简介：Atheoreticalapproachisderivedtostudyinteractionoflinearwaterwaveswithanairbubblecurtainusedasapneumaticbreakwater.Modellingofwavetransmissionthroughanaerialbarrierisacomplextaskduetoaneedtocoverprocessesassociatedwithwave-currentinteraction,effectsoftwo-phaseflows,wavedamping,etc..Aninitialboundary-valueproblemissolvedbyapplyinganefficienteigenfunctionexpansionmethodandatime-steppingprocedure.Thederivedsemi-analyticalsolutionisusedtostudytheeffectofbasicparametersofthemodelonwavedissipativepropertiesofthepneumaticbreakwater.Resultsshowthatwavedampingbythebreakwaterismainlyaffectedbyanairflowrate.Theincreasedairdischargeresultsinhighervelocitiesofascendingbubblesandincreasesaerialbarrierwidth.Thisleadstoasubstantialreductionoftransmittedwaveheights,especiallyforwavesofintermediatelengthandshortwaves.Inordertoverifytheapplicabilityofthepresentedtheoreticalapproach,laboratoryexperimentsareconductedinawaveflumefordifferentwaveregimesandpneumaticbreakwatercharacteristics.Theanalysisofawavetransmissioncoefficientcalculatednumericallyandmeasuredinthelaboratoryconfirmsthatthederivedmodelcanbeusedforacertainrangeofwaveconditions.

简介：BasedonthePreissmannimplicitschemefortheone-dimensionalSaint-Venantequation,themathematicalmodelforone-dimensionalrivernetworksandcanalnetworkswasdevelopedandthekeyissuesonthemodelwereexpatiatedparticularlyinthisarticle.Thismodelappliesthemethodofthree-stepssolutionforchannel-junction-channeltosimulatetherivernetworks,andtheGausseliminationmethodwasusedtocalculatethesparsematrix.Thismodelwasappliedtosimulatethetree-typeirrigationcanalnetworks,complexloopedchannelnetworksandtheLowerColumbiaSloughnetworks.TheresultsofwaterlevelanddischargeagreewiththedatafromtheAdlulandfielddata.Themodelisprovedtoberobustforsimulatingunsteadyflowsinrivernetworkswithvariousdegreesofcomplexstructure.Thecalculatedresultsshowthatthismodelisusefulforengineeringapplicationsincomplicatedrivernetworks.Futureresearchwasrecommendedtofocusonsettingupecologicalnumericalmodelofwaterqualityinrivernetworksandcanalnetworks.