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简介：在精力平衡实验期间，patch-to-patch灌溉在一块纵贯的面向的棉花地里在土壤潮湿产生了坡度。从相对干燥的在上游的补丁由于强壮的水平移流开发相对弄湿下游的补丁的内部边界层(IBL)与占优势的在北方的风联系了。这产生了多重尺寸的大旋涡，它在IBL在骚乱的结构上有重要影响。在IBL以内在二高度测量的风速度，温度，湿度，和精力流动的力量系列和cospectra被介绍并且过去常在表面层骚乱上调查IBL的影响。系列和cospectra被外部骚乱极大地在低频率提高。这些骚乱的山峰频率没随着高度变化。系列和cospectra典型地收敛了并且与在高频率的堪萨斯光谱平行(在惯性的子域)。当表面层是稳定的时，在水平风速度的系列的清楚的差距在中间的频率存在。结果显示在在上游的对流边界层发源的大旋涡在表面层骚乱的系列和cospectra上有可观的影响。这些大旋涡的影响更大(1)当IBL比IBL什么时候没存在在近的表面层是开发得好的时，(2)在比在底层高级，并且(3)当大气的表面层(ASL)比ASL什么时候是稳定的不稳定时。这些大旋涡的长度规模与在实验地点的表面异质的主导的规模一致。

简介：TheturbulenceflowFreeSurfacehasimportantapplicationsinhydraulicspillwaysstructure,suchasthehydraulicjump,energydissipationflowetc.Thisisbeingconsideredasverycomplicatedflow,andhasnotyetbeensolvedquitewellbynumericalmethod.Inthispaper,aLarge-scalecomputationalsoftwarepackagearedevelopedfornumericallaboratoryofhydraulicspillwaystructure.Somemethods,suchasturbulencemodel,freesurfaceandirregularboundarytreatingtechniques,scientificcomputervisualizationareputforwardandperformed.

简介：InnestednonhydrostaticmesoscalemodelMM5,thecharacteristicquantitiesofatmosphericturbulence,i.e.,thestandarddeviationsoftheturbulentfluctuatedspeedsforthreedirectionsinPBLarecomputedbyMellor-Yamada’slevel2.5closurescheme.Themagnitudesandtheverticalprofilesofthesequantitiescomputedfromthemodelarecloselyconnectedwithtemperatureandwindspeedprofilesaswellasthetypeofthegroundwithasignificantdiurnalvariation,andareinagreementwithknownmagnitudesandregularitiesindifferentstratificationconditions.Hencethemethodinthispaperisreasonableandconvincible.Theirhorizontaldistributiondependsonthehorizontaldistributionofthestratification.Themethodofpredictedcharacteristicquantitiesofturbulencefrommesoscalemodelinthispapercanbeusedintheproblemofatmosphericdiffusionandatmosphericenvironment.

简介：Surfacewavescompriseanimportantaspectoftheinteractionbetweentheatmosphereandtheocean,soadynamicallyconsistentframeworkformodellingatmosphere-oceaninteractionmusttakeaccountofsurfacewaves,eitherimplicitlyorexplicitly.Inordertocalculatetheeffectofwindforcingonwavesandcurrents,andviceversa,itisnecessarytoemployaconsistentformula-tionoftheenergyandmomentumbalancewithintheairflow,wavefield,andwatercolumn.Itisveryadvantageoustoapplysur-face-followingcoordinatesystems,wherebythesteepgradientsinmeanflowpropertiesneartheair-waterinterfaceinthecross-interfacedirectionmayberesolvedoverdistanceswhicharemuchsmallerthantheheightofthewavesthemselves.Wemayaccountforthewavesexplicitlybyemployinganumericalspectralwavemodel,andapplyingasuitabletheoryofwave–meanflowinteraction.Ifthemeanflowissmallcomparedwiththewavephasespeed,perturbationexpansionsofthehydrodynamicequationsinaLagrangianorgeneralizedLagrangianmeanframeworkareuseful:forstrongerflows,suchasforwindblowingoverwaves,thepresenceofcriticallevelswherethemeanflowvelocityisequaltothewavephasespeednecessitatestheapplicationofmoregeneraltypesofsurface-followingcoordinatesystem.Theinteractionoftheflowofairandwaterandassociateddifferencesintemperatureandtheconcentrationofvarioussubstances(suchasgasspecies)givesrisetoacomplexboundary-layerstructureatawiderangeofverticalscales,fromthesub-millimetrescalesofgaseousdiffusion,toseveraltensofmetresfortheturbulentEkmanlayer.Thebal-anceofmomentum,heat,andmassisalsoaffectedsignificantlybybreakingwaves,whichacttoincreasetheeffectiveareaofthesurfaceformasstransfer,andincreaseturbulentdiffusivefluxesviatheconversionofwaveenergytoturbulentkineticenergy.

简介：Westudythetransitiontoturbulenceofchannelflowoffinite-sizeparticlesuspensionsatlowvolumefraction,i.e.,Φ≈0.001.ThecriticalReynoldsnumberabovewhichturbulenceissustainedreducestoRe≈1675,inthepresenceoffewparticles,independentlyoftheinitialcondition,avaluelowerthanthatofthecorrespondingsingle-phaseflow,i.e.,Re≈1775.Inthedilutesuspension,theinitialarrangementoftheparticlesisimportanttotriggerthetransitionatafixedReynoldsnumberandparticlevolumefraction.Asinsinglephaseflows,streamwiseelongateddisturbancesareinitiallyinducedintheflow.Ifparticlescaninduceobliquedisturbanceswithhighenoughenergywithinacertaintime,thestreaksbreakdown,flowexperiencesthetransitiontoturbulenceandtheparticletrajectoriesbecomechaotic.Otherwise,thestreaksdecayintimeandtheparticlesimmigratetowardsthechannelcoreinalaminarflow.

