学科分类
/ 10
200 个结果
  • 简介:基于连续统的有限变丑理论和poroelastic理论,为在自然、起始的坐标的浸透液体的多孔的媒介(FSPM)的acoustoelastic理论被开发在波浪速度上调查有效压力和液体毛孔压力的影响。第一,在FSPM的大部分静态的变丑前上附加的一个小动态运动的假设产出自然、起始、最后的配置,谁的排水量,紧张,和压力稳固骨骼并且在一个FSPM粒子的液体能分别地在自然、起始的坐标被描述。第二,从运动和FSPM的非线性的组成的关系的介绍的最后状态的方程的平衡的起始状态的方程的减法为小动态运动导致运动的方程。第三,同类的变丑前的考虑和小动态运动的飞机泛音形式给一个acoustoelastic方程,它为快纵的波浪的关系提供分析明确的表达,快砍波浪,慢砍波浪,并且有稳固骨骼的压力和液体毛孔压力的慢纵的波浪。最后,在靠近毛孔的jacketed条件,开毛孔的jacketed条件,传统的unjacketed条件,和triaxial状况下面的各向同性的FSPM作为一个例子被拿讨论速度快并且慢砍沿着起始的主要稳固骨骼的紧张之一的方向宣传的波浪。详细讨论证明FSPM的波浪速度被有效压力和液体毛孔压力通常影响。仅仅,液体毛孔压力在FSPM的波浪速度上有小效果应用起始的主管的部件稳固骨骼强调或紧张是相等的,它与以前的试验性的结果一致。

  • 标签: 孔隙流体压力 饱和多孔介质 弹性理论 有限变形理论 运动叠加 状态方程
  • 简介:ThespeciationanddistributionofGd(Ⅲ)inhumaninterstitialfluidwasstudiedbycomputersimulation,Meantimeartificialneuralnetworkwasappliedtotheestimationoflogβvaluesofcomplexes,Theresultsshowthattheprecipitatespecies,GdPO4andGd2(CO3)3,arethepredominantspecies.Amongsolublespecies,thefreeGd(Ⅲ)[Gd(HSA)],[Gd(OX)]andthentheternarycomplexesofGd(Ⅲ)withcirtratearemainspeciesand[Gd3(OH)4]becomesthepredominantspeciesattheGd(Ⅲ)totalconcentrationof2.2×10^-2mol/L.

  • 标签: 计算机模拟 钆(Ⅲ) 表面物种形式 人体 细胞液 神经网络
  • 简介:装载液体的薄面板的吸收器的健全吸收被调查。一个一般理论和一个近似理论被给。势能动能的参数,和装载液体的因素被建议。这使吸收机制更清楚,并且比以前简单的计算。薄面板的吸收器的吸收系数和阻抗与一个水疗院听觉的试管被测试。试验性的结果与理论结果同意了很好。

  • 标签: 声音 吸收装置 吸收剂 吸收系数 阻抗
  • 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:Theinertiasofthefluidandtheinnercylinderincoaxialcylinderrheometer(CACR)havegreatinfluenceontheunsteadyflowofnon-Newtonianfluid.EvenfortheNewtonianfluidthereexistthesocalled'stressovershoot'phenomenon.Inthepresentarticlethisphenomenonwasstudiedindetailandamethodcorrectingthemeasuredresultsforanunsteadyflowintherheometerwasproposed.Itisfoundthattheinertiaeffectofthefluidcanbeignoredwhenthegapbetweencylindersissmall.

  • 标签: INERTIA RHEOMETER FLUID HEMORHEOLOGY
  • 简介:ThispaperstudiesRayleigh-B'enardconvectionofmicropolarfluidlayerheatedfrombelowwithrealisticboundaryconditions.AspecificapproachforstabilityanalysisofaconvectiveproblembasedonvariationalprincipleisappliedtocharacterizetheRayleighnumberforquitegeneralnatureofboundingsurfaces.TheanalysisconsistsofreplacingthesetoffieldequationsbyavariationalprincipleandtheexpressionsforRayleighnumberarethenobtainedbyusingtrialfunctionsatisfyingtheessential...

  • 标签:
  • 简介:TheconstitutiveequationforasemiconcentratedfibresuspensionintheOldroyd-Bfluidhasbeenderivedfromastatisticalmodelofsuchasuspensionbyemployingthemoleculartheoryforpolymericliquids.Tocircumventtheoreticaldifficultiesinviscoelasticfluidmechanics,severalsimplifiedmodelsareusedtoaccountfortheinteractionsoffibresandpolymermolecules.Someofmaterialfunctionsarecalculatedintermsoftheconstitutiveequation.

