S11-1PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation第11部分单元属性S11-2PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation定义单元属性●ElementProperty窗口用来定义:●单元类型和j计算公式●Nastran集中质量,CONM2●ABAQUS体单元标准公式,C3D8●截面属性●0-D:lumpedmass(集中质量),massmatrix(质量矩阵)●1-D:A,Iyy,Izz,J●2-D:thickness(厚度),plateoffset(板的偏移),materialorientation(材料方向)●3-D:material(材料),integrationscheme(积分方法)●应用范围●Geometry几何●FEM有限元●单元特性和几何相关,在重新划分网格后单元特性会重新分配到新的网格上S11-3PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation定义单元属性(续)●定义在几何模型上的属性,当几何被重新划分网格后会自动应用到新的网格上。●单元属性随空间变化可用场来描述,例如thickness=0.10*’Y+0.20*’X**2●属性窗口由求解器,单元类型,和配置确定S11-4PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation创建单元属性●首先,若有必要先选择求解器类型Preferences/Analysis●选择单元维数●0-D(Mass,Spring)●1-D(Beam)●2-D(Shell,2DSolid)●3-D(Solid)●指定名称(最多31个字符)●选择单元选项●在InputProperties窗口中输入属性●和LBCs一样,选择应用区域GeometricentitiesFEMentitiesS11-5PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●数据模板是和求解器,单元类型和配置向关联的●点击MaterialPropName图标,从SelectExistingMaterial窗口中选择列出的材料物理属性输入窗口S11-6PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation物理属性输入窗口(续)●如果有可以使用的场存在,可以选择场。如为Thickness选择场thickness2S11-7PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation物理属性输入窗口(续)●数据项目名称外的方括号表示此项可有选择地输入,如[Non-structuralMass]表明没有非结构质量的输入Patran同样可以运行数据S11-8PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation梁单元属性●Bar/Beamelements需要一个矢量来定义截面的方向(单元坐标系y和z的方向)●在MSC.Patran中,这个矢量可以用全局坐标系(Coord0)或局部坐标系来定义●截面贯性矩I11和I22,以及扭转常数J(不是极贯性矩)是相对与单元坐标系来定义的●为了计算弯曲应力,必须相对于单元坐标系定义应力恢复点●在Nastran中称作C,D,E,F●在计算公式stress=Mc/I中用来确定“c”●Nastran和ABAQUS梁的截面方向将在下页的图中说明S11-9PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation梁单元属性定义例子,Nastran●定义材料属性●输入物理属性参数●应用属性到模型(如面6的第二个边)YXZBeam[截面库的名称]选了材料“Aluminum”通过矢量定义梁(横截面)方向;v1v2v3Coordm在Patran总体坐标系的Y方向上梁截面有–1.5的偏置v1v2v3Coordn梁一端释放的自由度(局部坐标系)在这里调用梁截面库计算A,I11,I22和J.否则,需要手工输入A,I11,I22和J。S11-10PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporationBEAMELEMENTORIENTATION2”JI1MSC.NastranPatranglobalCSNode1Node2ZeYeXe1”I2CDEFZXY001VectorPATRANBarOrientationCoordinatesystemforbeamisXe,Ye,ZePlane1DefinitionofNode1Node2Z,n1YX,t2”JI1ABAQUSVectorZPatranglobalCSXY100PATRANI2n2Coordinatesystemforbeamist,n1,n21”XYPlane**该平面的法向量S11-11PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation梁截面库●可以有选择地创建,查看和保存梁截面●标准梁截面库可以自动计算A,I11,I22,和J●从ElementProperties/InputProperties,或Tools/BeamLibrary中打开BeamLibrary●分配到各单元的梁截面特性可以以图形方式查看●可以对任意形状的梁截面计算截面属性S11-12PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation用BAR单元划分网格举例●构建一个64”x64”加筋板●用quad4单元划分曲面●以Bar2单元划分面的边●用事先定义好的T截面定义梁的属性XYZS11-13PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation显示梁的截面●梁截面和偏移可以使用菜单Display/Load/BC/Elem.Props…显示,在BeamDisplay下选择:例如,3D:FullSpan+OffsetsXYZ●显示实际的截面和方向●只有用BeamLibrary已定义了梁的截面●如果截面是用Area,I1,1,等定义的,则选择…+Equiv.I或AS11-14PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●输入以下几何●File/Import/Neutral.●Selectfour_surfs.out.●Apply.●Turnonsurfacelabelsbyclickingon,then案例学习:用QUADS和BARS划分网格S11-15PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●用IsoMesh划分曲面●SelecttheFiniteElementsApplicationsbutton.●SetAction/Object/TypetoCreate/Mesh/Surface.●SelecttheIsoMeshMesher.●SelectSurface1:4forSurfaceList.●Enter4.0forGlobalEdgeLength.●Apply.●曲面收缩显示,边界就显示出来。●ClickonDisplayinthemainmenu●SelectGeometry…●使用几何收缩显示的滑移条略微作一些收缩显示案例学习:用QUADS和BARS划分网格S11-16PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●模型如下所示案例学习:用QUADS和BARS划分网格S11-17PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●用Bar2类型的单元划分曲面的边界。●SelecttheFiniteElementsApplicationsbutton.●SetAction/Object/TypetoCreate/Mesh/Curve.●SelectBar2Topology.●SelectedgesSurface1.11.32.33.34.3forCurveList.●Enter0.1forGlobalEdgeLength.●Apply.案例学习:用QUADS和BARS划分网格S11-18PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●创建“T”型截面梁的材料。●SelectMaterialApplicationsbutton.●SetAction/Object/MethodtoCreate/Isotropic/ManualInput.●EnterSteelforMaterialName.●ClickInputProperties.●输入ElasticModulus和Poissonratio●OK.●Apply.案例学习:用QUADS和BARS划分网格S11-19PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●对Bar2单元创建梁单元特性●SelectthePropertiesApplicationsbutton.●SetAction/Object/TypetoCreate/1D/Beam.●EnterTeeforPropertySetName.●ClickInputProperties…案例学习:用QUADS和BARS划分网格S11-20PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●输入梁截面特性●SelectSteelfromMatPropNameforMaterialName.●ClicktheICLBeamLibraryicon●EnterTee_csunderNewSectionName,andclickthe“T”button.●Enter3forWidthandHeight.●Enter0.5fort1andt2.●ClickonCalculate/Display.案例学习:用QUADS和BARS划分网格S11-21PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●出现下面的窗口。●ClickOKintheBeamLibrarywindow.案例学习:用QUADS和BARS划分网格S11-22PAT301,Section11,September2010Copyright2010MSC.SoftwareCorporation●定义梁横截面的方向。●UnderInputProperties…Enter001forBarOrientation.●Enter002.07forOffset@Node1.●Enter002.07forOffset@Node2.●OK.案例学习:用QUADS和BA