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134 个结果
  • 简介:Inthispaper,perturbationmethodandFourier-cosine-expansionmethodareusedtosolvea3-DnonlinearproblemofasupercavitatingflowinaninclinedfieldofgravityatlargeFroudenumbers.Byexpandingthevelocitypotentialintoapowerseriesofasmallparameter,theoriginal3-Dnonlinearproblemisreducedtoanumberof2-Dones.Thesolutionsofthefirstthreeordersarederivedindetailandexpressedintermsofthecompleteellipticintegralsofthefirstandsecondkinds.Thentheboundaryintegralequationmethodisappliedtogetthenumericalsolutionsforeachorder.Computationalresultsareprovidedforsupercavitatingflowspastconesundervariousflowconditions.

  • 标签: supercavitating flow NONLINEAR free surface PERTURBATION
  • 简介:Inthepresenceofbottomwater,adropinthereservoirpressureduetofluidproductioncausestheaquiferwatertoexpandandtoflowintothereservoir.Therefore,hydrocarbonproductionfromawellislimitedbythecriticalflowrate.Themainpurposeofthisstudyistoinvestigatethebreakthroughtimeandthecriticalratebyusinganovel3-Dhorizontalwellmodel.Basedonthehypothesisthatthehorizontalwellislocatedinanypositionofacircularreservoirwithno-flowboundaryonthetopofthereservoirandconstantpressureboundaryatthebottom,thehorizontalwellhasbeenregardedasaninfiniteconductivitylinesinkandthena3-Dsteady-stateflowmodelofthehorizontalwellissetup.ApointsinkpressuresolutioncanbeobtainedwiththeFouriertransform.Theresultofthepressuredistributionoftheuniformfluxhorizontalwellcanbepresentedbymeansoftheprincipleofsuperposition.Accordingtothestablewatercrestingtheory,thisstudyconfirmsthestableheightofwatercrestingandthecriticalrate.Meanwhile,itcanre-confirmthebreakthroughtimeataspecificrate.Theoutputofacomparisonbetweenthis3-Dmodelandthereservoirnumericalsimulator(Eclipse)showsthemethodpresentedherecanbeappliedtoinvestigatethebehaviorofawatercrestingandtopredictthebreakthroughtimeatthebottomwaterdriverreservoir.

  • 标签: 动态分析软件 底水推进技术 临界流量分析 三维模型 水动力学
  • 简介:Inthisarticle,theanaglyphvideomakerisemployedforgeneratingrealistic3-DflowsandthesoftwareFlowAnimatorisdevelopedusingthattechnology.BasedonMicrosoftWindowsPresentationFoundation(WPF),thereal3-Dsceneissetupandmarkerparticlesaredistributedinitrandomlyinordertocreateamorenaturalflowscenario.ThetrajectoryoftheparticlemotioniscalculatedwithLagrangiandescriptionin3-Dspace.Duringthesimulation,theviewportcanbechangedinordertofocusondifferentpartsofthemodelbypanning,zooming,rotatingandinclinationvariationetc.Markerparticlesmayappearindifferentshapes:spheres,tracking-balls,cylindersandribbonsinordertofitdifferentflows.Itisthefirsttimethatthevideoanaglyphtechnologyisemployedinthe3-Dhydrodynamicsimulation,whichremovestheobstaclesfor3-Dscenestoberenderedonaflat-paneldisplay.

  • 标签: 三维流动模拟 立体 视频 MICROSOFT WINDOWS 应用
  • 简介:Ageneralizedbendflowmodel,treatinga90°singlebendand60°continuousbends,wasdesignedtoquantitativelydescribe3-Dturbulencemechanismofcirculatingnot-fully-developedflowinopenchannelswithbends.The3-Dfluctuatingvelocitiesofturbulentflowweremeasuredandanalyzedwitha3-Dacoustic-Dopplervelocimeter.Formulafor3-Dturbulentintensitywasderivedusingthedimensionanalysisapproach.Expressionsofverticalturbulent-intensitydistributionswereobtainedwiththemultivariant-regressiontheory,whichagreewithexperimentdata.Distributionsofturbulentintensityandturbulentstresswerecharacterized,andtheirrelationshipswereconcluded.Inthebend-turbulent-flowcoreregion,longitudinalandlateralturbulent-intensitydistributionsarecoincidentwithlineardistribution,butinnear-wallregionarecoincidentwiththeGammadistribution.VerticalturbulentintensitydistributionsarecoincidentwiththeRayleighdistribution.Herein,itisconcludedthatthebendturbulenceisanisotropic.

  • 标签: 实验性学习 湍动弯曲流动 水道模型 三维湍流强度
  • 简介:Twenty-fiveyearsagoAmerica'ssmallhydroelectricpowergenerationswerereactivatedbyprivate,municipal,andlocalgovernmentstoutilizetherenewableenergyfromthesmallhydrostiesavailable10,000existingdams,smallriversand/orstreams,andenergyrecoveryfacilitiesatmanywatertransmissionanddeliverysystems.

