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简介：Theeffectsofheatlossonthestructureoflaminarflamelets,whicharetheconstitutiveelementsofturbulentflamesunderthemostcommonoperatingconditions,areinvestigatedfortypicalaeronauticalgas-turbineoperatingconditionsattake-off.Themagnitudeofheatlossisquantifiedviathe"enthalpydefect"measuredwithrespecttoanadiabaticflame.Aproceduretogeneratelaminarflameletswithanassignedenthalpydefectattheboundariesisdevisedandappliedtononpremixedpropane/airflames,aspropanereproducestheessentialfeaturesofhigherhydrocarboncombustion.Itisfound,contrarytocommonlyheldbeliefs,thattheenthalpydefecthasasignificanteffectontheconcentrationnotonlyofminorspecies,butalsoofmainreactionproducts.Sucheffectsarefoundingeneraltobemorepronouncedforfuel-richconditions.Animpactisanticipatedontheformationrateofnitricoxides.Theeffectsofscalardissipationratearealsodiscussed.

简介：Theoreticalandexperimentalinvestigationsofheattransferinflatcurvilinearchannelhavebeencarriedout.Linearandnon-lineareffectsofDeanvortexesonintensityofheattransferweretakenintoaccount.Thelineareffect,whichdescribeharmonic(sinuous)variationoftheheattransfercoefficientneartheconcavesurfaceofthechannelandthenon-lineareffectcausesthegeneralincreaseoftheheattransfercoefficientduetoaugmentationofheattransferengenderedbytheDeanvortexes.Forbotheffects,mathematicalrelationswereobtainedintheformofquadratures.Thesenumericalresultsweremodifiedtotheformconvenientinengineeringcalculations.TheinvestigationshaveshownthatbothlinearandnonlinearcomponentsgrowupwiththeDeannumber.NonlinearcomponentQ0Tincreasesmoreabruptly,whilethelinearoneQ1Tismoreconservative.Thisisaconfirmationofstabilityofvortexstructures.

简介：Antheoreticalinvestigationwasconductedtodetectthegas-solidinterfaceeffectonlaminarflowcharacteristicsforgasflowingthroughmicropassages.Inthewall-adjacentregion,thechangeinviscosityoffluidvsthedistancefromthewallsurface,asderivedfromthedkinetictheoryofgasesresultinsignificantinfluenceontheflowcharacteristicsinmicropassages.Amodelwasproposedtoaccountforthewalleffect.Analyticalexpressionsforvelocityprofilesandpressuredropwerederived,respectively,forlaminarflowofgasesinmicrotubesandinextremelynarrowparallelplaes.TheKnudsennumber,Kn,asacriterion,thattheflowcanbetreatedreasonablyasflowinmacrochannels,isdiscussed.

简介：Inapreviouspaper,amethodhasbeendevelopedtostudythestabilitycharacteristicsoflaminarboundarylayersovercompliantwalls.Inthispaper,theeffectofdoublelayeredcompliantwallandKramertypecompliantwallondelayingthetransitionisinvestigated,anditisshownthattheredoesexistthepossibilitytode-laythetransitionbyapplyingsuchcompliantwalls.

简介：Thestabilitycharacteristicsoflaminarboundarylayersovercompliantwallswasstudiedbythelineartheory.Unlikethepreviousauthors,thecoupledmotionofthefluidandsolidwasrequiredtosat-isfythecontinuityconditionsofboththevelocityandstressattheinterface.Resultsofcalculationsshowthatasthespeedratioordensityratioexceedsacertainthresholdvalue,thetwotypesofunstablewaveswillnolongerbedistinguishable,andthetangentialcomponentofthedisturbancestressisnolongernegligi-ble.Sotheneglectofit,asthepreviousauthorsdid,isunjustified.

简介：为有intra层和inter-laminar接口的损坏效果的合成把压成薄片的盘子的一个组成的模型被介绍。模型基于一般six-degreesof-freedom板理论，接口上的排水量的断绝被三个形状函数描绘，它根据解决方案被提出令人满意三个平衡方程。由使用变化原则，三维的非线性的平衡与二个不同损坏模型一起的把压成薄片的盘子的微分方程被导出。就有损坏的一个简单地支持的把压成薄片的盘子而言，然后，一个分析答案用有限差别方法被介绍获得inter-laminar压力。

