学科分类
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214 个结果
  • 简介:在多孔的媒介和液体之间的热和集体转移是一个复杂联合过程,它广泛地在设计应用的各种各样的地里被使用,特别为在油和煤气的抽取的自然、人工的破裂。在这研究,一个新方法被建议在破裂处理流动和稳定的流动的热转移问题。在破裂的液体流动用象Mohais的一样的方法被描述,与多孔的墙,和不安方法把破裂看作了一条隧道的人,被用来解决数学模型。不同于以前的研究,shear跳Ochoa-Tapia和Whitaker建议的边界状况在在液体和多孔的媒介之间的接口被使用。主要方法是不安分析和申请砍跳边界条件。渗透的影响,隧道宽度,砍跳在隧道的流动和热转移上的度和有效动态粘性被分析分析答案学习。在有典型参数和热转移的敏感的变化的隧道的轴的速度的分发被获得。

  • 标签: 多孔介质 人工裂缝 流动传热 二维流动 模拟分析 通道宽度
  • 简介:Inthepresentpaper,atheoreticalmodelisproposedtoanalyzethetransientbehaviorofsuppressionofrotatingstallinaxialcompressionsystemsthroughtheuseofanadditionaldistubance,Thegoverningequationsofthemodelareasetofsimultaneousnonlinearfirstorderpartialdifferentialequations,andfornumericalcalculations,asimpleexplicittimemarchingmethodcanbeused.Theinfluenceofsystemparametersonthesuppressioneffectivenessandtheinteractionbetweenrotatingstallandsurgehavebeendiscussedinitially.TheanslysisoftheinfluenceofsystemparameterspresentsthatboththeBparameterandaxisymmetriccomprssorcharacteristichavesignificanteffectonthestabilizationeffectivenessofacontrolstrategy.TheeffectivenessdecreasesasthevalueofBandthenumberofstagesorstageloadingofthecompressorincrease,Ithasbeenfoundthattheonsetflowrateofrotatingstallandsurgeinacompressionsystemmaybedifferent,andthereisastronginteractionbetweenthesetwokindsofinstabilities.TheonsetflowrateofpureonedimensionalsurgedependsonthevalueofBandaxisymmetriccompressorcharacteristic,besidestheslopeofthecompressorcharacteristic.Insomecases,whenrotatingstallwhichisthenaturalmodeofinstabilityinacompressionsystemissuppressedonedimensionalsurgecanoccur,Itoftenlimitstheeffectivenessofacontrolstrategytosuppressrotatingstall.Butwhensurgeisintiatedbyratatingstall,itisalsopossibletoinhibittheoccurrenceofsurgebysuppressingrotatingstallinacompressionsystem.

  • 标签: 透平机 压缩系统 数字模拟
  • 简介:ThispaperstudiesRabinovitch'scompressionexperimentsongraniteandchalkandproposesanoscillatingdipolemodeltoanalyseandsimulatetheelectromagneticradiationphenomenoncausedbyfractureofrocks.Ourmodelassumesthattheelectromagneticradiationpulsesareinitiatedbyvibrationsofthechargedrockgrainsonthetipsofthecrack.Thevibrationsoftherockgrainsarestimulatedbythepulsesofthecracks.OursimulationsshowcomparableresultswithRabinovitch'scompressionexperiments.Fromthesimulationresults,itverifiesanassumptionthatthecrackwidthisinverselyproportionaltothecircularfrequencyelectromagneticradiation,whichispresentedbyRabinovitchetal.Thesimulationresultsalsoimplythat,byusingouroscillatingdipolemodeltogetherwithRabinovitch'stwoequationsaboutthecracklengthandcrackwidth,wecanquantitativelyanalyseandsimulatetheelectromagneticradiationphenomenon,whichisinducedfromthefractureoftherocks.

  • 标签: 高频电磁辐射 岩石断裂 数值分析法 裂缝宽度计算 振荡偶极子 模拟显示
  • 简介:吸收材料(静态存储器)的一架新奇结构的雷达,给正常树脂底composites新功能,被准备。静态存储器的动态压缩测试借助于裂口Hopkinson压力酒吧(SHPB)在在里面飞机和composites的正常方向被执行。在沿着在里面飞机方向的压缩测试,失败发生在在纤维和矩阵之间的接口。一个破裂模式和机制被建议解释这些结果。吸收粒子的增加导致压缩性质的恶化。然而,有吸收性质的雷达的静态存储器的压缩力量上没有明显的减少。

  • 标签: 动力反应 断裂机理 雷达 吸收材料
  • 简介:Hydrogenembrittlementisoneofthekeyissuesforthevanadiumalloysforfusionapplication.PreviousstudyhasshownthatV4TialloyhadbetterpropertiesagainsttheembrittlementthanV4Cr4TiandV4Ti3A1alloys.Itwasthoughtthatthebetterpropertywasbenefitedfromthesmallratioofitsyieldstrengthoveritsultimatetensilestrength.

