ANSYS工程分析

《ANSYS工程分析》由会员分享，可在线阅读，更多相关《ANSYS工程分析（49页珍藏版）》请在装配图网上搜索。

1、Chapter 4ANSYS結構分析的基本觀念Basic Concepts for ANSYS Structural AnalysisContents4.1 學科領域與元素類別Disciplines and Element Types4.2 分析類別Analysis Types4.3 線性分析與非線性分析Linear Analysis and Nonlinear Analysis4.4 材料模式Material Models4.5 材料的破壞準則Failure Criteria of Materials4.6 實例:動態分析Example:Dynamic Analysis4.7 實例:非線性分

2、析Example:Nonlinear Analysis4.8 練習題:幾何非線性Exercise:Geometric Nonlinearity2第4.1節學科領域與元素類別Disciplines and Element Types34.1.1 學科領域 結構分析Structural Analysis 熱傳分析Thermal Analysis 流場分析Fluid Dynamic Analysis 電場分析Electric Field Analysis 磁場分析Magnetic Field Analysis 耦合場分析Coupled-field Analysis44.1.2 耦合場分析 Examp

3、le 1:Thermal Stress Analysis Example 2:Structure-Fluid Interactions Example 3:Thermal Actuator54.1.3 元素類別Element Types ANSYS elements are classified according to Discipline Dimensionality Geometry Order Example SOLID45:3D hexahedral linear structural element PLANE67:2D quadralateral linear coupled t

4、hermal-electric element6第4.2節分析類別Analysis Types74.2.1 分析類別Analysis Types Static Analysis Dynamic Analysis Transient Analysis Modal Analysis Harmonic Response Analysis etc.Buckling Analysis Structural Analysis Static,Transient,Modal,Harmonic,Buckling,etc.Thermal Analysis Steady-state,Transient Electr

5、ic Field Analysis Static,Transient,Modal,Harmonic etc.84.2.2 暫態分析Transient Analysis Inertia forces Damping forces Elastic forces External forcesFKDDCDM 94.2.3 靜態分析Static Analysis When dynamic effects can be neglected,a problem can be solved statically.Dynamic effects can be neglected only when the d

6、eformation velocity and acceleration are small.Two cases:Steady-state solution approximation solution for a real-world problem.FKD 104.2.4 模態分析Modal Analysis Modal analysis is to analysis a structure under free vibration.The solutions typically include Vibration frequencies(or periods)Vibration mode

7、s0KDDCDM 114.2.5 諧和反應分析Harmonic Response Analysis Harmonic response analysis is to analysis a structure under periodic excitation of external forces.The solutions typically include maximum responses under various frequencies of external forces12第4.3節線性分析與非線性分析Linear Analysis and Nonlinear Analysis13

8、4.3.1 線性分析Linear Analysis Small deformation Hookes law appies No status or topological changes,eg.,contactsLoadsResponses144.3.2 非線性分析Nonlinear Analysis Geometric nonlinearity Material nonlinearity Status nonlineaity15第4.4節材料模式Material Models164.4.1 材料模式Material Models Material models are mathematic

9、ally represented by a set of equations called constitutive equations.The constitutive equations describe the relations between stresses and strains(or strain rates).The parameters in the constitutive equations are called material parameters.ANSYS provides many material models to be chosen from.174.4

10、.2 彈性與塑性(1/2)Elastic vs.PlasticElastic materials(a)Nonlinear elastic(b)Hysteresis elastic(c)Linear ElasticStressStrain(a)StressStrain(b)(c)StressStrain184.4.2 彈性與塑性(2/2)Elastic vs.PlasticPlastic materialsStrainStress194.4.3 黏滯性與非黏滯性(1/3)Viscous vs.NonviscousNonvisousmaterialsTimeStressTimeStrain204.

