学科分类
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12 个结果
  • 简介:Thisworkinvestigatestheflowofathirdgradefluidinarotatingframeofreference.Thefluidisincompressibleandmagnetohydrodynamic(MHD).Theflowisboundedbetweentwoporousplates,thelowerofwhichisshrinkinglinearly.Mathematicalmodellingoftheconsideredflowleadstoanonlinearproblem.Thesolutionofthisnonlinearproblemiscomputedbythehomotopyanalysismethod(HAM).Graphsarepresentedtodemonstratetheeffectofseveralemergingparameters,whichclearlydescribetheflowcharacteristics.

  • 标签: 力学 流体力学 管道流体力学 研究
  • 简介:Anovelintermediatefluidvaporization(IFV)technologyforLNGre-gasificationprocesswithspiral-woundheatexchangingtubesisproposed.ThenewIFVprojectcombinestheadvantageofrunningtheshellandtubeheatexchangersathighpressurewiththeadvantageofcompactspaceofheatexchangers.Thermalanalysisonthetwoprocessesofforcedconvectionandvaporizationtypeheattransferinthespiralwoundtubesandvaporcondensation/re-boilingtypeofheattransferviaintermediatefluidinshellsideshowsthefeasibilityofthispromisingtechnology.

  • 标签: 热流体 汽化器 缠绕管 管壳式换热器 气化过程 热交换管
  • 简介:在这份报纸,蒸汽吃惊前面的思考现象(前面的双方在蒸汽阶段)在货车derWaals,液体被考虑。1-dimensional案例和多维的案例被调查。作者发现在某些条件下面,反映的波浪能是单个震动,或一个单身者亚声的阶段边界,或和一条亚声的阶段边界的一弱震动,它取决于事件吃惊的力量。这由于在1989的陈与在一个煤气的动态系统的吃惊前面的思考的已知的结果不同。

  • 标签: 波阵面 流体 反射现象 冲击强度 动力系统 相边界
  • 简介:Fluid-particleinteractionunderpinsimportantbehaviorofgranularmedia.Particle-scalesimulationmayhelptoprovidekeymicroscopicinformationgoverningtheinteractionandofferbetterunderstandingofgranularmediaasawhole.Thispaperpresentsacoupledcomputationalfluiddynamicsanddiscreteelementmethod(CFD-DEM)approachforthispurpose.ThegranularparticlesystemismodeledbyDEM,whilethefluidflowissimulatedbysolvingthelocallyaveragedNavier-StokesequationwithCFD.ThecouplingisconsideredbyexchangingsuchinteractionforcesasdragforceandbuoyancyforcebetweentheDEMandCFD.Theapproachisbenchmarkedbytwoclassicgeomechanicsproblemsforwhichanalyticalsolutionsareavailable,andisfurtherappliedtothepredictionofsandheapformationinwaterthroughhopperflow.Itisdemonstratedthatthekeycharacteristicofgranularmaterialsinteractingwithporewatercanbesuccessfullycapturedbytheproposedmethod.

  • 标签: 粒子相互作用 计算流体力学 颗粒状物料 颗粒介质 数值模拟 NAVIER-STOKES方程
  • 简介:Thisinvestigationdealswiththeeffectsofslip,magneticfield,andnonNewtonianflowparametersontheflowandheattransferofanincompressible,electricallyconductingfourth-gradefluidpastaninfiniteporousplate.Theheattransferanalysisiscarriedoutfortwoheatingprocesses.Thesystemofhighlynon-lineardifferentialequationsissolvedbytheshootingmethodwiththefourth-orderRunge-Kuttamethodformoderatevaluesoftheparameters.TheeffectiveBroydentechniqueisadoptedinordertoimprovetheinitialguessesandtosatisfytheboundaryconditionsatinfinity.Anexceptionalcross-overisobtainedinthevelocityprofileinthepresenceofslip.Thefourth-gradefluidparameterisfoundtoincreasethemomentumboundarylayerthickness,whereastheslipparametersubstantiallydecreasesit.Similarly,thenon-Newtonianfluidparametersandthesliphaveoppositeeffectsonthethermalboundarylayerthickness.

  • 标签: 力学 电磁流体力学 研究 物理理论
  • 简介:在这份报纸,我们以光线参数导出SS波浪思考系数和S波浪光线橡皮阻抗(SREI)的表示的近似。SREI能被S波浪发生角度或P波浪思考角度表示,分别地叫作SREIS和SREIP。我们用从真实木头大小导出的有弹性的模型的学习证明SREIP比SREIS和常规S波浪为岩性学和液体辨别有更好的能力橡皮阻抗(SEI)。我们从Castagna和史密斯(1994)用25组样品评估SREIP可行性。每个样品组被使用页岩构造,盐水沙,并且煤气沙。理论评估也显示全体的那SREIP事件角度比常规液体指示物对液体更敏感。真实地震数据申请也显示出角度计算了高效地使用P波浪和S波浪阻抗罐头的全体的那SREIP描绘紧密煤气沙。

