Nastran梁?jiǎn)卧獞?yīng)力輸出

1、1.Nastran梁?jiǎn)卧猯.l.CBAR單元卡片Plane1GridPointGAFigure8-11CBARElementGeometrywithOffsetsGridPointGBPlane1iEndaFigure8-12CBARElementGeometrywithoutOffsetselemCBARSimpleBeamElementConnectionDefinesasimplebeamelement.Format;CBAREIDPIOGAGBXIX2X3OFFTPAPRW1AW2AW3AW1RW2BW3B34567B910Example:CBAR丄39730.6J8.26.GOG5J

2、3AlternateFormat臼ndExample:CBAREIDP1DGAGBGOOFFTW1AW2AW3AW1BW2BW3BCBAR23976105GOG5J3CBAR單元屬性卡PBARLSimpleBeamCross-SectionPropertyDefines(hepropertiesofasimplebeamelement(CBARentry)bycross-sectionaldimensions.PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).F&rmat:234JR-9L0PB

3、ARLSimpleBeamCross-SectionPropertyDefines(hepropertiesofasimplebeamelement(CBARentry)bycross-sectionaldimensions.PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).PBARLSimpleBeamCross-SectionPropertyDefines(hepropertiesofasimplebeamelement(CBARentry)bycross-sectionaldimensio

4、ns.PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).MIDMaterisidentificationnumber.SeeRcmarky2.and3.(Iniegcr0)AI,2,12JAreaofbar工匚口応section.Real;Dcfaulr=0.0)Areamomentscfinertia.SeeFigure8-155.(Real;11孑0.0TL2Q.O3II*121121;Dcfault=fl.0)ForsicnalconslantSeeFigure&-156.(Ftcal;D

5、efault=訶十f訂forSOL6Wand0.0fo-rallotherahtionscqu-cuceiiNSMNonructuramas#perunitlength.(RealCi,Di,Ei,FiStressrecovercDcfUciEnts.(Real:Default=O.d)Areaiactarforshear.SeeFtcmiri5.Real-orblankFormat:234567B9I0PBARLPIDMIDGROUPTYPEDIMDIM2D【M3DIM4DIM5DIMSDIM?DIMEDIM9-etc.-NSMExample:PBARL396I.5.52Fie

6、ldContentsP1DPropertyidentilicaticnnumber.(Integer0)MIDMaterialidentilkaiionnumber.(Integer0)GROUPCross-sectiongroup.SeeRemarks6and8.(Character;Default=(iMSCBML0T1)TYPECross*sectiontype.SeeRemarks6.and8.andFigure8-157.Character:ROD：“TUBE*；“TUBE2篤T,忙HAN篤T；汨OX；FAR*,“CRO5S：H篤“TV,IP；XHANlZ,“CHAN2；T2：“HE

7、XA”，“HAT；“HAT1M,“DBCOTibrGROUP=4LMSCBML0)DIMiCross*sectionaldimensions.(Real0.0forGROUP=“M5CBML(T)NSMNonstrucmralmassperunitlength.NSMisspecifiedafterthelastDIMi.(Default=0.0)Figure6-15ZDefinitionofCnosarSectonGeametardStressRecoveryPointsforGROUP=HMSCBMLDPBARSimpleBeamPropertyDufinusthepropertiesof

8、-asimplebeamelement(匚BARentry).TPE=h,TUBE!,TYPE=HTUBErTYPECHAND|M3XddmTYPE=-BOXnDeternEYPEhROIT-LTYPETFigure8- DefinitionofCross-SectionGeometryandStressRecoveryPointsforGROUPMSCBMLO(continued)PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).1亡kmc-elaoM2TYPEBAR1DIMITPE=/XBD

9、IM1(Ln)-etc.-NSM(m)SO(BinDIM1(B)DIM2(B)-etc.-DIMn(BNSM(B)Example:PBEAML9921T】2M.S2.52.6NO.22.6YESO.G6u7.B5.62.3YESFieldContentsDefaultValues11(A)AreamomentofincrtiaatendAforbendinginplane1abouttheneutralaxis.SeeRemark10.(Real00Required12(A)AreamomentofinertiaatendAforbcndiniginplane2aboutthe

10、neutralaxis.SeeRemark10.(Real0.0)Required112(A)0.0.AreaproductofinertiaatendA.SeeRemark10.(FtcaLbut/-/2-/!2)2o)J(A)ToisidJialstiffnessparameteratend.A.SeeRemark0兔111(=+気+A)for10.(Real0.0but0.Cifwarpingispresent)SOLMOand.0.0forallothersaluticmsoquenresNSM(A)Noastructunimassperunitlength,atendA.(Real!