  • 标签: 小型水力发电 中国 电气化建设 美国 数字技术
  • 简介:Whenabodynavigateswithcavityinshallowwater,bothflexiblefreesurfaceandrigidbottomwallwillproducegreatinfluencesonthecavityshapeandhydrodynamicperformances,andfurtheraffectthemotionattitudeandstabilityofthebody.Inthepresentwork,characteristicsofthenaturalcavitatingflowarounda2-Dsymmetricalwedgeinshallowwaterwereinvestigatedandtheinfluencesoftwotypeboundariesontheflowpatternwereanalyzed.TheVolumeOfFluid(VOF)multiphaseflowmethodwhichissuitableforfreesurfaceproblemswasutilized,coupledwithanaturalcavitationmodeltodealwiththemass-transferprocessbetweenliquidandvaporphases.Withintherangeofthecavitationnumberforcomputation(0.07-1.81),thecavityconfigurationswouldbedividedintothreetypes,viz.,stabletype,transitiontypeandwake-vortextype.Inthisarticle,theshapesofthefreesurfaceandthecavitysurface,andthehydrodynamicperformanceofthewedgewerediscussedundertheconditionsofrelativelysmallcavitationnumber(<0.256).Thepresentnumericalcavitylengthsgenerallyaccordwithexperimentaldata.Whenthecavitationnumberwasdecreased,thecavitywasfoundtobecomelongerandthicker,andthescopeofthedeformationofthefreesurfacealsograduallyextends.Thefreesurfaceandtheuppercavitysurfacecorrespondfairlytotheirshapes.However,thelowersideofthecavitysurfacewasratherleveledduetotheinfluenceofwallboundary.Theliftanddragcoefficientsofthis2-Dwedgebasicallykeeplinearrelationswiththenaturalcavitationnumbersmallerthan0.157,whereasdirectproportionfordragandinverseproportionforlift.

  • 标签: 水动力性能 自然科学 楔形 浅水 自由表面 流量
  • 简介:A3-Dtimedomainmethodisdevelopedtoinvestigatethegapinfluenceonthewaveforcesfor3-Dmultiplefloatingstructures.Specialhydrodynamicresonanceduetosmallgapsbetweenmultiplefloatingstructuresonwaveforcesisexamined.Strongandcomplicatehydrodynamicinteractionsbetweenthefloatingbodiesareobservedandthenumericalcomputationshaveprovedtheexistenceofthesharppeakforceresponseoneachfloatingbodyatsomespecialresonantwavenumbers.Bycomparisonwiththeresultsfromthefrequencydomaintechnique,theresultsobtainedfromthetimedomainmethodrevealthesimilarresonantphenomenaandhydrodynamicinteraction.TheresonantwavenumbersarealsoprovedaroundkL=nπ(n=1,2,…,∞)withacorrespondingfrequencyshift.Thestronghydrodynamicinteractionfeatureispracticallysignificantforthedesignofmodulestructuresandthelinks(connection)inwholethefloatingbodysystem.

  • 标签: 时间域 共振技术 流体动力学 浮动体
  • 简介:Three-dimensionalseepageindoublefracturedmediawasmodeledinthispaper.Thedeterminationofhydraulicconductivitytensorofrockmassisavitalproblemfortheseawaterintrusionorseawaterencroachmentandseepageoffissuredmedium.Accordingtothegeologicalandhydrogeologicalconditionsforthe2nd-stageconstructionoftheThreeGorgesProject(TGP),thephysicalandmathematicalmodelsforthegroundwatermovementthroughthe3Ddoublefracturedmediaofrockmassduringconstructionwereestablishedinthispaper.Basedondiscontinuity-controlinversetheory,somerelatedparametersofdoublefracturedmediawereinversedwithfluxbeingtheknownquantityandcalibrationofwatertabletheobjectivefunction.Synchronously,theseepagefieldoftheconstructionregionwassystematicallyanalyzedandsimulated,theresultsofwhichexhibitthatthedoublefracturedmediamodeloffracturewatercancomprehensivelyandcorrectlydescribethegeologicalandhydrogeologicalconditionsintheconstructionregion.

  • 标签: 三峡大坝 三维渗硫 双重断裂介质模型 移动系数
  • 简介:Thispaperisconcernedwiththewavesgeneratedbya3-Dbodyadvancingbeneaththefreesurfacewithconstantspeedinatwo-layerfluidoffinitedepth.ByapplyingGreen'stheorem,alayeredintegralequationsystembasedontheRankinesourcefortheperturbedvelocitypotentialgeneratedbythemovingbodywasderivedwiththepotentialflowtheory.Afour-nodeisoparametricelementmethodwasusedtotreatwiththesolutionofthelayeredintegralequationsystem.Thesurfaceandinterfacewavesgeneratedbyamovingballwerecalculatednumerically.Theresultswerecomparedwiththeanalyticalresultsforamovingsourcewithconstantvelocity.

  • 标签: 内波 二层流 兰金源 有限深度 分层积分方程系统
  • 简介:索风营发电厂自2005年8月首台机组投产以来,在贵州乌江水电开发有限责任公司(华电贵州公司)的正确领导下,在全厂干部职工的共同努力下,从首台机组投产发电至今,已累计正确开停机9216次,

  • 标签: 发电厂 索风营 安全生产 投产发电 水电开发 机组
  • 简介:7月20日晚,由路桥分局承建的国道310西安过境公路项目渭河特大桥2号梁场顺利完成最后一片25米预制箱梁的浇筑,至此完成了西侧100片箱梁预制的全部任务,渭河特大桥东西两侧箱梁预制全部完成。

  • 标签: 预制箱梁 特大桥 渭河 梁场 国道 箱梁预制
  • 简介:1电站概况安民级水电站厂址位于大东坝镇青石坝村,距松阳县城约35km,电站装机容量为2×2000kW,设计年发电量1578万kW·h工程由拦水堰坝、发电输水系统(总长3.37km)、跨流域引水系统(总长2.74km)、发电厂和升压站组成。工程于2003年2月动工建设。2004年9月建成发电。

  • 标签: 输水系统 二级电站 二级水电站 东坝镇 年发电量 跨流域引水