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  • 简介:Inthepresentpaperitwillbeshownthat,bytakingthereferenceframemovingwiththevelocityoffluidattheinterlaceoftwosteadyparallelstreams,thelaminarboundarylayerflowinthetwofluidscanbedecoupledintotwoflows.Theseareexactlythesameasthelaminarboundarylayerflowsalongaflatplate.Andthat,byusingtheexistingexactsolutionofthelaminarboundarylayerequationfortheboundarylayerflowalongaflatplateandappropriateboundaryconditions.Anexactsolutionofthelaminarboundarylayerequationforthelaminarboundarylayerbetweentwoparallelstreamswithdifferentdensities,viscocitiesandvelocitiesisgivenelegantly.ForthecasesconsideredbyLock,theresultsobtainedbythepresentmethodarecomparedwithLock’snumericalcalculationsindetail.

  • 标签: BOUNDARY kyer PARALLEL STREAMS Blasius SOLUTION
  • 简介:Theatmosphericgeneralcirculationmodelcoupledtothemixedlayeroceanmodelhasbeenusedtosimulatethechangesoftheglobalsoilmoisture.Comparingthesimulatedresultswithobservations,itisshownthatthemodelisca-pableofdoingsensitiveexperimentsaboutthecarbondioxidechange.The2×CO2/1×CO2comparisonshowsthattherearetheobviouschangesofthesoilmoistureintheglobalforfourseasons.Therearethewetsoilmoistureinthelowerlatitudesofbothhemispheresanddrysoilmoistureinthemid-dlelatitudesofbothhemispheresforfourseasons.Thedrysoilmoistureinsummerandwetinotherseasonsarefoundinthenorthernhigherlatitudes.TheanalysesofthephysicalfeedbacksresponsiblefortheCO2-inducedchangesofsoilmoistureshowthatthebud-getsofthesurfacewaterandheataretheimportantfactors.

  • 标签: soil moisture general CIRCULATION model SEASONAL
  • 简介:Inthispaper,takingitsturbulentexchangecoefficientasafunctionoftheLagrangiantimescaleandstandardvarianceoftheturbulenceinatmosphere,theatmosphericdispersionPDFmodelsareobtainedonthebasisofatmosphericdiffusionK-theory.Inthemodelthestatisticsofwindspeedaredirectlyusedasitsparametersinsteadofclassicdispersionparameters.Thebi-GaussianPDFisderivedinconvectiveboundarylayer(CBL),fromthestatisticsofverticalvelocityinbothofthedowndraftandupdraftregionsthatareinvestigatedtheoreticallyintheotherpartofthispaper.GivingthedrivenparametersoftheCBL(includingtheconvectivevelocityscalew*andthemixingdepthh_i)andthetime-averagedwindspeedatreleaselevel,thePDFmodelisabletosimulatethedistributionofconcentrationreleasedatanylevelsintheCBL.ThePDF’ssimulationsarefairlyconsistentwiththemeasurementsinCONDORSexperimentortheresultsbroughtoutbysomenumericalsimulations.

  • 标签: ATMOSPHERIC DIFFUSION PROBABILITY distribution function (PDF)
  • 简介:ADopplersodarsystemcontrolledbymicrocomputerisdescribedinthispaper.Thesodarwasusedtodetecttheverticaldistributionofwindandtemperaturestratificationintheatmosphericboundarylayer.Thedetectingresultsshowthatatnighttheverticaldistributionofwindisverycomplicated,whichcanappearasastructureoftwoorthreelayers.Innocturnalatmosphericboundarylayersometimesthereexistsverythinlayerinmulti-layerinversionanditcanberetainedforalongtime.

  • 标签: DOPPLER SODAR ATMOSPHERIC boundary layer WIND
  • 简介:ThebiomassesoffishesatthebottomlayeroftheBohaiSeaareextimatedbyanalysingthedataonsamples(447hauls,morethan0.2millioninnumberor20tinweightoffishes)collectedmonthlybyourinstitutefromApril,1982toMay,1983byapairofbottomtrawlsthroughtheBohaiSea.Theexploitationproblemsarealsodiscussedinthispaper.