  • 标签: 钒合金 氢脆变 钛合金 断裂装置
  • 简介:AnewmethodisproposedtocalculatetheGrüneisenparameterdirectlyfromtheexperimentalHugoniotdata,withoutanyassumptiononthelatticevibrationalmodeofthematerialbeingstudied.Comparedwiththeresultscalculatedbythemethodsproposedpreviously,thevaluesoftheGrüneisenparametercalculatedhavethreedistinguishablefeaturesthatsupporttherationalityofthemethod.Anewphenomenonthatthelatticevibrationalmodechangeswiththethermodynamicstateofthesolidhasbeenfirstobservedfromthecalculatedresults,whichimpliesthatthematerialparameterg,characterizingthelatticevibrationalmode,ismaterialdependentratherthanamaterialconstant.

  • 标签: 固体 压缩 Grüneisen方程
  • 简介:Thefastturnoverofsoftwaretechnologies,inparticularinthedomainofinteractivity(coveringuserinterfaceandvisualisation)makesitdifficultforasmallgroupofpeopletoproducecompleteandpolishedsoftware-toolsbeforetheunderlyingtechnologiesmakethemobsolete.AttheHepVis'99workshop,aworkinggrouphasbeenformedtoimprovetherpoductionofsoftwaretoolsfordataanalysisinHENP.Besidepromotingadistributeddevelopmentorganisation,onegoalofthegroupistosystematicallydesignasetofabstractinterfacesbasedonusingmodernOOanalysisandOOdesigntechniques.Aninitialdomainanalysishascomeupwithseveralcategories(componets)foundintypicaldataanalysistools:historams,Ntuples,Functions,Vectors,Fitter,Plotter,AnalyzerandController,SpecialEmphasiswasputonreducingthecouplingsbetweenthecategoriestoaminimum,thusoptimisingre-useandmaintainabilityofanycomponentindividually.TheinterfaceshavebeendefinedinJavaandC++andimplementationsexistintheformoflibrariesandtoolsusingC++(Anaphe/Lizard,Openscientist)andJava(JavaAnalysisStudio),AspecialimplementationaimsataccessingtheJavaLiraries(throughtheirAbstractInterfaces)fromC++.ThispapergiveranoverviewofthearchitectureanddesignofthevariouscomponentsfordataanalysisasdiscussedinAIDA.

  • 标签: 软件开发 数据分析 数据分析工具 HENP
  • 简介:The5MWlowtemperaturenuclearheatingreactor(NHR-5)isanewandadvancedtypeofnuclearreactordevelopedbyInstituteofNuclearEnergyTechnology(INET)ofTisinghuanUniversityofCHinain1989,Itsmainloopisathermal-hydraulicsystemwithnaturalcirculation.ThispaperstudiesthesafetyofNHRundertheconditionofloss-of-coolantaccidents(LOCAs)bymeansofsimulantexperiments.First,theBackgroundandnecessityoftheexperimentsarepresented.thentheexperimentalsystem,includingthethermal-hydraulicsystemandthedatacollectionsystem,andsimilaritycriteriaareintroduced.Uptonow,thedischargeexperimentswiththeresidualheatingpower(20%ratedheatingpower)havebeencarriedoutontheexperimentalsystem,Thesystemprametersincludingcirculationflowrate,systempressure,systemtemperature,voidfraction,dischargemassandsoonhavebeenrecordedandanalyzed.Basedontheresultsoftheexperiments,theconclusionasareshownasfollos:onthewhole,thereactorissafeundertheconditionofLOCAs,butthethermalvacillationsresultingfromthevibrationofthecirculationflowratearedisadvantageoustotheinternalpartsofthereactorcore.

  • 标签: 核反应堆 安全性 冷却剂 事故
  • 简介:在压缩下面的戒指聚合物刷子的一个纹理粗糙的祷告春天模型的分子的动力学模拟被介绍。灵活聚合物刷子在压缩期间总是是混乱的,而semiflexible聚合物刷子趋于在足够地强壮的压缩下面被订。进一步,semiflexible聚合物刷子的聚合物单体密度在刷子表面附近很高,导致表面附近的免费精力的山峰价值。因此,当nanoparticles在semiflexible戒指聚合物刷子被压缩时,他们趋于展出在刷子表面之间的仔细包装的单个层的结构,刺不进的墙,和伪二维的订的结构接近刷子表面在强壮的压缩下面被形成。这些调查结果提供一条新途径给设计应答的应用。

  • 标签: 聚合物刷 压缩过程 纳米粒子 二维结构 有序结构 半柔性
  • 简介:Spallationtargetrepresentsoneofthemostchallengingcomponentsinacceleratordrivensystems(ADS)sinceitisthecomponentcouplingtheacceleratorandthesub-criticalcore.Itissubjectedtobombardmentofintenseprotonbeamandveryhighthermalloadinastrongradiationfield.TheirradiatedLBEtargetposesseverehandlingproblemsforthemaintenancestaffandotherscientistsduetoitsresidualactivity[1].ToassistthedesignofADS,thegeneralradiologicalsafetyaspectsoflead,lead-bismutheutectic(LBE)andtungstenspallationtargetwerestudiedwithMCNPX2.7code[2].Thespallationtargetwasirradiatedbya250MeV,10mAprotonbeamproducedbyalinearprotonaccelerator.Theneutronyield,neutronspectrum,residualproductionandtimeevolutionfortheirradiatedtargetwereanalyzed.

  • 标签: Designed China ADS