模具设计外文翻译--注射／压缩流体组合模塑的数值模拟-模具设计

附录二：外文翻译原件及翻译稿Numerical simulation of injection/compression liquid composite moldingPart 1. Mesh gen

附录二：外文翻译原件及翻译稿 Numericalsimulationofinjection/compressionliquidcompositemolding Part1.Meshgeneration aab K.M.Pillai,C.L.TuckerIII,F.R.PhelanJr a DepartmentofMechanicalandIndustrialEngineering,UniversityofIllinois, 1206W.GreenStreet,Urbana,IL61801,USA b PolymerCompositesGroup,PolymersDivision,Building224,RoomB108,NationalInstituteof StandardsandTechnology,Gaithersburg,MD20899,USA Accepted14June1999 ─────────────────────────────────────── Abstract Thispaperpresentsanumericalsimulationofinjection/compressionliquidcompositemolding,wherethefiber preformiscompressedtoadesireddegreeafteraninitialchargeofresinhasbeeninjectedintothemold.Dueto thepossibilityofaninitialgapatthetopofthepreformandout-of-planeheterogeneityinthemulti-layeredfiber preform,afullthree-dimensional(3D)flowsimulationisessential.Weproposeanalgorithmtogenerateasuitable 3Dfiniteelementmesh,startingfromatwo-dimensionalshellmeshrepresentingthegeometryofthemoldcavity. Sincedifferentlayersofthepreformhavedifferentcompressibility,andsincepropertiessuchaspermeabilityarea strongfunctionofthedegreeofcompression,asimultaneouspredictionofpreformcompressionalongwiththe resinflowisnecessaryforaccuratemoldfillingsimulation.Thealgorithmcreatesacoarsermechanicalmeshto simulatecompressionofthepreform,andafinerflowmeshtosimulatethemotionoftheresininthepreformand gap.Linesconnectedtothetopandbottomplatesofthemold,calledspines,areusedasconduitsforthenodes.A methodtogenerateasurfaceparalleltoagivensurface,therebymaintainingthethicknessoftheintermediate space,isusedtoconstructthelayersofthepreforminthemechanicalmesh.Themechanicalmeshisfurther subdividedalongthespinestocreatetheflowmesh.Examplesofthethree-dimensionalmeshesgeneratedbythe algorithmarepresented.1999ElsevierScienceLtd.Allrightsreserved. Keywords: Liquidcompositemolding(LCM);E.Resintransfermolding(RTM) ─────────────────────────────────────── 1.Introduction Liquidcompositemolding(LCM)isemergingasanimportanttechnologytomakenet-shape partsofpolymer-matrixcomposites.InanyLCMprocess,apreformofreinforcingfibersisplaced inaclosedmold,thenaliquidpolymerresinisinjectedintothemoldtoinfiltratethepreform. Whenthemoldisfull,thepolymeriscuredbyacrosslinkingreactiontobecomearigidsolid. Thenthemoldisopenedtoremovethepart.LCMprocessesofferawaytoproduce high-performancecompositepartsusingarapidprocesswithlowlaborrequirement. ThispaperdealswithaparticulartypeofLCMprocesscalledinjection/compressionliquid compositemolding(I/C-LCM).InI/C-LCM,unlikeothertypesofLCMprocesses,themoldis onlypartiallyclosedwhenresininjectionbegins.Thisincreasesthecross-sectionalareaavailable fortheresinflow,anddecreasesflowresistancebyprovidinghighporosityinthereinforcement.