11、0.0Ci(A|.Di(A、TheyandzlocaTions(i=1canrcspondstoyand.i=2correspondstoz)inelementcoordinatesy=1=0.0Ei(A),Fi0.0)SeeRemark6.A,l.12,112,Area,momentsofinertia,torsionalstiffnessparameter,andnDnstructura.torthecrossSeeRemark7.J,NSMsectionlocatedatx.(Real;J0.0ifwarpingispresent-Ci,Di,EinFiTheyandzlocaTions

12、(i=1canrcspondstoyand.i=2contpuiiLhLuz)inlnint仁口幹ixli口Elc西relativetotheshearcenter(呂eeFigure8=163inRemark-10.)forrhecrossectionlocatedatX-XR.Thevaluesarcfiberlocationsforstressdatarecovery.Ign-orcdforbeamp-tlcmcnts.(Real)PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).JTYP

13、E=E,RODBPTYPE=C,TUBE2PPdemTYPEs-FTYPE=-CHAN,PPBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).TYPE=C,TUBE,:,DIM4DIM3TYPE=MCRO5SSPPBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).TYPE=*BAR1BDl2DIW4DIM1TYPEaz-H-TYPE*疋“TYPE-CHANa1-PBARSimpleBeamProper

14、tyDufinusthepropertiesof-asimplebeamelement(匚BARentry).DIM4FTYPE-Tr10.5DIMIlekm0.5DMITYPE-Llir,TYPE=LICHAN1,rPBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).丄ItemtfcmTYPE=E,T2TYPEsBOXFTYPE寸HAT”IMSDMTYPE=*HAT13PTYPEE,HEXA1PDIMSPBARSimpleBeamPropertyDufinusthepropertiesof-as

15、implebeamelement(匚BARentry).DIMSDIM7IM9DIMWTYPE=JDBOXTDIM7Figure8-164DefinitionofCrts-SectioriGeometryandStressRecoveryPoinlsforGROUP=MSCBML0IM2IM2PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).2.N

16、astran梁?jiǎn)卧獞?yīng)力輸出一維梁?jiǎn)卧械膬?nèi)力或應(yīng)力可以通過(guò)單元力或單元應(yīng)力輸出（如FORCE或者ELFORCE）來(lái)進(jìn)行輸出，并且梁?jiǎn)卧惠敵鰬?yīng)力恢復(fù)點(diǎn)的應(yīng)力。如果梁截面是標(biāo)準(zhǔn)庫(kù)中的截面（PBARL，PBEAML定義的截面），則應(yīng)力恢復(fù)點(diǎn)已經(jīng)由程序根據(jù)不同的截面形狀進(jìn)行定義，不需要用戶定義。如果是自己定義的梁截面（PBAR,PBEAM定義的截面），則用戶必須自行定義應(yīng)力恢復(fù)點(diǎn)（屬性卡片中的C1,C2、D1,D2、E1,E2、F1,F2）。此時(shí)beamelements的應(yīng)力需要選擇recoverypointonthebeamcrosssection，然后在stressrecoverypointC/

17、D/E/F-Element-Nodal中可以看到對(duì)應(yīng)的應(yīng)力分析結(jié)果。2.1.CBAR梁?jiǎn)卧膯卧蛻?yīng)力下圖是CBAR梁?jiǎn)卧Γ╡lementforce）的正方向。real或者complex形式（取決于輸出格式）的單元力的輸出包括下面幾項(xiàng)：PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).GridPointGAFigure8-11CBARElementGeometrywithOffsetsPBARSimpleBeamPropertyDufinusthepropertiesof-asimplebe