  • 标签: SUSPENSION CONSTITUTIVE equation material FUNCTIONS phase
  • 简介:为在一个三维的围住的领域的不可压缩的二进制液体混合物的进化的二个不同模型被考虑。他们由3D组成不可压缩的海军司烧方程,使外部力量遭到到时间依赖者并且结合了一个对流Allen-Cahn或Cahn-Hilliard方程。如此的系统能被看作海军司烧方程的归纳到二阶段的液体。用轨道途径,作者为两个系统证明轨道引起注意的人的存在。

  • 标签: 流体混合物 三维轨迹 吸引子 STOKES方程 二元 不可压缩
  • 简介:Hydrodynamicandthermalcharacteristicsinapipewithsinusoidalwavysurfaceforsteadylaminarflowareinvestigatednumericallyinthepresentstudy.TheintegralformsofgoverningequationsarediscretizedusingcontrolvolumebasedFinitevolumemethodwithcollocatedvariablearrangement.SIMPLEalgorithmisusedandTDMAsolverisappliedforsolutionofsystemofequations.Apipeoflengthequalto4λisconsidered.Effectofsurfacewaviness,determinedbywavelength-amplituderatioλ/a(=L^*),onflowandthermalfieldispresented.ThesimulationworkhasbeencarriedoutforL^*=11.0-30.0foraReynoldsnumberrange50to2000.Resultsarepresentedintheformofstreamfunction,isothermallines,velocityandvorticityprofiles,changeofmeanfrictionfactor,variationinskinfriction,localandaverageNusseltnumberwithReynoldsnumber,wavenumber(n)andL^*.Foraparticulargeometry,lengthofcirculationzoneincreaseswithreynoldsnumberandapproachesalimitingvalueforhigherReynoldsnumber.Wallshearstressinthebulgepartofthechannelshowssmallervaluesthataffectlargely.therateofheattransferandNusseltnumbershowsminimumvaluesinthisregion.Thiscirculationzonedrasticallyincreaseswiththeincreaseofsurfacewavinessshowinghighmeanfrictionfactorperwavelength.MeanfrictionfactorinverselyvarieswithReynoldsnumber.Acorrelationisproposedforcalculatingfrictionfactorintheformf=C/(Re)^m,where‘C’and‘m’representstwopolynomialsofdegree4and2respectivelyandarefunctionofL^*.Higherwavinessofthesurfaceshowsthehigherheattransferratethanlowerwaviness.Heattransferratefallsalmostexponentiallyalongtheaxialdirectionwiththeincreaseofwavenumber.

  • 标签: 流体 波形管 热交换 特征
  • 简介:ResearcheffortsmadesofartosimulatefibresuspensionflowsarelimitedtofibresuspensionsinNewtonianfluids.Thoughshortfibrecompositesaremostlymadeofpolymers,lackofsuitableconstitutiveequationsforfibresuspensionsinviscoelasticfluidsfrustratesattemptstosimulateflowsofthesesuspensions.ApreliminaryworkdonebytheauthorledtoaconstitutiveequationforsemiconcentratedfibresuspensionsintheOldroyd-Bfluid.Thispaperdescribesthemathematicalformulationoftheflowproblemsforsuchasuspensionandthenumericalproceduretosolvethem.Somenumericalresultsofflowpastasphereinatubearealsopresented.

  • 标签: suspension finite element METHOD TIME-DEPENDENT METHOD
  • 简介:Inthispaper,effectsonofsixtypeofresinsthedecolorizationofD-ribosezymoticfluidhavebeenstudiedforthefirsttime.TheresultsshowthatresinNKA-IIhasthebesteffect.thedecolorizationrageofD-ribosezymoticfluidis91%atvelocityof1.0BV/hrand25℃,theadsorptioncapacitycanreachupto5.7BV.Theeffectsofadsorptionconditionsaswellasconditionsofresinregenerationontheresindecolorizationcapabilitywerealsostudied.

  • 标签: D-核糖 脱色 树脂吸附
  • 简介:Hydrotalcitecanactasaco-stabilizerwithothermainstabilizerforpoly(vinylchloride)(PVC).ThethermalstabilityandfluidpropertyofPVCfilledwithhydrotalcitesurface-treatedwithtitanateandsilanewerestudiedinthiswork.OrganicSnisamainstabilizerandhydrotalciteisastabilizingassistant.ThestabilityofthePVCresinmixedwithorganicSnandhydrotalciteisbetterthanthatofthePVCresinmixedwithorganicSnalone.ItisshownthatthePVCresinfilledwithhydrotalcitepossessesabetterstaticanddynamicheatstability.Moreover,hydrotalcitecanimprovethefluidpropertyofPVC,whichisadvantageoustotheprocessingofPVC,andtheoptimumcontentofhydrotalciteisabout1%-2%(massfraction).

