPA6建议了在PA66和MSMM-Al-P之间的synergistic效果。flame-retardantPA6的热稳定性也被调查。
简介:Flamestructuresofasyngasswirl-stabilizeddiffusionflameinamodelcombustorweremeasuredusingtheOH-PLIFmethodunderdifferentfuelandairswirlintensity.Theflameoperatedunderatmosphericpressurewithairandatypicallowheating-valuesyngaswithacompositionof28.5%CO,22.5%H2and49%N2atathermalpowerof34kW.Resultsindicatethatincreasingtheairswirlintensitywiththesamefuel,swirlintensityflamestructuresshowedlittledifferenceexceptasmallreductionofflamelength;butalso,withthesameairswirlintensity,fuelswirlintensityshowedgreatinfluenceonflameshape,lengthandreactionzonedistribution.Therefore,comparedwithairswirlintensity,fuelswirlintensityappearedakeyeffectontheflamestructureforthemodelcombustor.InstantaneousOH-PLIFimagesshowedthatthreedistincttypicalstructureswithanobviousdifferenceofreactionzonedistributionwerefoundatlowswirlintensity,whileamuchcompacterflamestructurewithasingle,stableanduniformreactionzonedistributionwasfoundatlargefuel-airswirlintensity.Itmeansthatlargerswirlintensityleadstoefficient,stablecombustionofthesyngasdiffusionflame.
简介:Thepresentpaperdealswiththeuseofanewpolymericflameretardantmaterial,polyphenylenesulphide(PPS)forplastics.Incorporationof15—20%PPSintonylon-6hasprovidedULV-0ratingforthesystemandthereisenhancementintensileandflexuralproperties.Theresultsobtainedonthethermal,crystallizationandflowcharacteristicsofthenylon-PPSsystemuptoaloadingof40%PPSarealsodiscussed.
简介:Theinfluencelawofammoniumpolyphosphate(APP)andcouplingagentsonthemechanicalpropertiesandflameretardantpropertiesofwoodpowder/PEcompositeswerestudiedbymechanicaltestandlimitedoxygenindex(LOI)test.TheexperimentalresultsshowthattheLOIofcompositesincreasedfrom18.7%to26.5%whenthecontentofAPPflameretardantwas30%,howeverthemechanicalpropertiesdecreased.ThemaleicanhydridegraftPP,titanateandsilanecouplingagentwereusedtoimprovemechanicalpropertiesofcompositesanditwasimpliedthattitanateandsilanecouplingagentcanimprovethemechanicalpropertiesofcompositesobviously.Thelimitedoxygenindexofwoodpowder/PEcompositesreached27.5%whenthecontentoftitanatewas2%.Thermogravimetricanalysis(TGA)showsthatAPPpromotedcharringandincreasedtheamountsofchar,thusprotectingtheinnermatrixandincreasedtheamountofresidualcharathighertemperature.Thetitanatecouplingagentfurtherincreasedthecharringformedandstrengthenedthethermalstability,soobviouslyincreasedtheflameretardantofcomposites.
简介:铝次磷酸盐(AHP)的效果作为火焰retardancy和包含铵polyphosphate(应用软件)和triazine的膨胀火焰retardant聚丙烯composites(PP/IFR)的热降级行为上的一个synergistic代理人,起泡沫嘉鱼之类的代理人(CFA)被限制氧索引(LOI)调查,UL-94测量,thermogravimetric分析(TGA),锥热量计测试(锥),扫描电子显微镜学(SEM)和X光检查光电子光谱学(XPS)。有AHP的IFR的联合展出了明显的synergistic效果并且为PP矩阵提高了火焰retardant效率,这被发现。有0.8公里的厚度的标本能递给UL-94评价的V-0,LOI价值基于24wt%,和AHP/IFR的最佳团部分的火焰retardant装载的总数到达33.5%是1:6。TGA数据表明AHP能改变IFR和PP/IFR系统的降级行为,在高温度提高IFR和PP/IFR系统的热稳定性并且支持字符残余形成。锥结果表明IFR/AHP混合能高效地减少PP的燃烧参数,例如热版本率(HRR),全部的热版本(THR),烟生产率(SPR)等等。字符残余的词法结构证明AHP在烧期间具有材料表面上的更紧缩、同类的字符层的形成的利益。XPS的分析显示AHP可以在材料表面上支持足够的字符的形成并且改进火焰retardant性质。
简介:这份报纸集中于调查相互作用效果为打漩并且在稳定的火焰过程直率身体。粒子图象velocimetry被用来在三个炉子测量速度领域。首先,在直率身体的稳定的炉子有或没有的火焰的比较打漩被介绍。实验的结果介绍直率身体的稳定的火焰的变化什么时候打漩,被增加进炉子:最大的反向的流动速度和最大的平均数平均光线的速度减少;最大的光线的根平均数摆平波动(rms)速度增加;嘴轴的方面上的轴的速度山峰的价值更低,并且在山峰和中心线之间的距离更大;最大的光线的rms速度的地点从中央再通行地区(CRZ)搬到环形的气流的插头。然后,火焰在的比较打漩炉子有或没有直率身体被提供。实验的结果显示出打漩的变化火焰什么时候直率身体被增加进打漩炉子:在CRZ的空气旋涡搬到炉子;轴的平均数和rms速度减少的山峰价值;在中心线和轴的平均数和rms速度山峰增加之间的距离;吝啬的光线的速度减少的山峰,和rmsraidial速度增加的山峰。从这个实验的数据能也为燃烧的发展和确认作为基准被建立数字模拟。
简介:Inthispaper,variousstrategiesofspiralirradiatingschemefortheflameformingofabowlshapedsurfaceareinvestigatedexperimentallyandnumerically.Experimentalworkisperformedusingaflametorchintegratedwitha2-axisCNCworkstation.TheABAQUSimplicitsolverisusedinthenumericalsimulation.Threedifferentstrategiesofthespiralirradiatingschemeareinvestigatedfortheflameformingofabowlshapedsurface.ThefirststrategyistheSimplespiralirradiatingscheme,thesecondistheRotationalspiralirradiatingscheme,andthethirdistheSymmetrical-Rotationalspiralirradiatingscheme.TheresultsshowthatusingtheSymmetricalRotationalspiralirradiatingscheme,abowlshapedsurfacewiththemaximumdeformationcanbeproduced,followedbyusingtheRotationalscheme,andtheSimplespiralscheme.ItisalsoconcludedfromtheresultsthatthespiralirradiatingschemewithSymmetrical-Rotational,RotationalandSimplespiralschemesleadtothemaximumsymmetriesintheproducedbowlshapedsurface,respectively.Allthenumericalresultsareingoodagreementwiththeexperimentalobservations.
