简介:Anewmeshfreemethodproposedbytheauthorswaspresented,inwhichthederivativesateachnodewereconstructedusingwholederivativeformulasthroughthenodesselectedaroundthenodeusinglocalCartesianframeinanautonomousmanner,sothatwithoutanyelementitcouldbeconsideredasacompletelymeshfreemethod.Themethodwastestedwithanumericalexample,andreliablesolutionwasobtainedwithhighaccuracyandefficiency.
简介:Withthedevelopmentofadvancedimagingtechnology,digitalimagesarewidelyused.Thispaperproposesanautomaticquadrilateralmeshgenerationalgorithmformulti-colourimagedstructures.Ittakesanoriginalarbitrarydigitalimageasaninputforautomaticquadrilateralmeshgeneration,thisincludesremovingthenoise,extractingandsmoothingtheboundarygeometriesbetweendifferentcolours,andautomaticall-quadmeshgenerationwiththeaboveboundariesasconstraints.Anapplicationexampleis...
简介:Inthispaper,anewmethodoftopologicalcleanupforquadrilateralmeshispresented.Themethodfirstselectsapatchofmesharoundanirregularnode.Itthenseeksthebestconnectionoftheselectedpatchaccordingtoitsirregularvalenceusinganewtopologicaloperation:smallpolygonreconnection(SPR).Byreplacingtheoriginalpatchwithanoptimalonethathaslessirregularvalence,meshqualitycanbeimproved.Threeapplicationsbasedontheproposedapproachareenumerated:(1)improvingthequalityofaquadrilateralmesh,(2)convertingatriangularmeshtoaquadrilateralone,and(3)adaptingatrianglegeneratortoaquadrilateralone.Thepresentedmethodishighlyeffectiveinallthreeapplications.
简介:Thereliabilityandaccuracyofnumericalresultsofmicroparticlefluidizationinaconicalbed,affectedsimultaneouslybymeshrefinement,thegridconfigurationandthewallboundarycondition(BC),areanalyzed.Specifically,pressuregradientsandvelocityprofilesoftitaniapowderarestudiedforaconicalbed.TheGidaspowdragcorrelationanddifferentwallBCsareconsideredusingaEulerian-Euleriantwo-fluidmodel.Predictionsofthepressurefluctuation,powerspectraofthecorrespondingpressurefluctuations,bedpressuredrop,minimumfluidizationvelocity,axialsolidvelocity,bedexpansionratio,andparticlesizedistributionarecomparedwithexperimentaldata.Meshsensitivityanalysisusinghexahedralandtetrahedralcellswithauniformmeshandnear-wallmeshrefinemenrisconductedtoinvestigatetheeffectsofmeshconfigurationsinestimatingparticleflowpatterns.Simulationsshowthatsignificantsavingsintermsofcomputationaltimearerealizedbychoosingauniformmeshwhilethehexahedralstructure,thenear-wallmeshrefinement,andthefree-slipBCgivetheclosestfittotheexperimentaldata.