11、4.3 黏滯性與非黏滯性(2/3)Viscous vs.NonviscousVisousmaterialsStressStrainTimeTime214.4.3 黏滯性與非黏滯性(3/3)Viscous vs.NonviscousCreepingTimeStressTimeStrainTimeStrainTimeStressStress Relaxation224.4.4 均質性與非均質性材料Homogeneous vs.Heterogeneous A material body is said to be homogeneous if it has uniform material prop

12、erties everywhere in the body.Otherwise it is said to be heterogeneous.Note that,homogeneousness does not necessarily imply isotropy.234.4.5 等向性、非等向性、與正交性材料(1/2)Isotropic,Anisotropic,and Othothropic Materials A material is said to be isotropic if it has the same material properties along any directi

13、ons in the body.Otherwise it is said to be anisotropic.An anisotropic material is said to be orthotropic,if the planes of material symmetry are mutually orthogonal.244.4.5 等向性、非等向性、與正交性材料(2/2)Isotropic,Anisotropic,and Othothropic MaterialsGGGEEEEEEEEEzxzxyzyzxyxyzyxzzyxyzyxxD zxzxzxyzyzyzxyxyxyyyzyx

14、xzxzzzxxyxzzyzyyyzzxzyyxyxxxGGGEEEEEEEEEHookes Law for Isotropic MaterialHookes Law for Anisotropic MaterialHookes Law for Orthotropic MaterialzzxxxzzzyyyzyyxxxyEEEEEE254.4.6 ANSYS材料模式ANSYS Material Models材料分類材料模式名稱非黏滯性材料彈性線性線性彈性材料非線性非線性彈性材料超彈性材料塑性塑性材料黏滯性材料彈性線性線性黏彈材料非線性非線性黏彈材料塑性黏塑性材料26第4.5節材料的破壞準則Fa

15、ilure Criteria of Materis274.5.1 延展性與脆性材料Ductile vs.BrittleDuctile MaterialStrainStressStrainStressBrittle Material284.5.2 脆性材料的破壞準則Failure Criteria for Brittle MaterialsMaximum Principal Stress Failure Criteria:Fracture will occur when tensile stress is greater than ultimate tensile strength,i.e.,u

16、1294.5.3 延展性材料的破壞準則(1/2)Failure Criteria for Ductile MaterialsTresca Failure Criteria:Yielding will occur when shear stress is greater than shear yield strength,i.e.,2231yy31or304.5.3 延展性材料的破壞準則(2/2)Failure Criteria for Ductile Materialsvon Mises Failure Criteria:Yielding will occur when the von Mis

17、es stress is greater than yield strength,i.e.,ye2132322212131第4.6節實例:動態分析Example:Dynamic Analysis324.6.1 問題描述yH=10 mmP=100 NQ=1 MPaxL=60 mmW=6 mmMaterialE=200 Gpan=0.3TimeLoad0334.4.2 ANSYS分析程序(1/6)0102030405060708091011121314151617181920FINISH/CLEARL=0.060H=0.010B=0.006E=200E9NU=0.3RO=7850DMP=0.000

18、1SIZE=0.003Q=1E6P=100/PREP7K,1,0,-H/2,-B/2K,2,0,H/2,-B/2K,3,0,H/2,B/2K,4,0,-H/2,B/22122232425262728293031323334353637383940K,5,L,-H/2,-B/2K,6,L,H/2,-B/2K,7,L,H/2,B/2K,8,L,-H/2,B/2V,1,2,3,4,5,6,7,8/VIEW,1,2,3VPLOTET,1,SOLID45MP,EX,1,EMP,NUXY,1,NUMP,DENS,1,ROMP,DAMP,1,DMPTYPE,1MAT,1ESIZE,SIZEVMESH,ALL

19、FINISH344.4.2 ANSYS分析程序(2/6)42434445464748495051525354555657585960/SOLUNSEL,S,LOC,X,0D,ALL,ALL,0NSEL,S,LOC,Y,H/2SF,ALL,PRES,QNSEL,ALLN1=NODE(L,-H/2,-B/2)N2=NODE(L,-H/2,B/2)F,N1,FY,-P/2F,N2,FY,-P/2ANTYPE,TRANSKBC,1TIME,0.1DELTIM,0.001OUTRES,BASIC,ALLSOLVEFINISH354.4.2 ANSYS分析程序(3/6)62636465666768/POS