18、amelement(匚BARentry).yM1a,M1b,M2a和M2b是分別在兩個(gè)參考平面中，兩個(gè)端點(diǎn)處的彎矩。V1和V2是在兩個(gè)參考平面中的剪力，F(xiàn)x是平均的軸向力，T是繞x軸的扭矩。輸出中可以要求輸出CBAR單元下面的real形式單元應(yīng)力(elementstress)：平均軸向應(yīng)力(averageaxialstress)：axialstress由在兩個(gè)端點(diǎn)A、B處橫截面上的4個(gè)應(yīng)力恢復(fù)點(diǎn)的彎矩引起的張性應(yīng)力(extensionalstressduetobending)：SA1、SA2、SA3、SA4，SB1、SB2、SB3、SB4。僅當(dāng)用戶在PBAR卡片中輸入了應(yīng)力恢復(fù)點(diǎn)，才計(jì)算該彎曲

19、應(yīng)力。兩個(gè)端點(diǎn)A、B處的最大和最小的張性應(yīng)力(maximumandminimumextensionalstressatbothends)：SA-MAX、SA-MIN、SB-MAX、SB-MIN。該最大和最小的張性應(yīng)力是由每端軸向應(yīng)力和彎曲張性應(yīng)力的合成。拉伸安全系數(shù)和壓縮安全系數(shù)(Marginsofsafetyintensionandcompression)。僅當(dāng)用戶在MAT1卡片中輸入了應(yīng)力極限(stresslimits)時(shí)，才計(jì)算該安全系數(shù)。拉伸應(yīng)力為正值，壓縮應(yīng)力為負(fù)值。只有平均軸向應(yīng)力和彎曲張性應(yīng)力可以是復(fù)數(shù)應(yīng)力(complexstrss)。對(duì)于梁?jiǎn)卧膽?yīng)力輸出，patran04中有以

20、下選項(xiàng)：軸向(barstresses,axial)(atcenter)barstresses，bendingposition(AtpointCDEF)最大、最小合成(atcenter)Maxshear在Hyperview后處理Nastran的CBAR單元時(shí)，梁?jiǎn)卧狢BAR中的單元力和單元應(yīng)力的輸出如下：elementIDSA1SA2SA3SA4AXIALSTRESSSA-MAXSA-MINM.S.-T(safetymargintension)SB1SB2SB3SB4SB-MAXSB-MINM.S.-C(safetymarginCompression)其中：A,B表示梁的兩個(gè)端面。1-4是用戶指

21、定的用來(lái)計(jì)算應(yīng)力的截面上的四個(gè)點(diǎn)。SA1-SA4，SB1-SB4是僅由純彎曲所引起的正應(yīng)力(NormalStressDuetoBendingOnly)，AXIALSTRESS是僅有軸向載荷所引起的正應(yīng)力(NormalStressDuetoAxialLoadOnly)，SA-MAX，SA-MIN，SB-MAX，SB-MIN是彎曲與軸向載荷組合情況下的兩個(gè)端面的最大、最小正應(yīng)力(CombinedAxialandBendingStress)。M.S.-T是拉伸安全系數(shù)，M.S.-C是壓縮安全系數(shù)。2.2.CBEAM梁?jiǎn)卧膯卧蛻?yīng)力EndA(0,0f0)NeutralAxis亂offsstGrid

22、PointGA3勿淪1珞紐勿/?NonstructuralMassCenterofGravityShearCenterEndR(陽(yáng)0.0)offsetGridPointGBYmb|忙IzribFigure8-15CBEAMElementGeometrySystem(Nonp-adaptive)PBARSimpleBeamPropertyDufinusthepropertiesof-asimplebeamelement(匚BARentry).lemYelemxeleinFigure8-17CBEAMInternalElementForcesandMomentsCBEAM單元的應(yīng)力輸出與CBAR單

23、元有些不同。對(duì)于CBAR單元，SAi和SBi列只是彎曲應(yīng)力，而軸向應(yīng)力單獨(dú)列出。但是對(duì)于CBEAM單元，SXC、SXD、SXE和SXF是在CBEAM中橫截面上應(yīng)力恢復(fù)點(diǎn)C、D、E、F處的彎曲應(yīng)力和軸向應(yīng)力的組合。在CBEAM的每個(gè)端點(diǎn)進(jìn)行應(yīng)力恢復(fù)，還可以在任何由PBEAM輸入卡片確定的中間位置進(jìn)行應(yīng)力恢復(fù)。在Hyperview后處理Nastran的CBEAM單元時(shí)，梁?jiǎn)卧狢BEAM中的單元力和單元應(yīng)力的輸出如下：CBEAMlongCBEAMlongCBEAMlongCBEAMCBEAMCBEAMmarginofsafetytension1marginofsafetystressatstressatstressatpointlongstre