简介:Anewlydesignedstrutisproposedinthispaperforfuelinjectionandflameholdinginaliquid-kerosene-fueledsupersoniccombustor.Thethicknessofthestrutis8mmandthefrontblockageisabout8%.Thecharacteristicofthisstrutisthatextraoxygencanbeinjectedthroughasetoforificesatthebackofthestrut,whichcanchangethelocalflowfieldstructureandER(EquivalenceRatio).Basedontheabovementionedstrut,astablelocalflameisgeneratedatthebackofthestrutandthemaincombustioncanbeorganizedaroundthislocalfire.Numericalsimulationisconductedtocomparethelocalflowfielddistributionatthebackofthestrutwith/withoutextraoxygeninjection.Experimentsareconductedtotestthecombustioncharacteristicsbasedonthisfuelinjectionandflameholdingstrategy.Thetemperaturedistributionwhichcanreflectthelocalflamecharacteristichasbeenmeasuredintheexperimentsconductedundercoldincomingsupersonicairflowcondition.Inaddition,theoverallcombustionperformanceinafull-scalesupersoniccombustorhasbeenevaluatedintheexperimentsconductedunderhotincomingsupersonicairflowcondition.Resultsshowthatthisstrutstrategyisverypromisingsinceitcanorganizestablesupersoniccombustionatthecenterofthecombustorwithoutanycavityorrearwardfacingstep.Besidesthat,evenwiththe8mmthickstrut,thecombustioncanbestableinawiderangeofERfrom0.25-1byusingliquidroom-temperaturekerosene.
简介:Thecontrollableactivethermo-atmospherecombustor(CATAC)hasbecomeautilizableandeffectivefacilitybecauseitbenefitstheopticaldiagnosticsandmodeling.Thispaperpresentsthemodelingresearchoftheauto-ignitionandflamesoftheH2/N2(H2/CH4/N2,orH2/H2O2/N2)mixtureonaCATAC,andshowscurvesvaryingwithtemperaturesofauto-ignitiondelay,theheightofthesiteofauto-ignitionofliftedflames,andflamelift-offheight.Theresultsofauto-ignitiondelayandthelift-offheightarecomparedtheexperimentalresultstovalidatethemodel.Aturningpointcanbeseenoneachcurve,identifiedwithcriteriontemperature.Itcanbeconcludedthatwhentheco-flowtemperatureishigherthanthecriteriontemperature,theauto-ignitionandliftedflameofthemixturearenotstable.Conversely,belowthecriteriontemperature,themixturewillauto-igniteinastablefashion.Stabilizationmechanismsofauto-ignitionandliftedflamesareanalyzedintermsofthecriteriontemperature.
简介:Anovelopticalinstrumentationsystemforflamecharacterizationwasdevelopedandtested.Thetwo-colorsystemiscapableofperformingon-linemeasurementofflameandtemperaturedistribution,providingtemporalandspatialcharacterizationofthecombustionprocess.Inaddition,thesystemhastheadvantageofbeingnon-intrusive.Theon-linemeasurementoftemperaturedistributiononamethane-aircombustorrevealedsomeinterestingcharacteristics.Whenairflowratewaskeptconstant,anincreaseinCH4flowratewouldenhancethecombustionintensityandelevatetheflametemperature.WhileunderconstantCH4flowrate,theincreaseofairflowratewouldleadthemeasuredflametemperaturefirsttoincreaseandthendecrease.Thedropoftemperaturemightpartiallybecausedbytheheatlossesduetoexcessiveair.However,withinsufficientsootparticlesintheflame,thetemperaturecouldbeunder-evaluated.
简介:为本地人的明确的表情,即时没有生产率模型被建议不在狂暴的甲烷空气模仿形成燃烧。混合部分和分级的驱散的平均生产率通过二单个变量的概率密度功能的近似从渐近线被获得。理论在theoxygen消费地区从氧化氩氮的机制从Zel-dovich机制,而是可以忽略的贡献预言了重要贡献。建议模型被用来不在pilotmethane空气喷气散开燃烧模仿形成。模拟结果与CFD软件获得的那些相比是流畅的模块。有USA的SandiaNational实验室给的试验性的数据的预言的确认显示建议模型比另外的模型产出更好的结果,并且偏差不到5%。并且在一些完全反应地区,模拟结果与试验性的数据一样是平的。压力模型和standardk-ω建模的雷纳德可实现的k-ε模型也被调查预言狂暴的燃烧反应,它证明模拟由ω模型根据试验性的数据的标准k-燃烧生产的速度,温度,和集中结果。