20、T1SET,LISTSET,LAST/VIEW,0,0,1PLNSOL,S,XFINISHSETTIMELOADSTEPSUBSTEPCUMULATIVE10.00111120.00212230.003133.1000.1001100100 364.4.2 ANSYS分析程序(4/6)62636465666768/POST1SET,LISTSET,LAST/VIEW,0,0,1PLNSOL,S,XFINISH374.4.2 ANSYS分析程序(5/6)707172737475/POST26NSOL,2,N1,U,Y,UYPLVAR,2PRVAR,2FINISH384.4.2 ANSYS分析程序

21、(6/6)7071727374757677787980/POST26NSOL,2,N1,U,Y,UYPLVAR,2PRVAR,2FINISH/POST1SET,0.002 PLNSOL,S,XTIMEUY0.001-0.00014050.002-0.00019570.003-0.00015330.004-0.00018430.005-0.00016300.006-0.00017630.007-0.00016920.008-0.00017170.009-0.00017240.010-0.0001697.0.100-0.000171439第4.7節實例:非線性分析Example:Nonlinear

22、 Analysis404.7.1 問題描述yH=10 mmP=100 NQ=1 MPaxL=60 mmW=6 mmMaterialE=200 Gpan=0.3414.7.2 ANSYS分析程序(1/6)0102030405060708091011121314151617181920FINISH/CLEARL=60H=10B=6E=200000NU=0.3SY=100ET=0SIZE=3Q=1P=100/PREP7K,1,0,-H/2,-B/2K,2,0,H/2,-B/2K,3,0,H/2,B/2K,4,0,-H/2,B/2212223242526272829303132333435363738

23、394041K,5,L,-H/2,-B/2K,6,L,H/2,-B/2K,7,L,H/2,B/2K,8,L,-H/2,B/2V,1,2,3,4,5,6,7,8/VIEW,1,2,3VPLOTET,1,SOLID45MP,EX,1,EMP,NUXY,1,NUTB,BKIN,1TBDATA,SY,ETTBPLOT,BKIN,1TYPE,1MAT,1ESIZE,SIZEVMESH,ALLFINISH424.7.2 ANSYS分析程序(2/6)4344454647484950515253/SOLUNSEL,S,LOC,X,0D,ALL,ALL,0NSEL,S,LOC,Y,H/2SF,ALL,PRES,

24、QNSEL,ALLN1=NODE(L,-H/2,-B/2)N2=NODE(L,-H/2,B/2)F,N1,FY,-P/2F,N2,FY,-P/25556575859606162636465NSUBST,20OUTRES,BASIC,ALLSOLVENSEL,S,LOC,Y,H/2SF,ALL,PRES,0NSEL,ALLF,N1,FY,0F,N2,FY,0SOLVEFINISH434.7.2 ANSYS分析程序(3/6)676869707172737475/POST1SET,LISTSET,1,LAST/VIEW,0,0,1PLNSOL,S,EQVSET,2,LASTPLNSOL,S,EQVF

25、INISHSETTIMELOADSTEPSUBSTEPCUMULATIVE10.050011220.100012330.175013440.287514550.456315660.709416771.0000171381.0500211591.10002216101.17502317111.28752418121.45632519131.70942620142.00002721444.7.2 ANSYS分析程序(4/6)676869707172737475/POST1SET,LISTSET,1,LAST/VIEW,0,0,1PLNSOL,S,EQVSET,2,LASTPLNSOL,S,EQVFINISH454.7.2 ANSYS分析程序(5/6)676869707172737475/POST1SET,LISTSET,1,LAST/VIEW,0,0,1PLNSOL,S,EQVSET,2,LASTPLNSOL,S,EQVFINISH464.7.2 ANSYS分析程序(6/6)77787980/POST26NSOL,2,N1,U,Y,UYPLVAR,247第4.8節練習題:幾何非線性Exercise:Geometric Nonlinearity48演讲完毕，谢谢观看！