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简介：Fourturbulencemodels,namely,thebasicandnonlinearstress-transportmodelsandthebasicandanisotropick-εmodels,havebeentestedinthecaseofinteractionbetweenalongitudinalvortexpairandaflat-plateboundarylayer.TheresultsoftheirpredictionswerecomparedwithMehtaandBradshaw’smeasure-ments.Inthispaper,partoftheresultsinvolvingthoseofthenonlinearstress-transportmodelandanisotropick-εmodelarepresentedanddiscussed.

简介：Theeffectsofturbulenceontheaerodynamicproperties,especiallysurface-pressurespectraandvortex-inducedvibrations,oftwo-dimensionalrectangularprismswithslendernessratiosof2and4areinvestigatedexperimentally.Particularattentionisgiventoturbulenceintegralscaleef-fectsfromtheview-pointofenergydistributioninfrequencydomain.

简介：Asecond-ordermomenttwo-phaseturbulencemodelforsimulatingdensegas-particleflows(USM-Θmodel),combiningtheunifiedsecond-ordermomenttwophaseturbulencemodelfordilutegas-particleflowswiththekinetictheoryofparticlecollision,isproposed.Theinteractionbetweengasandparticleturbulenceissimulatedusingthetransportequationoftwo-phasevelocitycorrelationwithatwo-time-scaledissipationclosure.Theproposedmodelisappliedtosimulatedensegas-particleflowsinahorizontalchannelandadowner.Simulationresultsandtheircomparisonwithexperimentalresultsshowthatthemodelaccountingforbothanisotropicparticleturbulenceandparticle-particlecollisionisobviouslybetterthanmodelsaccountingforonlyparticleturbulenceoronlyparticle-particlecollision.TheUSM-Θmodelisalsobetterthanthek-ε-kp-Θmodelandthek-ε-kp-εp-ΘmodelinthatthefirstmodelcansimulatetheredistributionofanisotropicparticleReynoldsstresscomponentsduetointer-particlecollision,whereasthesecondandthirdmodelscannot.

简介：这份报纸描述大小和快借助于一个单个传感器在一台低压力汽轮机(并行口)为骚乱紧张的决心采用的processing以后过程反应空气动力学的压力探查。钻塔与MTU飞行器的引擎在合作被设计，可观的努力被放进所有相关模型参数的调整。片计数比率，机翼方面比率，减少的massflow，减少的速度，入口骚乱紧张和雷纳兹数字被选择复制完整的规模LP汽轮机。大小被执行采用一种锁阶段的获得技术以便提供时间汽轮机转子下游的解决的流动地。全部的压力随机变化被有选择地过滤获得，在频率领域，确定的摇摆由于转子片和协调结构。骚乱紧张从在全部的压力和速度变化之间的反的Fourier变换和关联被导出。骚乱紧张的决心为操作汽轮机的条件的发动机代表允许在定子和转子之间的相互作用过程的讨论。

简介：WemodeltheeffectsofweakfluctuationsontheprobabilitydensitiesandnormalizedpowersofvortexmodelsfortheBessel–Gaussphotonbeamwithfractionaltopologicalchargeintheparaxialnon-Kolmogorovturbulencechannel.Wefindthatprobabilitydensityofsignalvortexmodelsisafunctionofdeviationfromthecenterofthephotonbeam,andthefartherawayfromthebeamcenteritis,thesmallertheprobabilitydensityis.Forfractionaltopologicalcharge,theaverageprobabilitydensitiesofsignal/crosstalkvortexmodesoscillatealongthebeamradiusexceptthehalf-integerorder.Asthebeamwaistofthephotonsourcegrows,theaverageprobabilitydensityofsignalandcrosstalkvortexmodesgrowtogether.Moreover,thepeakoftheaverageprobabilitydensityofcrosstalkvortexmodesshiftsoutwardfromthebeamcenterasthebeamwaistgetslarger.Theresultsalsoshowthatthesmallerindexofnon-Kolmogorovturbulenceandthesmallergeneralizedrefractive-indexstructureparametermayleadtothehigheraverageprobabilitydensitiesofsignalvortexmodesandloweraverageprobabilitydensitiesofcrosstalkvortexmodes.Lower-coherenceradiusorbeamwaistcangiverisetolessreductionofthenormalizedpowersofthesignalvortexmodes,whichisoppositetothenormalizedpowersofcrosstalkvortexmodes.

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简介：Takingaccountofturbulenceintensity,non-uniformityofvelocitydistributionattheinitialandsequentsec-tionofhydraulicjumpandfrictionaldragonthefloorwithinjumprange,thispaperderivesnewformulasforcal-culatingtheratioofconjugatedepthsandtheefficiencyofenergydissipationinthetwo-dimensionalfreehydraulicjump.Ithasbeenverifiedbytestdatathatthenewformulasarenotonlyexactintheorybutalsostillbetterinconformitywithpractice.

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简介：三线性二方程的骚乱为k建模吗？蔚，k？蠅和k？1并且非线性的k？1个模型被用于空气动力学、热的汽轮机流动预言。在片上的wake和热转移系数的压力侧面与试验性的数据相比。好同意与线性k被获得吗？1当模特儿。没有重要修正与非线性的模型一起被观察。在片的条款弄醒的运输方程的平衡也被介绍。线性、非线性的k？1个模型被评估预言描述汽轮机流动的三维的旋涡。模拟证明经过旋涡是损失的主要起源。关键词骚乱模型-数字模拟-turbomachineryCLC数字O357.5

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简介：基于空间差异接收，调音的二进制阶段移动(BPSK)调制了空间光(FSO)在M潣湲牥漠?畯?諠湜K愠?瑩?扯敪瑣上的系统