Nastran梁单元应力输出

1、word格式1. Nastran梁单元 1.1. CBAR单元卡片Plane 1Grid Point GBEnd bPlane 2Grid Point GAFigure 8-11 CBAR Element Geometry with OffsetsFigure 8-12 CBAR Element Geometry without OffsetsCBARSimple Beam Element ConnectionDefines a simple beam element.Format:I234567S910CBAREIDPIDGAGBXIX2X3OFFTPAPBW1AW2AW3AW1BW2BW3

2、BExample:CBAR239730.626.GOG513Alternate Format and Example:CBAREIDPIDGAGBGOOFFTPAPBW1AW2AW3AWLBW2BW3BCBAR23976105GOG513CBAR单元属性卡PBARSimple Beam PropertyDefines the propenics of a simple bcaniekmcRt (CHAR entry).Format:PIDProperty identification number. (Integer 0)MIDMaterial identification nurnber S

3、ec Remarks 2 and 3. (Integer 0)AArea of bur cross section, f Real: Default = 0.0)I1T 12, 112Area moments of inertia. Sec Figure 8-l56t (Real； I 0.0T 12 0_0*【I *12 I121;Dchuill = GO)JTorsional constant, S Figure 8-156. (Real: Default =+ /J fw SOL 600 and0.0 for all other solution sequences)NSMNonstru

4、ciural mass per unit length. Realf DI EL FiStress rccoyery cue flic ienbi. (Real： Default 0.0)KLK2Area fhetor for shear, See Remark 5 (Real or blank)word姦幵PBARLsimp-e BetDrn C3SVIseaon PropertyDefine? -he papertiCJR afnmpobetun eQmofnCHR cmry) by crew屮 seciiomd dimelo-ny5FonnFt:pMNExamp-e43 g护6LhUhU

5、sthik?Fi2.d00337HD MID ghol-tProperty i&nmicarion rmmber*(bier V 9 Merial ide口tifk 世tie-n number (mte 帕er scrogT豐 ciion gnxlT1See ReTnnTks; 6- and m- (characlen De find i M ;MTYPE CYo 牟 sc2knl -ype See Remarks 6 and 8 smd Figure 匸57二01：ROD 3BEJ * TU0E2 J T：CHAN,JT；BUXTBARJ TCROSSJ ；TT 丄二 FCHAN 二 z+

6、占HANH八 42川 GWOX7 HEXXAT45H5 :DBOX: fbr GROUPlMSCBMLfrjNicrofimcno 竄一 dime 孚ortl 尹(Rea 一 0.0r GROUP MSCBMLO:)NMM Nonilnjctu 邑 tna 熬 per UE.二怙 nrr?NSM 席 Jipecsed Dftcr ihe 一男 t d-ml5word格式TYPEsROD1JTYPETUBE?TYPE=,LTUeEMDIMITfPE=TTYPE=BOX-Figure 8-157 Definition of Cross-Section Geometry and Stress Rec

7、overy Points for GROUP = MSCBMLO1 elanYDi 袖TPE=,+BARTYPE-TV1TYPE MV*Figure 8*158 DefiniUon of Cross-Section Geometry and Stress Recovery Points for GROUP 二MSCeMLO (continued)4cDTYPEs-CHANVFigure 3-159 Definition of Cross-Sect ton Geometry and Stress Recovery Points forGROUP = “MSC吕站L(continued)rypE=

8、”BmcrQ0aln&lu.tlllAOOuMEnMHIIS pue aaLUOuCJ匚 0QUUS 由 SQJiJ一 o uo=uk=uu壬一 0435 IL-VX3H电亡咚 po/vword格式1.2. CBEAM单元卡片End A (0, 0, 0)i?Lf offsetNon structural MassCenter of Gravity妙ZPimn詐湖迤务彩ZNeutral Axiselemv_Grid Point GAEnd B(xb )Grid Point GBFigure 8-15 CBEAM Element Geometry System (Non p-adaptive)C

9、BEAMBeam Element ConnectionDefines a beam clemenLFormat：CBEAMEIDPIDGAGBXIX2X3OFFT/B1TPAPBW1AW2AW3AW1BW2BW3BSASB2345678910Example:CBEAM2397138.2&1-5.6GOG5133.0耳5Alternate Format and Example:CBEAMEIDPIDGAGBGOOFFT/BITPAPBW1AW2AW3AW1BW2BW3BSASBCBEAM239713105GOG513CBEAM单元属性卡(1) PBEAM属性卡PBEAMBeam Property

