学科分类
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6 个结果
  • 简介:Thediaphragmofsteamturbineisoneofthemainpartsofthepassageunitforairflowingandthediaphragmofsteamturbineisgenerallymadebywelding,butduringthecourseofwelding,somecracksoftenhavehappened,thesecracksthreatensafetyproductiononthespot,soitisnecessarytoanalyzethestrengthofsteamturbinediaphragmwithacrack.Forstudyingitsworkingconditionandperformancewithacrack,thethree-dimensionalfiniteelementmodel(FEM)withthesoftwareANSYS10.0isestablishedaccordingtotheactualworkingparameters.Withthemodel,thedeformationresultsandstressfieldresultsareanalyzedandthemaximumdisplacementandstressvaluearecalculated,meanwhile,themaximumstresschangewithcrackdepthofsteamturbinediaphragmisanalyzed.Itprovidesagoodfoundationforsolvingtheprobleminproduction.

  • 标签: 蒸汽轮机 裂纹深度 强度分析 膜片 三维有限元模型 有限元分析软件
  • 简介:Thesorption-enhancedsteamreformingprocessofmethanol(SESRP-MeOH)toproducehigh-purityH2wasthermodynamicallyandexperimentallystudied.ThermodynamiccalculationsshowedthatataCO2adsorptionratioof95%,productgascontains98.36%H2,32.8ppmCOundertemperatureof130°Candsteam-to-methanol(S/M)molarratioof2.However,withoutadsorption-enhanced,theproductgascontainsnearly74.99%H2with24.96%CO2and525ppmCO.Toverifythethermodynamiccalculationresults,experimentswereperformedinafixed-bedreactorloadedwithcommercialCuO/ZnO/Al2O3methanolreformingcatalystand22%K2CO3-promotedhydrotalciteasCO2adsorbent.Experimentalresultsshowedthat99.61%H2couldbeobtainedbySESRP-MeOHatreactiontemperatureof230°CandS/Mof2.UnderthesameCH3OHconversion,thereactiontemperaturedecreasedbyalmost50°CandH2concentrationincreasedofmorethan20%usingSESRP-MeOHcomparedwithsolelysteamreformingofmethanol.Thecharacterizationoftheadsorbentandcatalystshowedthattheadsorbentshowedgoodstabilitywhilethecatalystwasseriouslysinteredunderthehighregenerationtemperatureoftheadsorbent.

  • 标签: 甲醇水蒸气重整 蒸汽重整 吸附率 纯度 生产 氢气
  • 简介:Thesteamreformingoffourbio-oilmodelcompounds(aceticacid,ethanol,acetoneandphenol)wasinvestigatedoverNi-basedcatalystssupportedonAl2O3modifiedbyMg,CeorCointhispaper.Theactivationprocesscanimprovethecatalyticactivitywiththechangeofhigh-valenceNi(Ni2O3,NiO)tolow-valenceNi(Ni,NiO).Amongthesecatalystsafteractivation,theCe-Ni/Cocatalystshowedthebestcatalyticactivityforthesteamreformingofallthefourmodelcompounds.Afterlong-termexperimentat700°CandtheS/Cratioof9,theCe-Ni/Cocatalyststillmaintainedexcellentstabilityforthesteamreformingofthesimulatedbio-oil(mixedbythefourcompoundswiththeequalmasses).WithCaOcalcinatedfromcalciumacetateasCO2sorbent,thecatalyticsteamreformingexperimentcombinedwithcontinuousinsituCO2adsorptionwasperformed.WiththecomparisonofthecasewithouttheaddingofCO2sorbent,thehydrogenconcentrationwasdramaticallyimprovedfrom74.8%to92.3%,withtheCO2concentrationobviouslydecreasedfrom19.90%to1.88%.

