Page 67 - 2023年第54卷第6期
P. 67

Dailyrunoffsimulationbasedonseasonallong - term memoryDARmodel

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                                     WANGHuimin ,SONGSongbai ,ZHANGGengxi
                       (1.CollegeofWaterResourcesandArchitecturalEngineering,NorthwestA&FUniversity,Yangling 712100,China;
                         2.KeyLaboratoryofAgriculturalSoilandWaterEngineeringinAridandSemiaridAreas,MinistryofEducation,
                                           NorthwestA&FUniversity,Yangling 712100,China;
                            3.CollegeofHydraulicScienceandEngineering,YangzhouUniversity,Yangzhou 225009,China)

                  Abstract:Traditionaltimeseriesmodelshavestrictparameterrangesandcannotsimultaneouslyconsiderthelong -
                  termmemoryandtime - varyingvolatilityofrunoffseries,whichlimitstheapplicabilityofdailyrunoffseriesandaf
                  fectsthesimulationaccuracy.Thisstudyproposesanewdoubleautoregressivemodel (WOA - SFIDAR)thatcan
                  simultaneouslydescribenon - stationarity,seasonality,long - memoryandtime - varyingvolatility,andcomparesit
                  withthetraditionallong - memoryvolatilitymodel(SFIAR - GARCH).FourhydrologicalstationsintheWeiheRiver
                  basinareselectedtoestablishmodelsforsimulationverification.Theresultsshowthatthesimulationabilityofthe
                  WOA - SFIDARmodelisbetterthanthatofthetraditionalSFIAR - GARCHmodel,andthesimulationresultswell
                  preservethestatisticalcharacteristicsofthedailyrunoffprocess ;thesimulationerrorofaveragerunoffinJulyand
                  Augustarerelativelylarge,andtheerrorrangeoftheWOA - SFIDARmodel(5.72 - 32.56)islowerthanthatof
                  theSFIAR - GARCHmodel(7.42 - 48.02);thedeviationrangesbetweenthemonthlyvariationcoefficient(C v )
                  andskewnesscoefficient(C s )simulatedbyWOA - SFIDARandthestatisticalvaluesofthemonthlymeasuredseries
                  are0 - 0.51and0.02 - 1.31 ,whicharelowerthanthoseoftheSFIAR - GARCH model(0.02 - 0.56and0.06 -
                  1.52);thesimulateddailyrunoffwelldescribesthevariationtrendoftheautocorrelationcoefficient(ACF)ofthe
                  measuredseries ,andthegapinACFshrinkswithincreasinglags.Themodelproposedinthisstudyexpandsthe
                  hydrologicalstochasticsimulationmethod ,andprovidesanewapproachforrunoffsimulationandforecasting.
                  Keywords:long - termmemory;time - varyingvolatility;runoffsimulation;doubleautoregressivemodel;Weihe
                  Riverbasin
                                                                                    (责任编辑:于福亮)


              (上接第 685页)
                     Studyonthehydraulicsofverticaltrapezoidalsluicegateunderfreeflowconditions

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                                                 LILin ,ZHAOShuaijie
                         (1.CollegeofHydraulicandCivilEngineeringofXinjiangAgriculturalUniversity,Urumqi 830052,China;
                    2.XinjiangKeyLaboratoryofWaterConservancyEngineeringSafetyandWaterDisasterPrevention,Urumqi 830052,China)

                  Abstract:Verticaltrapezoidalgateisanewtypeofflatgate,whichhasadvantagesoverconventionalrectangular
                  gatesinflowcontrolanddiversionapplicationsinirrigationareasatalllevelsoftrapezoidalchannelsbecauseitdoes
                  notneedtobuildauxiliarybuildingssuchasgatechambersandtorsionsurfacesandoccupiesasmallerarea.The
                  overflowboundaryconditionsoftrapezoidalgatesaredifferentfromthoseofrectangulargates ,inthisstudy,atotal
                  of186testswereconductedforstudyingthehydraulicperformanceofthetrapezoidal - shapedsluicegatesbuiltinthe
                  trapezoidalcanalswithsideslopesof1.5 ,1.75and2,respectively.Theeffectsofparameterssuchasgateopening
                  eandwaterdepthinfrontofthegateH 0 ontheflowpatternanddischargeafterthegatewereanalyzed,andthedis
                  chargecalculationmethodforfreeoutflowoftrapezoidalgateswasstudiedbasedonthetestdata.Theresultsindica
                  tedthattheoutletflowthroughthegateweredividedintothreejets.Thecollisionofthejetsformsahump,which
                  resultsinacontractedcross - sectionwiththesmallestwatersurfacewidth ,thelargestwaterdepthatthecenterline.
                  Whenthedischargeandtherelativeopeningofthegatearedoubledrespectively ,thedistanceofthehumpfromthe
                  gatechangesfrom3.6 eand8.2eto6.0eand3.3e,andtheheightofthehumpchangesfrom1.5eand3.0eto2.4e
                  and1.5e,andthedistancerequiredforthewaterflowinthechanneldownstreamofthehumptobeevenlydistribu
                  tedchangesfrom15.0 eand33.0eto34.0eand17.0e.Theflowexhibitedwavyappearancewithalternatecontraction
                  andexpansioninstreamwiseandwidthdirectionduetotheinterchangebetweenkineticandpotentialenergies ,and
                  thefluctuationdecreasedwiththedissipationoftotalenergy.Theaveragerelativeerroroftheflowcoefficientformu
                  laobtainedwas2.17%,andthedatawithrelativeerrorslessthan6% accountedfor96.3%.Theresultscanprovide
                  referencefortheengineeringdesignandoperationmanagementoftrapezoidalsluicegateinpractice.
                  Keywords:trapezoidalsluicegates;freeflow;discharge;dischargecoefficient
                                                                                    (责任编辑:李福田)

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