10、Deli nes the properties of a bc;im ekmenl (CBHAM entry). This element may be used to model tapered beams.Format:7R910PBEAMP1DMIDA(A)n(A12(A)112(A)J(A)NSM(A)Cl (A)C2(A)DI (A)D2(AEl (A)E2(A)Fl (A)F2(A)The next twoconiinuaiions arc repeated tbr each intermediate station as described in Remark 6 and SO

11、and X XB tniihi be specifkd.SOX/XBA112112JNSMClC2DID2ElE2FlF2The last two continuations are:KLK2SIS2NS1A)NS(B)CW(ACW(B)MI(A)M2A)Ml(B)M2(B|Nl(A)N2(A)Nl(B)N2(B)Example:Tapered beam with A=2.9 al end A and A=5.3 at end B.PBEAM3972.040YESL.O5.356.278.62.5-5.014(2) PBEAML属性卡PBEAMLBe

12、am CrossSection PropertyDefines ihe- properties of a beam element by cross-sectia nnl dime nsdons.Format:(Note: n = number of dimcmions and tn = number ofintcnnediaic Nations)1234567K9I0PBEAMLPIDMIDGROUPTYPEDIM 1( A)DIM2(A)YtG-D(Mn(ANSM(A)SCXUX| 1) XBD1M2H J-etc.-DIMiill)1SSM(1SO(打X(2yXBDIM 1(2)D1M2

13、(2)-etc.-DJMn(2)NSMfm-etc.-SO(m)X(ni)CXBDFMKni)-etc.-DIMnim)USM(m)SO(B)LODIM 1(B)-etc.-D1Mn(B)NSM(B)Example:PBEAML鼻921112tNO0.46.7-122.6YES0.67.S5.623YESFieldContentsDefauH Values11 (A)Area moment crinenh nt end A for bending inplane J about the nculnil axis. See Rciiuirk 10 (Rl 0.0)Requir

14、ed2(A)Area moment cf inertia lit end A for bending inplane 2 abcut the riculml axis. See R.cniark 10 (Real 0.0)Required112(A)0,0, Area product of inertia at nd A. See Remark10. (Kcal, but ;i - 72 - ifii) do )JlA)Torsional stiffness parameter at end. A. See RemarkDefaut=(/: + i, i Jur10 (Real OlQ but

15、 0.0 if waqnng ii present)SOL 600 and 0. 0 for all other solution sequencesNSM1A)Nonstruclunil mass per unit length, at end A. (Real)0 0CKAXDi(A)The y and 1 local ions (i - I corresponds to y md i = 2 corrcsponck io in elcmcTit coordinatesy = z = 0.UEKA)t Fi(A)rchlive to the shear center (see the di

16、agram (bl lowing lhe remarks | it end A for stress chu recovenr- (Rea)SOStress output request opticn. See Remark 9_ (Charactcr)hbYES Siresscs recovered at pcinl百 Ci, Di. Ei. and Fi on the next continmalion.YES AT Stresses recovered at points with the same y and z location as end A.KO7” No stresses o

17、r forces are recovered.Required*X XBDistance from end A in the element courdinalLcRequired*system divided b lhe lengih of the element SeeFigure 8-163 in Remark 10. Real a Q.O)See Reniiirk 6.Area. mamenLs of inertia, torsiional stiffness parameter, and nonslmclural mi湘 for itic crossSec Remark 1J. NS

18、Msectian located al x. (Real; J 0.0 if warping is present. JCi, DL Ei, FtThe y and i Ig2liu阳(i I corrcNponds io y and i = 2 con-espondls io z) in element coordinate rchlivc to the shear center (see Figure 8163 in Remark 10 J for the cross 沖:lion hxraled at X XB. The values are fiber locations for st

19、ress data recovery. Ignarcd Ibr bcm p-clmcnts. (Rcoil|iJdemETYPE- ROD 1TYPE-lLTUBEnDM2TYPE- TUBE2$如DIM3IYPE-T1TfPE L曲 DIM4DIM3 | Vutwi2=taDIM1 TYPEJdCHAN1 ckiftDDIM3 *If ITYPE-BOX1*TYPE-BAR1DIM2TYPECROSS11TYPE-Hword姦幵LM亠3TYPEH =TYPE*”-rrD_M2 c-TYPT6HAN-Sr孑TYPEEZ TYPT-riHANhlM.AlVH.i-SdAl L 刊 KJVNIOz

20、nia.IVHp-adAl LXOSr =3dAl.YXaH-BdAl.in-adAi聊魁PJOMword格式DIM7DIM7IMSDIM9DIM?DIM?DIM10TYPE = TBOXFigure 8-164 Definition of Gross-Section Geometry and Stress Recover Points for GROUP =4,MSCBMLOn2. Nastran梁单元应力输出一维梁单元中的内力或应力可以通过单元力或单元应力输出（如FORCED者ELFORCE来进行输出，并且梁单元只输出应力恢复点的应力。如果梁截面是标准库中的截面（PBARL PBEAML定