  • 标签: Bohai EXPLOITATION biomass institute SEASONAL FIFTH
  • 简介:THESTUDYOFTHECHARACTERISTICSOFBOUNDARYLAYEROVERHILLTERRAINHaoWeifeng(郝为锋),LiuKai(刘凯)(MeteorologicalCollegeofAirForce,Nanjing...

  • 标签: PLANETARY boundary layer HILL TERRAIN WIND
  • 简介:NUMERICALSIMULATIONOFDIMETHYLSULFIDEINTHEREMOTEMARINEBOUNDARYLAYERZhengMin(郑敏)andLiXingsheng(李兴生)NUMERICALSIMULATIONOFDIMETHY...

  • 标签: 郑敏
  • 简介:ANALYSISOFMEANWINDCHARACTERISTICSINTHEATMOSPHERICSURFACELAYEROFTHEGRASSLANDAREAINNORTHCHINAXueHeng(薛桁),ZhuRuizhao(朱瑞兆)andWuHo...

  • 标签: 吴虹
  • 简介:StudyontheThermalinternalBoundaryLayerandDispersionofAirPollutantinCoastalAreabyNumericalSimulation¥JiangWeimei(蒋维楣)andYuHong...

  • 标签: ATMOSPHERIC DISPERSION THERMAL INTERNAL BOUNDARY Layer
  • 简介:地震成像质量对描述水库批评。有许多方法,能改进成像质量;一些依靠处理工具推进,而其它依靠改变地获得方法。然而,大多数获得方法集中于由没有认为目标层照明是精力,使用填入射击改进成像。而且,极大地射击的全部的填入增加获得费用。在这份报纸,我们在场为由自动本地填入最大化贡献到目标阴影区域照明射击的一个新方法。因此,我们设计了2D和3D模型并且由向前当模特儿获得了深度迁居节,填入射击,深度移植,等等。模型结果也证明由选择射击的点的最适当的数字,我们能提高阴影区域精力并且以低成本改进目标层成像质量。

  • 标签: 拍摄方法 成像质量 自动填充 目的层 均匀 采集方法
  • 简介:Inthispaper,thesimultaneouseffectsofboundarylayerandtopographyontheinstabilityofEadywaveareinvestigatedbyusinganewparameterizationoftheverticalvelocityatthetopofPBLandtheinfluencesofthestratificationofthePBL,roughnessandtheslopeofterrainareshown.Furthermore,theeffectsoftheboundarylayerfrictionandtopographyongeneralizedEadywavearealsoinvestigated.

  • 标签: simultaneous terrain roughness TOPOGRAPHY STRATIFICATION INSTABILITY
  • 简介:Permittivityofaseafoamlayerisveryimportantininvestigatingoceanbrightnesstemperaturemodel.Atmicrowavefrequency,theRayleighmethodisdevelopedtoestimatetheeffectivepermittivityoftheseafoamlayer.TosimplifythetediouscalculationofseafoameffectivepermittivityatLband(1.4GHz),Pade’approximationisadoptedtofittheseafoameffectivepermittivitycomputedbytheRayleighmethod.Withthisfittingformula,anewbrightnesstemperaturemodelofseafoamlayerdefinedbycertaingeophysicalparameters,suchasairvolumefraction(AVF),seasurfacetemperature(SST),seasurfacesalinity(SSS)andthicknessoffoamlayerd,isgiven.Furthermore,thesensitivitiesofthebrightnesstemperaturemodeltoSST,SSS,dandAVFofaseafoamlayeratLbandarediscussed.Thesensitivitiesarerankedfrommosttoleastintheorder:(1)d;(2)AVF;(3)SSS;(4)SST.ThisresultindicatesthatthemeasurementerrorsofdandAVFhavesignificantimpactsontheretrievalsofSSSandSST.Withtheexperimentalbrightnesstemperaturedata,theSSSandAFVareretrievedbycostfunction.

