轿车B柱耐撞性与轻量化优化设计研究

B谭耀武杨济匡王四文湖南大学汽车车身先进设计制造国家重点实验室,长沙,410082:为了在提高轿车侧面碰撞中B柱耐撞性能的同时减小B柱的质量以实现车身轻量化,对某车侧面碰撞的安全性能进行了有限元分析针对在侧面碰撞中B柱腰线处侵入量和侵入速度过大B柱结构中加强板数目较多及超重等问题,采用拼焊板结构对B柱外板进行了改进设计在兼顾耐撞性与轻量化的前提下,使用正交试验设计和多目标遗传算法对拼焊焊缝的位置以及各部分的厚度进行优化通过优化设计,改善了B柱在侧面碰撞中的变形模式B柱最大侵入量减小了10%,腰线处侵入量和侵入速度分别减小了18%和12%,质量减小了18%结果表明,在B柱上使用拼焊板结构并进行优化设计能够有效地平衡耐撞性和轻量化的要求:;;B;:U461.91:1004132X(2010)23288706StudyonOptimalDesignofB-pillarforCrashworthinessandLight-weightingTanYaowuYangJikuangWangSiwenStateKeyLaboratoryofAdvancedDesignandManufactureforVehicleBody,HunanUniversity,Changsha,410082Abstract:InordertoenhancecrashworthinessofB-pillarinsideimpactandreduceitsmassatthesametimetoachievelight-weighting,thesafetyperformanceofacarwasanalyzedaccordingtothedesignparametersoftheB-pillarinsideimpactfirstly.ItisidentifiedthattheintrusionandintrusionvelocityatthemiddleoftheB-pillararetoolargeandthemassoftheB-pillarstructureisratherhighduetoextrareinforcements.AnimproveddesignoftheB-pillarwasimplementedusingthetailor-weldedblankstructure.Furthermorethelocationofweldandthicknessofthisstructurewereoptimizedbyusingdesignofexperimentalmethodandmulti-objectivegeneticalgorithm,consideringcrashworthinessandlight-weighting.AdesireddeformationmodeofB-pillarwasfinallyobtained.Itsmaximumintrusionisreducedby10%.TheintrusionandintrusionvelocityatthemiddleofB-pillararereducedby18%and12%respectively.Themassisreducedby18%.TheresultsindicatethatoptimaldesignofB-pillarstructurewithtailor-weldedblankcaneffectivelybalancetherequirementsofcrashworthinessandlight-weighting.Keywords:crashworthiness;light-weighting;B-pillar;optimaldesign:20100127:(863)(2006AA110101);111!(111-2-11);(531105050037);(60870004)0引言,,,[1],,[2]Min[3],,,,Shin[4]Lee[5]Zhu[2]Song[6],[7],[8],[9]B,B2887BBMarklund[1],B,B25%[10]BAltairOptiStructB,BBB![11],(),B,B1多目标优化准备1.1∀#50km/h,101s,2B2,,,,5%121.2LS-DYNA,34,,,34B-B,,B(1)B,,(RDC)B[12],(2)B,5,5B,B288821232010121.3B,,,[12],,B,B,B[11],6B,,,[13],,BB,7,6B7B,[2],B1~4,5,B1~4BBB,88B2多目标优化问题描述2.1,,BUmBLwvw,BMB,,B!,B180mm,Um∃180mm,7~10m/s8m/s[9]Bvw7~8m/s7,t1t2h()3t1t2,08~25mm,hB,136~455mm2.2minF(x)=(f1(x),f2(x),%,fk(x))Ts.t.x&Sx=(x1,x2,%,xn)T(1),f1(x),f2(x),%,fk(x)k;x1,x2,%,xn;S,S&Rn,min(Lw,M)s.t.Um∃180mm7m/s∃vw∃8m/s0.8mm∃t1,t2∃2.5mm136mm∃h∃455mm(2)3多目标优化过程:,,:,;,2889B,;,3.1,[14],,,,L9(34)ht1t2,LS-DYNA9,vwMLwUm,11Lw(mm)vw(m/s)Um(mm)M(kg)11678.84383207.07.16821277.17791146.19.29931137.25814128.911.4341658.92927182.89.22851387.21126171.58.26961157.18257139.710.4071789.90218192.48.36081287.55589134.710.4991307.14635171.19.