学科分类
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431 个结果
  • 简介:ByusingtheReynoldsStressClosureModel(RSM),turbulentCounter-Gradient-Transport(CGT)phenomenonwasnumericallyinvestigatedinasymmetricflowwithajet,andthecomputationalresultswerecomparedwithexperimentaldata.ThecomputationalresultsshowthatthenegativeturbulentenergyproductiononlyappearsatsomecertainstationsinCGTregion,thisfactindicatesthattheCGTphenomenonexistsmorewidelythanthenegativeturbulentenergyproduction;whiletheCGTregionexistsallalong,itgraduallyshrinksinthefavorablepressuregradientzoneuntilthepositionofthewingcentralpartisreached,whereitvanishes,butitappearsintheadversepressuregradientregion;inaddition,thelocationintheflowwhereuv=0switchedsides,relativetowhere()U/()y=0,fromfavorablepressuregradienttoadversepressuregradient.ThepressuregradienttakesanimportanteffectontheregionofnegativeturbulentenergyproductionandCGT.

  • 标签: 流体力学 反梯度传输 雷诺应力闭合模型 压力梯度 湍流
  • 简介:Duringthedevelopmentoflowpermeabilityreservoirs.theinteractionbetweenfluidflowandrock-massdeformationisobvious.Onthebasisoffluidmechanicsinporousmediaandelasto-plastictheory.theauthorpresentsanequivalentcontinuummodeltosimulatefluidflowinfracturedlow-permeabilityoilreservoircoupledwithgeo-stress.Themodelnotonlyreflectstheporositychangeofmatrix,butalsothepermeabilitychangeduetotheopeningandclosingoffracture.Byanalyzingofsimulationresults,thechangesinporosityandpermeabilityandtheireffectonoildevelopmentarestudied.

  • 标签: 液固耦流 断裂低渗透性油库 多孔介质 数值模拟 相互作用 流体机械学
  • 简介:AraisedpanelmethodbasedonNURBS(Non-UniformRationalB-Splines)forfree-surfaceflowswithforwardspeedispresented.Inthisgeneralizedpanelmethod,NURBSareemployedtorepresentthebodygeometry,disturbedfreesurface,andtoexpresstheunknownsourcestrengthdistribution,onthebodysurfaceandabovethefreesurface.Comparedwithcommonhigher-orderpanelmethods,ithasnoneedofadoptinglocalcoordinates.NURBSmakethegeometryrepresentationofthebodyshapeandthewavepatternmoreprecise.Raisedpanelsabovethefreesurfaceproducelessnumericaldispersionerror,needlessCPUconsumptionandarehelpfulandcombinedwithcollocation-pointshiftingup-stream,cansatisfytheradiationconditionnumerically.ByusingcontinuousanddiscreteFourieranalysis,numericalerrorsofthismethodarediscussedandageneralexpressionfortheerrorsofnumericaldampinganddispersion,includingtheeffectsoftheverticaldistanceofsingularitiestothefreesurface,theorderofsingularitydistributionrepresentedbyB-splinesinpanels,andcollocation-pointshiftingisderived.

  • 标签: 凸镶板法 非均匀有理B样条 NURBS 自由表面位势流 前进速度 误差分析