  • 标签: 流体识别 弹性阻抗 波射线 岩性 SMITH 弹性模型
  • 简介:在这份报纸,有变化时间的内部液体的一个灵活海洋的起床人的颤动减小被使用边界控制方法和Lyapunovs直接方法学习。完成更精确、实际的起床人动态行为,有变化时间的内部液体的海洋的起床人的模型被一个分布式的参数系统(DPS)与部分微分方程(PDE)和包含空间和时间的函数的平常的微分方程(颂诗)建模。如果变化时间的内部液体被考虑,起床人的动态回答是完全不同的。边界控制基于PDE建模的原来的无限的维数和Lyapunovs直接方法在起床人的最高的边界被设计减少起床人颤动。一致固定和靠近环的稳定性基于建议边界控制被证明。模拟结果验证建议边界控制的有效性。

  • 标签: 边界控制 内部流体 海洋立管 动力学建模 柔性 李雅普诺夫直接方法
  • 简介:Astochasticsimulationoffluidflowinporousmediausingacomplexvariableexpressionmethod(SFCM)ispresentedinthispaper.Hydraulicconductivityisconsideredasarandomvariableandisthenexpressedincomplexvariableform,therealpartofwhichisadeterministicvalueandtheimaginarypartisavariablevalue.ThestochasticseepageflowissimulatedwiththeSFCMandiscomparedwiththeresultscalculatedwiththeMonteCarlostochasticfiniteelementmethod.InusingtheMonteCarlomethodtosimulatethestochasticseepageflowfield,thehydraulicconductivityisassumedinthreedifferentprobabilitydistributionsusingrandomsamplingmethod.Theobtainedseepageflowfieldisexaminedthroughskewnessanalysis,andtheskeweddistributionprobabilitydensityfunctionisgiven.TheheadmodevalueandtheheadcomprehensivestandarddeviationareusedtorepresentthestatisticsofcalculationresultsobtainedbytheMonteCarlomethod.ThestochasticseepageflowfieldsimulatedbytheSFCMisconfirmedtobesimilartothatgivenbytheMonteCarlomethodfromnumericalaspects.TherangeofcoefficientofvariationofhydraulicconductivityinSFCMislargerthanusedpreviouslyinstochasticseepageflowfieldsimulations,andthecomputationtimeisshort.TheresultsprovedthattheSFCMisaconvenientcalculatingmethodforsolvingthecomplexproblems.

  • 标签: 随机模拟 表达方法 流体流动 多孔介质 蒙特卡罗方法 水力传导系数
  • 简介:Astudyispresentedformagnetohydrodynamics(MHD)flowandheattransfercharacteristicsofaviscousincompressibleelectricallyconductingmicropolarfluidinachannelwithstretchingwalls.ThemicropolarmodelintroducedbyEringenisusedtodescribetheworkingfluid.Thetransformedselfsimilarordinarydiferentialequationstogetherwiththeassociatedboundaryconditionsaresolvednumericallybyanalgorithmbasedonquasi-linearizationandmultileveldiscretization.Theefectsofsomephysicalparametersontheflowandheattransferarediscussedandpresentedthroughtablesandgraphs.Thepresentinvestigationsmaybebeneficialintheflowandthermalcontrolofpolymericprocessing.

  • 标签: 流体流动 热通道 伸展 墙壁 MHD 牛顿
  • 简介:Thecochleaisanimportantstructureinthehearingsystemofhumanity.Itsuniquestructureenablesthesensibilitytothesoundwavesofvariedfrequencies.ThewidelyacceptedmodelofthecochleaisexpressedasalongtubelongitudinallydividedbyamembranenamedtheBasilarMembrane(BM),intotwofluid-filledchannels.Basedonvariousassumptionsforthecochlearfluidandstructure,simplifiedmathematicalandmechanicalcochlearmodelsweredevelopedtohelptounderstandthemechanismofthecomplexcoupledsysteminthepastdecades.ThispaperproposesahydrodynamicnumericalcochlearmodelwithconsiderationoftheFluid-StructureInteraction(FSI).Inthismodel,thecochlearlymphisconsideredasinaNewtonianviscousfluid,andthebasilarmembraneismodeledasacompositestructure.Thetravelingwaveissimulated.Alsofocusingonthepressureinthefluidfield,theresultsarecomparedwithstudiesofPetersonandBogert,whereitwasassumedthattheslowcompressivewavesaretravelingalongtheBM.Furthermore,thetransmittingtimeofthecochleartravelingwaveisalsodiscussed.

  • 标签: 流体结构相互作用 耳蜗模型 动力学建模 数值模拟 行波 人类听觉系统
  • 简介:Analyticalsolutionsfortheflexural-gravitywaveresistancesduetoalinesourcesteadilymovingonthesurfaceofaninfinitelydeepfluidareinvestigatedwithintheframeworkofthelinearpotentialtheory.Thehomogenousfluid,coveredbyathinelasticplate,isassumedtobeincompressibleandinviscid,andthemotiontobeirrotational.ThesolutioninintegralformforthewaveresistanceisobtainedbymeansoftheFouriertransformandtheexplicitlyanalyticalsolutionsarederivedwiththeaidoftheresiduetheorem.Thedispersionrelationshowsthatthereisaminimalphasespeedcmin,athresholdfortheexistenceofthewaveresistance.NowaveisgeneratedwhenthemovingspeedofthesourceVislessthancminwhilethewaveresistancesfirstlyincreasetotheirpeakvaluesandthendecreasewhenVcmin.Theeffectsoftheflexuralrigidityandtheinertiaoftheplatearestudied.

  • 标签: 弹性薄板 深部流体 移动速度 弯曲波 重力波 电阻