资源描述:
《Heat Transfer and Consolidation Modeling of Composite Fiber Tow(PhD)》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、HeatTransferandConsolidationModelingofCompositeFiberTowinFiberPlacementByMunkiLeeDissertationsubmittedtotheFacultyoftheVirginiaPolytechnicInstitute&StateUniversityinFulfillmentoftheRequirementsfortheDegreeOfDoctorofPhilosophyInMechanicalEngineeringApprovedbyDr.RobertH.Sturg
2、es,ChairmanDr.DonaldG.BairdDr.MichaelP.DeisenrothDr.CharlesF.ReinholtzDr.DonaldJ.LeoKeyWords:HeatTransfer,CompositeManufacturing,FiberPlacement,Modeling,Consolidation,TemperatureControlMarch19,2004Blacksburg,VirginiaHeatTransferandConsolidationModelingofCompositeFiberTowinF
3、iberPlacementByMunkiLeeABSTRACTWiththeinitialproductionofadvancedcomposites,theuseofcompositematerialshasbeengrowingrapidlyinmanyindustrialfields.Themajorimpacthasbeenwiththeweight-sensitiveaerospaceapplications,wherehighstrength/stiffness-to-weightratiosareveryimportantfac
4、tors.Conventionally,compositesstructurefabricationwasconductedbyhandlay-upandsubsequentautoclave-basedcuringprocesses.However,thedemandforcost-effectiveandefficientcompositemanufacturingisgrowingandthusperpetuatingthereplacementofexistinghandlay-upprocessing.Automatedfiberp
5、lacementdrawsspecialattentionforitslowcostpotential,flexible,andautomatedprocess.ThisfiberplacementwasinvestigatedthroughtheFunctionBlockDiagramapproach,andasaresult,itwasconcludedthattwosub-processes,heattowpregandcompacttowpreg,areopportunityareasforbetterfiberplacementpr
6、ocess.Thisdissertationdevelopsaheattransfermodelwithnewheatingalternativesfortheheattowpregsub-processandanalyzescompactionforcewithacurrentlyusedpneumaticmechanismforthecompacttowpregsub-process.Alinearcompositetowpregwasmodeledwithuniformmaterialpropertiesinone-dimensiona
7、longthethickness.Thereafter,aheattransfermodelbetweenthetowpregandheatingtoolssuchashotgas,fluid,andrigidcontactheatsources,wasdeveloped.Thesimulationresultsshowthatarigidcontactheatingisanoutstandingheatingalternativefrombothmanufacturingandenergy-efficiencystandpoints.The
8、manufacturingspeedofrigidcontact-heating,withaconstantheatingtemperatureof200°Cisa