21、义的截面），则应力恢复点已经由程序根据不同的截面形状进行定 义，不需要用户定义。如果是自己定义的梁截面（PBAR PBEAM定义的截面），贝U用户必须自行定义应力恢复点（属性卡片中的C1,C2 D1,D2、E1,E2 F1,F2 此时 beam elements 的应力需要选择 recovery point on the beam cross section, 然后在 stress recovery point C/D/E/F- Eleme nt-Nodal中可以看到对应的应力分析结果。2.1. CBAR梁单元的单元力和应力下图是CBAR梁单元力（element force）的正方向。real

22、或者complex形式（取决于输出格式）的单元力的输出包括下面 几项：Grid Point GAFigure 8-11 CBAR Element Geometry with OffsetsaPlane 1bzr2Figure 3-7 CBAR Element ForcesM1a, M1b, M2a和M2b是分别在两个参考平面中，两个端点处的弯矩。V1和V2是在两个参考平面中的剪力，Fx是平均的轴向力，T是绕x轴的扭矩。输出中可以要求输出 CBAR单元下面的real形式单元应力（eleme nt stress）：（1）平均轴向应力（ average axial stress : axial st

23、ress（2） 由在两个端点A、B处横截面上的4个应力恢复点的弯矩引起的张性应力（exte nsio nal stress due to ben di ng）： SA1、 SA2、 SA3 SA4, SB1、 SB2 SB3 SB4仅当用户在PBAR卡片中输入了应力恢复点，才计算该弯曲应力。(3) 两个端点 A、B 处的最大和最小的张性应力(maximum and minimum extensional stress at both ends): SA-MAX SA- MIN 、SB-MAX SB-MINo该最大和最小的张性应力是由每端轴向应力和弯曲张性应力的合成。(4) 拉伸安全系数和压缩安

24、全系数(Margins of safety in tension and compression。仅当用户在 MAT1卡片中输入了应力 极限(stress limits)时，才计算该安全系数。拉伸应力为正值，压缩应力为负值。只有平均轴向应力和弯曲张性应力可以是复数应力(complex strss)。对于梁单元的应力输出，patran04中有以下选项：(1) 轴向(bar stresses ,axiaj (at center)(2) bar stresses bending position( At point C D E F(3) 最大、最小合成(at center)(4) Max shear

25、在Hyperview后处理Nastran的CBAR单元时，梁单元CBAR中的单元力和单元应力的输出如下：eleme nt IDSA1SA2SA3SA4AXIALSTRESSSA-MAXSA-MINM.S.-T (safety margin tension)SB1SB2SB3SB4SB-MAXSB-MINM.S.-C (safety marginCompression)其中：A,B表示梁的两个端面。1-4是用户指定的用来计算应力的截面上的四个点。SA1-SA4 SB1-SB4是 仅由纯弯曲所引起的正应力(Normal Stress Due to Ben di ng Only)AXIAL STRE

26、SS 仅有轴向载荷所引起的正应力 (Normal Stress Due to Axial Load On ly)SA-MAX SA-MIN, SB-MAX SB-MIN是弯曲与轴向载荷组合情况下的两个端面的最大、最小正应力(Comb ined Axial a ndBending Stress)M.S.-T是拉伸安全系数，M.S.-C是压缩安全系数。End A (0, 0, 0)i?Lf offset22 CBEAM梁单元的单元力和应力Nonstructural Mass Center of Gravity.妙ZPimn詐湖遂參多2Neu帕I AxiselemvGrid Point GAEnd

27、B(xb )Grid Point GBFigure 8-15 CBEAM Element Geometry System (Non p-adaptive)lem/ZZ/ZZZZZZ/ zzzzzzzz/ ZZ/ZZ2 /zz/ZZZZZ/ zzzzzzz zzzzzzzzz /yelern召 Neutral Axis11 ,xelemShear CenterFigure 8-17 CBEAM Internal Element Forces and MomentsCBEAM单元的应力输出与CBAF单元有些不同。对于 CBAR单元，SAi和SBi列只是弯曲应力， 而轴向应力单独列出。但 是对于CBEAM单元，SXC SXD SXE和 SXF是在CBEAM中横截面上应力恢复点 C、D、E、F处的弯曲应力和轴向应力的组合。在CBEAM的每个端点进行应力恢复，还可以在任何由 PBEAM输入卡片确定的中间位置进行应力恢复 在Hyperview后处理Nastran的CBEAM单元时，梁单元CBEAM中的单元力和单元应力的输出如下：eleme ntIDCBEAM long stress at poi nt C1CBEAM long stress at po