简介:Inthispaper,weconsiderlowerorderrectangularfiniteelementmethodsforthesin-gularlyperturbedStokesproblem.ThemodelproblemreducestoalinearStokesproblemwhentheperturbationparameterislargeanddegeneratestoamixedformulationofPois-son'sequationastheperturbationparametertendstozero.Weproposetwo2Dandtwo3Dnonconformingrectangularfiniteelements,andderiverobustdiscretizationerrorestimates.Numericalexperimentsarecarriedouttoverifythetheoreticalresults.
简介:Inthepresentworktheeffectofthepowerlawexponentofpower-lawfluidandnon-Darcynumberofnon-Darcyflowonstabilityofnaturalconvectioninporousmediaarestudied.Thecomputationanalysisofeffectofpowerlawexponentofpower-lawfluidandnon-Darcynumberofnon-DarcyflowintherectangularductonthetransitionRayleighnumberRa^*,whichmeanstheconvectivemodeltransitingfromstationarystatetoperiodicsolution.Theducthasfilledaporousmediumsaturatedwiththepower-lawnon-NewtonianfluidorNewtonianfluidfornon-Darcyflow,inwhichthereisuniforminternalheatgenerationperunitvolumeq.InthispapertherelationshipbetweenthetransitionRayleighnumberRa^*andthepower-lawexponentn,Ra^*andnon-DarcynumberBe,areshown.tothesetwoaspects,thetransitionroutefromsteadytochaoticcovectionisalsoobtained.
简介:研究Forchheimer系数b在有界区域内,关于粘性流体对接的多孔介质的连续依赖性。假设在Ω1中,粘性流体是缓慢流动的,所控制的方程是Forchheimer方程;在Ω2的多孔介质中,我们假设流体所控制的方程是Darcy方程。首先进行先验假设得到关于u和v的L2范数的界的估计;然后利用杨氏不等式,散度定理还有其他的微分不等式,经过一定的放缩,构造出恰当的辅助函数;最后我们利用Gronwall不等式处理辅助函数,得到解关于Forchheimer系数b的连续依赖性。
简介:Anumericalstudyofanon-Darcymixedconvectiveheatandmasstransferflowoveraverticalsurfaceembeddedinaporousmediumundertheefectsofdoubledispersion,melting,andthermalradiationisinvestigated.Thesetofgoverningboundarylayerequationsandtheboundaryconditionsistransformedintoasetofcouplednonlinearordinarydiferentialequationswiththerelevantboundaryconditions.ThetransformedequationsaresolvednumericallybyusingtheChebyshevpseudospectralmethod.Comparisonsofthepresentresultswiththeexistingresultsintheliteraturearemade,andgoodagreementisfound.Numericalresultsforthevelocity,temperature,concentrationprofiles,andlocalNusseltandSherwoodnumbersarediscussedforvariousvaluesofphysicalparameters.
简介:""Mensaytheyhatetoshop,""saysZhukin,CityUniversityofNewYorkSociology(社会学)professor.""Yetwhenyouaskthemdeeperquestions,itturnsoutthattheyliketoshop.Mengenerallyliketoshopforbooks,musicandhardware.Butifyouaskthemabouttheshoppingtheydoforbooksormusic,they'llsay,'Well,that'snotshopping.That'sresearch.'""
简介:Romanticismisanimportantstageintheevolutionofman’sself-consciousness.Itshowsnewinterestinandnewconcernwithmanandnature.Wordsworthiswell-knownasanaturepoet.Thethemeofhumanmindandnatureinhispoemshaslongattractedreaders’attention.However,hedoesnotindulgeinnatureitselfbuttakesitasconsolationandinspirationforhumankind.Inordertohighlightthepoet’sconcernwithhumanmind,thepresentpaperchoosestoexploreWordsworth’sconcernwithchildren’smind,basedontheanalysisofWordsworth’sThePreludeandmanyofhispoemsaboutchildren.
简介:Sinceancienttimes,asoneofthesymbolsofuglyanddirty,prostitutesareinvariablylivingintheblackmarginsofsociety.Facingprostitutes’miseries,peoplealwayscannotunderstandtheiremotions,mentalitiesanddesires,ortreatsthemasequals,particularlyaswomen.ProstitutesareaspecialgroupintheoppressedwomeninWesternsocieties.MargaretandNanaaretwotypicalimagesoftheminthehistoryofwesternliterature.Withtearsandlives,theydeducetheirmiserablelifestoriessimilarly.