Chapter 9 2D 實體結構分析 Analysis of 2D Structural Solids.

Chapter 9

2D實體結構分析Analysis of 2D Structural Solids

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Contents9.1 何謂 2D結構 ?

When is a Structure Modeled as 2D?

9.2 PLANE42: 2D實體結構元素PLANE42: 2D Structural Solid Element

9.3 實例 : 平面應力問題Example: Plane Stress Case

9.4 實例 : 平面應變問題Example: Plane Strain Case

9.5 實例 : 軸對稱問題Example: Axisymmetric Case

9.6 2D實體元素瀏覽Overview of 2D Solid Elements

9.7 練習題 : 懸臂樑的 2D分析2D Analysis of a Cantilevel Beam

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第 9.1節

何謂 2D結構 ?When is a Structure Modeled as 2D?

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9.1.1 平面應力問題0 zyyzzxxzz

EE

G

EE

EE

yxz

zyyzzxxz

xyxy

yxy

yxx

0Fixed pin hole, 0.8 in diameter

Tapered pressure load: 50 to 500 psi approximates a 130 lb pin load force

6 in

2 in

4 in

2 in

0.4 in radius

Thickness = 1/2 in

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9.1.2 平面應變問題0 zyyzzxxzz

yxz

zyyzzxxz

xyxy

yxy

yxx

E

G

E

E

211

0

1211

1211

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9.1.3 軸對稱問題0 yyrr

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第 9.2節

PLANE42: 2D實體結構元素PLANE42: 2D Structural Solid Element

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9.2.1 PLANE42元素描述

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9.2.2 PLANE42輸入資料Element Name PLANE42

Nodes I, J, K, L

Degrees of Freedom UX, UY

Real Constant None, if KEYOPT (3) = 0, 1, 2Thickness, if KEYOPT (3) = 3

Material Properties EX, NUXY, GXY, ALPX, DENS, DAMP, etc.

Surface Loads Pressure: face 1 (JI), face 2 (KJ), face 3 (LK), face 4 (IL)

Body Loads Temperature -- T(I), T(J), T(K), T(L)

Special Features Plasticity, Creep, Stress stiffening,Large deflection, Large strain, etc.

KEYOPT(1) Key for element coordinate system:0 -- Element C.S. is parallel to the global C.S.1 -- Element C.S. is based on the element I-J side

KEYOPT(2) Key to include extra shapes:0 -- Include extra displacement shapes1 -- Suppress extra displacement shapes

KEYOPT(3) 0 -- Plane stress1 -- Axisymmetric2 -- Plane strain3 -- Plane stress with thickness input

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第 9.3節

實例 : 平面應力問題Example: Plane Stress Case

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9.3.1 問題描述

Fixed pin hole, 0.8 in diameter

Tapered pressure load: 50 to 500 psi approximates a 130 lb pin load force

6 in

2 in

4 in

2 in

0.4 in radius

Thickness = 1/2 in

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9.3.2 ANSYS Procedure (1/5)01

02

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FINISH

/CLEAR

/TITLE, Corner Bracket (in-lbf-s)