简介：Anumericalsimulationisperformedtofindoutakeyvorticalstructureinthelaminar-turbulenttransition.Alow-speedstreakisgeneratedinsidealaminarboundarylayerusinganisolatedcuboidroughness,aimedatprovidinganenvironmentunstabletoouterdisturbances.Then,ashortdurationjetisissuedintotheboundarylayer.Whenthejetvelocityislow,somevorticesappearintheboundarylayer,butthetransitionoftheboundarylayerdoesnottakeplace.However,whenthejetvelocityexceedsacertainthreshold,twovorticesnewlyappearabovetheelongatedlegsofaV-shapedvortexandonlyoneofthemisstretchedandsurvives.Afterthat,vorticesaregeneratedoneafteranotheraroundthesurvivedone.Bycomparingthedecayedandthesurvivedvortices,itisfoundthatthedifferenceintheirheightsisthekeycharacteristicwhichleadstothetransition.

简介：Temporalmodedirectnumericalsimulationwasdonefortheprocessoflaminar-turbulenttransitioninanincompressibleboundarylayeronaflatplate.Theanalysisoftheresultsshowedthatduringthebreakdownprocessoflaminar-turbulenttransition,themodificationofthemeanflowprofilebythedisturbancesledtoaremarkablechangeinitsstabilitycharacteristics,manifestedinthesignificantenlargementofthelinearunstablezoneandthemaximumamplificationrate,andledtothatmanymoredisturbanceswereexcitedandenhancedrapidly,correspondinglytheturbulentenergyalsoincreasedrapidly,andthemeanflowprofilesevolvedswiftlyfromlaminartoturbulent.Itwasalsofoundthatiftheobliquewavesintheinitialdisturbancesdidnotformsymmetricalpairs,thesubsequentspan-wisemeanvelocitieswould,ingeneral,benonzeroduetononlinearinteraction,whichwouldhaveagreateffectonthestabilitycharacteristicsandalsoimpliedthattheturbulenceobtainedbydirectnumericalsimulationmightnotbefullyarandomprocess.

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简介：AnanalyticalsolutionofvelocityprofilesforNon-Newtonianfluidsdescribedbythepower-lawequationinaxiallaminarflowthrougheccentricannuliispresented.Theexpressionsoflimitvelocitiesandcontoursofequalvelocityareobtained.Themainapproaches,claimedinthispaper,arethatthetermTrz/rinthedifferentialequationofflowandthenon-symmetricalvelocitydistributionaboutthegeometriccenteroftheradialclearanceareconsidered.

简介：Inthepresentpaperitwillbeshownthat,bytakingthereferenceframemovingwiththevelocityoffluidattheinterlaceoftwosteadyparallelstreams,thelaminarboundarylayerflowinthetwofluidscanbedecoupledintotwoflows.Theseareexactlythesameasthelaminarboundarylayerflowsalongaflatplate.Andthat,byusingtheexistingexactsolutionofthelaminarboundarylayerequationfortheboundarylayerflowalongaflatplateandappropriateboundaryconditions.Anexactsolutionofthelaminarboundarylayerequationforthelaminarboundarylayerbetweentwoparallelstreamswithdifferentdensities,viscocitiesandvelocitiesisgivenelegantly.ForthecasesconsideredbyLock,theresultsobtainedbythepresentmethodarecomparedwithLock’snumericalcalculationsindetail.

简介：这研究通过数字模拟在一个圆形的热exchanger试管调查了热转移和一个种swirl发电机的流动特征。这类swirl发电机导致的swirl流动能与最小的压力落下惩罚获得高热转移率。模拟被执行理解这种mesoscale热改进部件的物理行为。由设想热转移和流动特征，swirl流动被导致由，这被发现打漩在圆形的试管的生成器结合侵犯的喷气效果。在通过swirl生成器以后，液体的本地磨擦因素能快速更快速回到底层，当本地Nusselt数字为距离维持更高的值时；因此，本地性能的评估标准被改进。单个因素的优化被用于三个几何参数，即，角度打漩生成器(25o，45o，和60o)，长度打漩发电机(0.005，0.01，和0.02?m)，并且中心杆半径(1，2，并且3?公里)。为在一个圆形的试管的空气的laminar流动的swirl生成器的最佳参数被获得，它应该是60o，0.005?m，并且3?公里分别地。

简介：Analyticalsolutionisobtainedofcoupledlaminarheat-masstransferinatubewithuniformheatflux.Thiscorrespondstothecasewhenalayerofsublimablematerialiscoatedontheinnersurfaceofatubewithitsoutersurfaceheatedbyuniformheatfluxandthiscoatedmaterialwillsublimeasgasflowsthroughtthetube.