  • 标签: 镍基催化剂 水蒸汽重整 模型化合物 生物油 NI基催化剂 转化
  • 简介:近些年来兴起的开源系统和创客运动,引发了制造技术的革命。在第三次工业革命新浪潮影响下,3D打印等数字桌面制造工具成为全球各领域关注的焦点。作为一种快速成型技术,3D打印是蕴含“设计思维”的个性化创造工具,可以塑造可重用的多态教育对象,打造虚实结合的教育应用服务创新平台,促进基于创造的学习。当前有代表性的3D打印教育创新应用项目,主要集中在创客空间、创新实验室和STEAM课程中。3D打印教育创新应用体系应不断优化3D打印技术实现,完善3D打印教育服务支持体系,在创新理论不断演进与更新中,丰富基于创造的学习样态,拓展基于创造的学习存在形式,使3D打印从象牙塔里的高科技发展,成为融入学校、家庭和社会教育常态的具有革命性影响的技术,成为技术支持教育应用创新不可或缺的元素。

  • 标签: 3D打印 创客空间 创新实验室 STEAM 教育创新
  • 简介:这份报纸的目的是在设计下面并且离开设计条件改进最后阶段汽轮机和一台600MW蒸气汽轮机的exhaust兜帽的空气动力学的表演。在操作期间,在汽轮机和exhaust兜帽之间的强壮的流动相互作用在兜帽在流动行为上强加影响并且导致汽轮机的不能令人满意的空气动力学的表演并且用尽兜帽。exhaust兜帽因此有潜力以空气动力学的效率被改善。就在汽轮机和exhaust兜帽之间的流动相互作用而言,更弥漫的结束墙的侧面被优化。联合模型汽轮机和模型用尽兜帽计算和实验被执行验证优化的效果。模型实验证明设计修正导致了全面压力恢复系数的实质的增加。流动和空气动力学的表演照原尺寸最后一台阶段汽轮机并且照原尺寸用尽兜帽被模仿探索流动物理改变到更弥漫的几何学的修正。湿蒸气作为流动媒介被选择。在不同操作条件下面的实际流动地被分析。

  • 标签: 非设计工况 气动特性 600MW汽轮机 空气动力性能 空气动力学性能 压力恢复系数
  • 简介:Forsyngasproduction,thecombustionoffossilfuelsproduceslargeamountsofCO2asagreenhousegasannuallywhichintensifiesglobalwarming.Inthisstudy,chemicalloopingcombustion(CLC)hasbeenutilizedfortheeliminationofCO2emissiontoatmosphereduringsimultaneoussyngasproductionwithdifferentH2/COratioinsteamreformingofmethane(SR)anddryreformingofmethane(DR)inaCLC-SR-DRconfiguration.InCLC-SR-DRwith184reformertubes(similartoanindustrialscalesteamreformerinZagrosPetrochemicalCompany,Assaluyeh,Iran),DRreactionoccursoverRh-basedcatalystsin31tubes.Also,SRreactionishappenedoverNi-basedcatalystsin153tubes.CLCviaemploymentofMn-basedoxygencarrierssuppliesheatforDRandSRreactionsandproducesCO2andH2Oasrawmaterialssimultaneously.AsteadystateheterogeneouscatalyticreactionmodelisappliedtoanalyzetheperformanceandapplicabilityoftheproposedCLC-SR-DRconfiguration.Simulationresultsshowthatcombustionefficiencyreached1attheoutletoffuelreactor(FR).Therefore,pureCO2andH2OcanberecycledtoDRandSRsides,respectively.Also,CH4conversionreached0.2803and0.7275attheoutletofSRandDRsides,respectively.Simulationresultsindicatethat,3223kmolh-1syngaswithaH2/COratioequalto9.826wasproducedinSRsideofCLC-SR-DR.Afterthat,1844kmolh-1syngaswithaH2/COratioequalto0.986wasachievedinDRsideofCLC-SR-DR.ResultsillustratethatbyincreasingthenumberofDRtubesto50tubesandconsidering184fixedtotaltubesinCLC-SR-DR,CH4conversionsinSRandDRsidesdecreased2.69%and3.31%,respectively.However,thissubjectcausedtotalsyngasproductioninSRandDRsides(inallof184tubes)enhanceto5427kmolh-1.Finally,thermalandmolarbehaviorsoftheproposedconfigurationdemonstratethatCLC-SR-DRisapplicableforsimultaneoussyngasproductionwithhighandlowH2/COratiosinanenvironmentalfriendlyprocess.

  • 标签: 甲烷重整 蒸汽重整 合成气 CO2 CLC 生产