/PREP7

ET, 1, PLANE82,,, 3

R, 1, 0.5

MP, EX, 1, 30E6

MP, NUXY, 1, 0.27

RECTNG, 0, 6, -1, 1

RECTNG, 4, 6, -3, -1

PCIRC, 1

WPOFFS, 5, -3

PCIRC, 1

AADD, ALL

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WPOFFS, -5, 3

PCIRC, 0.4

WPOFFS, 5, -3

PCIRC, 0.4

ASBA, 5, ALL

LFILLT, 8, 17, 0.4

AL, 12, 13, 14

AADD, ALL

APLOT

/PNUM, LINE, ON

/PNUM, KP, ON

LPLOT

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31

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/PNUM, DEFAULT

SMRTSIZE, 5

AMESH, ALL

EPLOT

FINISH

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/SOLU

DK, 7, ALL, 0,, 1

DK, 9, ALL, 0,, 1

DK, 10, ALL, 0,, 1

DK, 12, ALL, 0,, 1

SFL, 10, PRES, 50, 500

SFL, 11, PRES, 500, 50

/PBC, U,, ON

/PSF, PRES, NORM, 2

APLOT

SOLVE

FINISH

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51

52

53

/POST1

PLDISP, 2

PLNSOL, S, EQV

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第 9.4節

實例 : 平面應變問題Example: Plane Strain Case

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9.4.1 問題描述

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FINISH

/CLEAR

/TITLE, STRESSES IN A LONG CYLINDER

/UNITS, BIN

/PREP7

ET, 1, PLANE42,,, 2

MP, EX, 1, 30E6

MP, DENS, 1, .00073

MP, NUXY, 1, 0.3

CSYS, 1

K, 1, 4, 0

K, 2, 8, 0

K, 3, 4, 45

K, 4, 8, 45

A, 3, 1, 2, 4

ESIZE, .25

MSHKEY, 1

MSHAPE, 0, 2D

AMESH, 1

NROTAT, ALL

FINISH

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/SOLU

NSEL, S, LOC, Y, 0

NSEL, A, LOC, Y, 45

D, ALL, UY, 0

NSEL, S, LOC, X, 4

SF, ALL, PRES, 30000

ALLSEL

/PBC, U,, ON

/PSF, PRES, NORM, 2

EPLOT

SOLVE

NSEL, S, LOC, X, 4

SF, ALL, PRES, 0

ALLSEL

OMEGA,,, 1000

SOLVE

FINISH

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/POST1

SET, 1

PLDISP, 2

RSYS, 1

PLNSOL, S, X

PLNSOL, S, Y

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9.4.2 ANSYS Procedure (4/6)

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PATH, R-DIR, 2

PPATH, 1,, 4, 0

PPATH, 2,, 8, 0

PDEF, R-STRESS, S, X

PDEF, H-STRESS, S, Y

/GRID, 1

/AXLAB, Y, STRESS

/TITLE, STRESS UNDER PRESSURE

PLPATH, R-STRESS, H-STRESS

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SET, 2

PLDISP, 2

PLNSOL, S, X

PLNSOL, S, Y

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PDEF, H-STRESS, S, Y

/TITLE, STRESS UNDER ROTATION


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第 9.5節

實例 : 軸對稱問題Example: Axisymmetric Case

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9.5.1 問題描述

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FINISH

/CLEAR

/TITLE, STRESSES IN A LONG CYLINDER

/UNITS, BIN

/PREP7

ET, 1, PLANE42,,, 1

MP, EX, 1, 30E6

MP, DENS, 1, .00073

MP, NUXY, 1, 0.3

K, 1, 4, 0

K, 2, 8, 0

K, 3, 4, 1

K, 4, 8, 1

A, 3, 1, 2, 4

ESIZE, .25 MSHK, 1

MSHA, 0, 2D

AMESH, 1

FINISH

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/SOLU

NSEL, S, LOC, Y, 0

NSEL, A, LOC, Y, 1

D, ALL, UY, 0

NSEL, S, LOC, X, 4

SF, ALL, PRES, 30000

ALLSEL

/PBC, U,, ON

/PSF, PRES, NORM, 2

EPLOT

SOLVE

NSEL, S, LOC, X, 4

SF, ALL, PRES, 0

ALLSEL

OMEGA,, 1000

SOLVE

FINISH

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/POST1

SET, 1

PLDISP, 2

PLNSOL, S, X

PLNSOL, S, Z

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9.5.2 ANSYS Procedure (4/6)

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PATH, R-DIR, 2

PPATH, 1,, 4, 0

PPATH, 2,, 8, 0


PDEF, H-STRESS, S, Z

/GRID, 1

/AXLAB, Y, STRESS

/TITLE, STRESS UNDER PRESSURE


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SET, 2

PLDISP, 2

PLNSOL, S, X

PLNSOL, S, Z

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PDEF, H-STRESS, S, Z

/TITLE, STRESS UNDER ROTATION


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第 9.6節

2D實體元素瀏覽Overview of 2D Solid Elements

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9.6.1 General 2D Structural Solids

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9.6.2 Axisymmetric Harmonic Solids

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9.6.3 Large Strains

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9.6.4 P-Elements

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9.6.5 Hyperelasticity

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9.6.6 Viscoelasticity and Viscoplasticity

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9.6.7 Thermal Solids

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9.6.8 Axisymmetric Harmonic Thermal Solids

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9.6.9 Fluid Elements

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9.6.10 Electrostatic Fields

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9.6.11 Magnetic Fields

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9.6.12 Coupled-Field Elements

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第 9.7節

練習題 : 懸臂樑的 2D分析2D Analysis of a Cantilever Beam

Chapter 9 2D 實體結構分析 Analysis of 2D Structural Solids.

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Transcript of Chapter 9 2D 實體結構分析 Analysis of 2D Structural Solids.