  • 标签: 温度模型 泡沫层 L波段 亮度 海水 有效介电常数
  • 简介:-Aone-layertime-invarianteddyviscositymodelisspecifiedtodevelopamathematicalmodelfordescribingtheessentialfeaturesoftheturbulentwaveboundarylayeroveraroughbed.Thefunctionalformoftheeddyviscosityisevaluatedbasedoncomputationalresultsfromatwo-equationturbulencemodelinwhichtheeddyviscosityvarieswithtimeandspace.Thepresenteddyviscositymodelsimplifiesmuchofthemathematicalcomplexityinmanyexistingmodels.Predictionsfromthepresentmodelhavebeencomparedwithawiderangeofexperimentaldata.Itisfoundthattheeddyviscositymodeladoptedinthepresentstudyisphysicallyreasonable.

  • 标签: TURBULENT WAVE boundary layer EDDY VISCOSITY
  • 简介:沿着在长江的更低的活动范围的Meiyu前面的重降雨事件在2009年6月23日与一个mesoscale骚乱旋涡被连接,这被发现,它从行星的边界层(PBL)发源并且以后向上发展了并且被使用过滤方法的Shuman-Shapiro发现。在在这个过程的PBL(PMDV)的mesoscale骚乱旋涡在Doppler雷达回响对应于很好短时间的暴风雨。从先进天气研究和预报模型(ARW)的高分辨率的模拟结果的分析证明沿着在PMDV的产生以前的Meiyu前面的南部的温暖的节有几表面骚乱。PMDV与mesoscale交往了对流系统(MCS)并且加强了本地对流降水。在PBL的北方和西南流动在PMDV形成的时候收敛了。同时,到旋涡的南方方面的PBL的顶上的一口西南的喷气增强了上升运动和集中。因此,shear线的强壮的冷空气流动北方什么时候shear线向南遇到了西南流动,被结束PMDV被产生。在PBL,西南风的增强,和北方风的向南方的侵略的集中线为PMDV的发展是批评的。当它在底层便于集中,潜伏的热的版本为PMDV的形成被发现关键。

  • 标签: 行星边界层 中尺度涡 数值模拟 梅雨锋 中尺度对流系统 中尺度扰动
  • 简介:Globalseismicitycatalogsaresufficientforcharacterizingdoubleseismiczones(DSZs)insubductingslabandfacilitatetoestimatelayerseparationwithoutinconsistentuncertaintiesaslocalcatalogs.PreviousstudieshaveshownthecorrelationbetweenDSZslayerseparationandplateagewhilecorrelationforthoseyoungerthan~60Maissuspicious.ThelackingofDSZswithlayerseparationlessthan10kmfurthermakesitdifficulttopreciselyestimatesuchcorrelation.Thus,weincorporateeightDSZsdatadeterminedthroughlocalseismicityintoglobally-determineddatasetandreexaminesuchcorrelation.Thebestfittingresultsshowthatbothalinearmodelandasquarerootofplateagecanmathematicallyfitthelayerseparationwell.However,itisdifficulttodistinguishthesetwomodelswhenplateageisgreaterthan~20Masincetheirdifferenceislessthan2km.However,ifextrapolationispossible,bothmodelsshouldprovidephysicalinformationthatDSZswillnotformifthereisnosubductinglithosphere.Asaresult,theDSZscannotbeproduceduntiltheoceaniclithosphericagebecomesgreaterthan0.9Mainthesquarerootmodelwhilethelinearmodelgivesamisleadingresult.Assuchthesquarerootmodeldemonstratestherelationshipphysicallybetterthanthelinearone,itstillneedsfurthertestinthefuturewithmoreavailabledata,nevertheless,ourstudymightalsoprovideevidenceforthesuggestionthattheplateageisaprimarycontrolfactoroftheDSZsgeometryaswellasthesubductingprocesswhichdisregardsanylocaltectonicstresses.