简介：这份报纸在Paleogene的Shahejie形成在Dongying消沉在页岩水库上被进行。基于详细核心描述，摇薄节，擦亮的氩离子，扫描电子显微镜学(SEM)分析，CT扫描和碳氧同位素的测试，inter-laminar的形成机制断裂(或缝接)并且他们的发展条件被diagenetic进化特征和水库空间进化特征的全面分析讨论。结果证明在Dongying消沉的把压成薄片的合成模式被把压成薄片的方解石和泥土矿物质的垂直分发统治。形成对照到传统的理解，inter-laminar破裂的发展度低得多。没有框架矿物质，和微缝接是的先存在的很好连接的毛孔或水平过压，在层之间的纯液体不能存在液体移植的有利路径。从inter-laminar破裂起源机制和它的进化的点，所谓的缝接，比那烃代提起了毛孔压力并且导致了平行microfractures的传统的理解是更多建筑群。但是inter-laminar破裂与那有小关系迭合是否被开发或床上用品边界是清楚的。事实上，页岩水库inter-laminar破裂不是严密骨折。他们被先存在控制内部小粒的毛孔(或缝接)或溶解毛孔，散布了碳酸盐薄片边界并且被以后的超级压力连接，溶解和渗出物力量。并且开发条件是埋葬深度(比3000m大)并且Ro值(>0.6%)。它的起源和进化的讨论有重要石油优化水库片断和有利目标区域选择上的地质的意义。

简介：Thecoilingtemperatureofthehotstriprollingprocessplaysanimportantroleinstripqualitycontrol.Thenewly-builtlaminarflowcoolingcontrolsystemwasindependentlydevelopedbyBaosteel.L2conductstotallydynamiccontrol(L1onlyexecutestheresultfromL2,anddoesnotconductanydynamiccontrol).Thesystemhasmanyadvantages,suchasquickreal-timecontrol,accuratemodelcalculation,quickresponseafterself-adaptation,etc.Comparedwiththe2050mmhotstriprollingline,thenewsystemcansatisfythestrictcoolingrequirementsofhighstrengthsteel,siliconsteelandheavyplatesbecauseofitsnewly-developedtechnologiesofcoolingratecontrol,stripcoolingbysectionsandproportion-integral-differentialcoefficient(PID)feedbackfuzzycontrol.

简介：Theclassicalpowerlawnon-Newtonianfluidsenergyboundarylayerequationisprovedimpropertodescribetheself-similarheattransfer.Atheoreticalanalysisformomentumandenergyboundarylayertransferbehaviorismadeandthefullsimilarityheatboundarylayerequationisdeveloped,whichmaybecharacterizedbyapowerlawrelationshipbetweenshearstressandvelocitygradientwiththeFalkner-Skanequationasaspecialcase.Bothanalyticalandnumericalsolutionsarepresentedformomentumandenergyboundarylayerequationsbyusingthesimilaritytransformationandshootingtechniqueandtheassociatedtransfercharacteristicsarediscussed.

简介：边界层转移一个完全倾斜的盘子借助于热转移大小被学习了。一个热流动传感器被开发了，为表面或流动的各种各样的类型转以便测量对流的热的效率。它在经常的温度的操作允许热流动的直接、快的大小。现在的纸报导传感器的发展并且在取决于外部流动的入射角的边界层介绍它的应用程序给转变的学习。在批评雷纳兹数字和压力坡度参数之间的一种指数的关系被发现了。

简介：Heattransferintheevacuatedcollectortubeisathree-dimensionallaminarnaturalconvectionproblemdrivenbybuoyancy.Becauseofitscomplexity,noeffectivetheoreticalmodelisavailabledespiteoflimitedexperimentalworkwhichisconfinedtooneaspect.Thepresentworkaimstodepicttheconvectiveheattransferinsideatwo-endedinclinedtubewithEast-Westsymmetricheatinputusingnumericalmethods,Basedonreasonableassumptions,governingequationsoftheinsidefluidareestablished.Thecorrespondingdiscretizatedequationsaresolvedbyemplogyingnumericalmetholds.Thecalculatedresultsaredisplayedforvelocityandtemperatureprofilesondifferentcross-sectionalplasnes.whichpresenttheflowpatterncharacterizedbyupflowanddownflowalongtheaxialdirectionandadherentflowalongtheperipheraldirection,andtheheattransferrpocessfromthewalltothecenter,Furthermore,thetransientNusseltnumberandaveragetemperaturelevelareshownanddiscussed.Finally,theparametriceffectsofthetuberadiusandtheheatinputontheflowandheattransferarealsogiven.

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