  • 标签: Hydrotalcite PVC Thermal stability FLUID PROPERTY
  • 简介:EffectsoftheorientationandapexangleonthesettlingvelocityofconicalparticlesinBinghamplas-ticfluidsarenumericallyinvestigatedoveraReynoldsnumberrangeof1≤Re≤100,Binghamnumberrangeof0≤Bn≤100,andconeanglerangeof20≤α≤150°.Governingequations(ofcontinuityandmomentum)aresolvednumericallyusingthefiniteelementmethodtoobtainvelocityandpressurefieldsthatarepostprocessedtoobtainvaluesofthedragcoefficien.Futthermore,theeffectofconeori-entationontheflowfieldisvisualizedandexploredintermsofstreamlinecontoursandthemorphologyofyielded/unyieldedregions.Finally,theobtainedvaluesofdragarecorrelatedviaasimplepredictiveexpressionintermsofthemodifiedReynoldsnumber.Theeffectoftheconeangleondragisfoundtobemoderatebecausethedragforceactingonthelateralsurfaceisasmallfractionoftheoveralldrag.

  • 标签: BINGHAM NUMBER REYNOLDS NUMBER Yielded/unyielded REGIONS
  • 简介:Preliminarydesignandsimulationofafreepistonenginesuitableforsmall-scaleenergyproductionindistributedenergysystemsispresentedinthispaper.Theproperties,particularlythepropertiesofgassealsoftheenginearesimulatedusingasimulationprogramdevelopedforthiscase,andtheresultsareutilizedinpreliminarymaindesignparameterselection.TheenginesimulationprogramwasdevelopedbycombiningandmodifyingthesourcecodesofthesimulationandcalculationprogramsobtainedfromHelsinkiUniversityofTechnology,TampereUniversityofTechnology,andLappeenrantaUniversityofTechnology.Becauseofthecontact-freelabyrinthsealusedinthepiston,theefficiencyofthemotorislowerthantheefficiencyofaconventionalmotorwithoillubricatedpistonrings.Ontheotherhand,thelackofbearinglosses,andthelackoflossesassociatedwithacrankshaftsystemandagearbox,aswellasthelackoflubricationoilexpenses,compensatesthiseffect.Asanetresult,thisnewmotorwouldperformslightlybetterthantheconventionalone.Beingcompletelyoil-free,itisveryenvironmentallyfriendly,anditsexhaustgasesarecompletelyfreeofoilresidualswhicharecausingproblemsinnormalgasmotors.

  • 标签: 自由活塞发动机 迷宫密封 流体动力学模型 分布式能源系统 模拟仿真 密封性能
  • 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:ThispaperestablishesthevelocityfieldandtheadequateshearstresscorrespondingtothemotionofanOldroyd-BfluidbetweentwoinfinitecoaxialcircularcylindersbymeansoffiniteHankeltransforms.Theflowofthefluidisproducedbytheinnercylinderwhichappliesatime-dependentlongitudinalshearstresstothefluid.Theexactanalyticalsolutions,presentedinseriesformintermsofBesselfunctions,satisfyallimposedinitialandboundaryconditions.ThegeneralsolutionscanbeeasilyspecializedtogivesimilarsolutionsforMaxwell,secondgradeandNewtonianfluidsperformingthesamemotion.Finally,somecharacteristicsofthemotionaswellastheinfluenceofthematerialparametersonthebehaviorofthefluidmotionaregraphicallyillustrated.

  • 标签: COUETTE流动 流体运动 HANKEL变换 轴向 纵向剪应力 贝塞尔函数
  • 简介:Thepropagationofmultipolemodalwavesalongthewell-axisinafluid-filledboreholesurroundedbyelasticandnonelastic,infiniteandfiniteformationisanalysedbyusingthewaveequations.Thephasevelocitydispersionandtheexcitationcurvesarenumericallycalculated.Thewaveformsexcitedbyattenuatingburstsarealsocalculated.Themeasurementswithlong-spaceddipoletransducersmadeofPZTthindisksvibratinginbendingmodearecarriedoutinaconcretemodelwellandtheexperimentalresultsarecomparedwiththetheoreticalresults.

  • 标签: DIPOLE EXCITED FLEXURAL BOREHOLE FILLED analysed