0453.2,,,:f(x)=0+∋ni=1(ixi)+∋ni=1∋nj(i(ijxixj)+%(3),xinxi;0iij,,,(3),R2R2adj,R2R2adj1,,,,R2adjR2,,R2adj,,B,,:M=3.616222+1.699722t1+1.851944t2(4)Um=382.5351+0.16043h-194.333t1-61.8978t2-0.08358ht2+47.06213t12+18.333t22(5)Lw=267.3179+0.182366h-160.91t1-0.07412ht2+8.7998t1t2+31.53953t21(6)vw=14.56747+0.011814h-10.1768t1-0.00486ht2+1.023188t1t2+2.064668t21(7),MUmLwvwR20994099809970984R2adj0992099209930956,,,3.3NSGA-)(non-dominatedsortinggeneticalgorithm))Deb[15]NSGA,ParetoPareto,,NSGA,NSGA-)iSIGHT,30,1004优化结果,,ParetoPareto,,,,Pareto,,iSIGHTPareto30,2289021232010122ParetoLw(mm)Um(mm)M(kg)vw(m/s)1125.11154.749.2507.0022122.43149.439.5907.0053117.25132.7910.4207.0014137.06179.847.5007.0135118.50134.9910.3107.0016119.89136.2910.1507.0037109.81131.9111.0607.0018122.36139.389.9307.0369128.94160.688.7507.01210128.17158.398.9307.04411125.79157.029.1607.00312134.11168.358.0107.00113130.51163.948.6107.04914114.98130.8810.6607.01015111.16132.8711.0507.08716120.96137.7410.0307.00417112.23130.3210.8707.01118133.25174.328.3507.11719131.77172.818.4207.04920119.41135.9610.2207.00421116.27131.7410.5707.02322124.57153.629.3107.00023126.99157.079.0207.01324127.91156.958.9807.05325111.37131.7310.9607.03526113.35130.1710.8007.00727135.32172.937.8007.00328113.20130.1710.8107.00429109.78131.9811.0607.00130134.68168.708.0107.035,:,B,B180mm,2910132324t1t2h33mmt1t2h91.1031.818320.75101.1481.874336.18131.0531.789321.49231.1651.909337.12241.1791.874336.1823,913,102324,910t1t2h,45%,4910(%)(%)(%)Lw(mm)163.000128.900133.0003.118.4128.700132.0002.519.0Um(mm)183.100160.680164.6002.410.1158.390163.7003.210.6M(kg)10.7638.7508.8140.718.18.9308.9760.416.6vw(m/s)8.2557.0127.2803.711.87.0447.3604.310.84,,9,B184%118%,101%,B181%B9B9,,BB,10,10,B,B,,B(a)B(b)B(9)9B2891B(a)(b)(9)105讨论,,,,,,ABC,,B,Pareto,,B,6结束语,BB,,,B:[1]MarklundPO,NilssonL.OptimizationofaCarBodyComponentSubjectedtoSideImpact[J].Struct.MultidisciplinaryOptimization,2001,21:383392.[2]ZhuP,ShiYL,ZhangKZ,etal.OptimumDesignofanAutomotiveInnerDoorPanelwithaTailor-weldedBlankStructure[J].JournalofAutomobileEngineering,2008,222(8):13371348.[3]MinKB,KimKS,KangSS.AStudyonResistanceWeldinginSteelSheetsUsingaTailor-weldedBlank(1streport)EvaluationofUpsetWeldabilityandFormability[J].JournalofMaterialsProcessingTechnology,2000,101:186192.[4]ShinJK,LeeKH,SongSI,etal.AutomotiveDoorDesignwiththeULSABConceptUsingStructuralOptimization[J].Struct.MultidisciplinaryOptimization,2002,23:320327.[5]LeeKH,ShinJK,SongSI,etal.AutomotiveDoorDesignUsingStructuralOptimization