  • 标签:
  • 简介:Theperfectlymatchedlayer(PML)isaneffectivetechniquefortruncatingunboundeddomainswithminimalspuriousreflections.Afluidparabolicequation(PE)modelapplyingPMLtechniquewaspreviouslyusedtoanalyzethesoundpropagationprobleminarange-dependentwaveguide(LuandZhu,2007).However,LuandZhuonlyconsideredastandardfluidPEtodemonstratethecapabilityofthePMLanddidnottakeimprovedone-waymodelsintoconsideration.Theyapplieda[1/1]Padéapproximanttotheparabolicequation.Thehigher-orderPEsaremoreaccuratethanstandardoneswhenaverylargeanglepropagationisconsidered.Asforrange-dependentproblems,thetechniquestohandletheverticalinterfacebetweenadjacentregionsaremainlyenergyconservingandsingle-scattering.Inthispaper,thePMLtechniqueisgeneralizedtothehigherorderelasticPE,asistothehigherorderfluidPE.Thecorrectionofenergyconservingisusedinrange-dependentwaveguides.Simulationismadeinbothacousticcasesandseismo-acousticcases.Range-independentandrange-dependentwaveguidesarebothadoptedtotesttheaccuracyandefficiencyofthismethod.ThenumericalresultsillustratethataPMLismuchmoreeffectivethananartificialabsorbinglayer(ABL)bothinacousticandseismo-acousticsoundpropagationmodeling.

  • 标签: ELASTIC PARABOLIC EQUATION perfectly matched LAYER
  • 简介:mesoscale在边界层和表面流动的狂暴的交换系数的计算在被改进的数字天气预言模型(MM4),被用来在mesoscale模型的预兆的结果上学习边界层parameterization计划的影响。七个不同实验计划(包括原来的MM4模型)在这份报纸设计了被几大雨格的观察数据测试以便发现改进边界层parameterization在mesoscale的计划气象学的模型。结果证明所有七个不同边界层parameterization计划在降水紧张,雨区域的分发,垂直速度,涡度和分叉地的预报上有一些影响,并且在这的改进计划糊能改进降水预报。关键词边界层parameterization-Mesoscale数字天气预言(MNWP)-狂暴的交换系数-表面流动-大雨这份报纸被中国(资助号码49875005和号码49735180)的国家自然科学基础支持。

  • 标签: Boundary layer PARAMETERIZATION MESOSCALE numerical weather
  • 简介:摘要:本文旨在研究热力交换站温度的控制方法,以提高能源利用效率和供热系统的稳定性。通过分析现有的温度控制策略和技术,探讨了不同控制方法的优缺点,并提出了一种综合考虑供热需求和能源消耗的温度控制方案。通过实验和模拟验证,证明了该控制方案在提高供热效果和节能方面的有效性。本研究对于热力交换站的运行管理和温度控制策略的优化具有一定的理论指导和实践应用价值。

  • 标签: 热力交换站 温度控制 能源利用效率 供热系统 稳定性
  • 简介:Thestructureofatmosphericboundarylayerdeterminestheabilityofatmosphericdispersionandhasanessentialimpactonairborneaerosols.Inthispaper,thedataofaradiosoundingexperimentheldinDongguanNationalMeteorologicalObservationStation,whichisinacoastalcityinPearlRiverDelta,aswellasthedataofatmosphericaerosols,wereutilizedinordertoanalyzethecharacteristicsofatmosphericboundarylayeranditseffectsonsurfaceaerosolconcentrations.Theresultsareshowedatfollows:thelocalcirculations,associatedwithdominantwinds,madecomplexstructuresofatmosphericlayers,asthecoldairandsystematicwindsweakenedintheendofacoldairevent.Weakenedwindshearsandinversionlayers,especiallyastrongnear-surfaceinversionlayer,remarkablydiminishedtheatmosphericdiffusionabilitiesandfacilitatedanespeciallyhighconcentrationofsurfaceaerosols.Theconvergencelineorweakshearlineofseabreezeinthegroundlevelhelpsweakentheatmosphericdiffusionabilitiesandresultsinatmosphericaerosolsaccumulation.

  • 标签: boundary layer characteristics aerosol concentration radio sounding Dongguan