Collection_Abaqus.pdf

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Abaqus/CAE

(ver. 6.11)

Shell Tutorial

Problem Description

The aluminum arch (E = 70 GPa, ν = 0.3) shown below is completely clamped along the flat faces. The arch

supports a pressure of 100 MPa.

In this example, we also practice how to mesh a “portion” of geometry and how to avoid modeling

unnecessary segments!

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Analysis Steps

1. Start Abaqus and choose to create a new model database

2. In the model tree double click on the “Parts” node (or right click on “parts” and select Create)

3. In the Create Part dialog box (shown above) name the part and a. Select “3D”

b. Select “Deformable” c. Select “Shell” d. Select “Extrusion”

e. Set approximate size = 100 f. Click “Continue…”

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b. Set Depth = 10 c. Click “OK”

5. Double click on the “Materials” node in the model tree

a. Name the new material and give it a description b. Click on the “Mechanical” tabÎElasticityÎElastic

c. Define Young’s Modulus and the Poisson’s Ratio (use SI (mm) units)

i. WARNING: There are no predefined system of units within Abaqus, so the user is responsible for ensuring that the correct values are specified

ii. See the table of consistent units below

Quantity

SI

SI (mm)

US Unit (ft) US Unit (inch)

Length m

mm

ft

in

Force N

N

lbf

Mass kg

tonne

(10

3

kg)

slug

lbf s

2

/in

Time s

s

Stress Pa

(N/m

2

) MPa (N/mm

2

)

lbf/ft

2

psi

(lbf/in

2

)

Energy J mJ

(10

–3

J)

ft lbf

in lbf

Density kg/m

3

tonne/mm

3

slug/ft

3

lbf

s

2

/in

4

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a. Name the section “shell_properties” and select “Shell” for the category and “Homogeneous” for the type

b. Click “Continue…”

c. Select the material created above (aluminum) and set the thickness to 1 (mm). d. Adjust the thickness integration points if necessary

i. For Simpson integration the number of points must be odd and between 3 and 15 ii. For Gauss integration the number of points must be between 2 and 15

e. Click “OK”

7. Expand the “Parts” node in the model tree, expand the node of the part just created, and double click on “Section Assignments”

a. Select the entire geometry in the viewport and press “Done” in the prompt area b. Select the section created above (shell_properties).

c. Specify shell offset if necessary. For this example use the default of “middle surface”. d. Click “OK”

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a. Select all faces and click “Done”

b. Select one of the flat faces as the sketch plane

c. Specify “Through All” for the projection distance. Note the arrow should encompass the entire part. d. Select “Flip” if the arrow showing the project direction is incorrect, and/or press “OK”

e. Select one of the edges on the end of the part as the vertical sketch direction

f. Create a sketch that will divide the part into quarters. For example: draw a vertical line, select the equal distance constraint, pick the node at the upper right, pick the node at the upper left, then pick the drawn vertical line. The constraint will move the line to the midpoint.

g. Select “Done”

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a. Select “Dependent” for the instance type b. Click “OK”

10. Save the model

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a. Name the step, set the procedure to “General”, and select “Static, General” b. Give the step a description

12. Expand the History Output Requests node in the model tree, and then right click on H-Output-1 (H-Output-1 was automatically generated when creating the step) and select Delete

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was automatically generated when creating the step) a. Uncheck the variables “Strains” and “Contact”

14. Because the part is symmetrical and the flat surfaces are fully restrained only a quarter of the arch needs to be modeled.

15. Because the flat surfaces are assumed to be fully restrained we do not need to include them, and can instead fix just the edge.

16. Double click on the “BCs” node in the model tree

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c. Select “ENCASTRE” for the boundary condition and click “OK”

Note:

Restraining the entire surface will be inefficient, requiring

unnecessary meshing of the portion of the geometry which will have

no influence on the stiffness properties, and thus the result of

simulation. Therefore, the restraint is applied to the shown edge to

reduce the problem size. Noting this, the geometry creation could

have been simplified right from the start!

a. Name the boundary conditioned “Zsymm” and select “Symmetry/Antisymmetry/Encastre” for the type

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d. Repeat for the other edge and select “Xsymm” to apply x-dir symmetry condition. 18. Double click on the “Loads” node in the model tree

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c. Select the color corresponding to the top surface d. For the magnitude enter 600

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Element Type” icon

a. Select the portion of the geometry associated with the boundary conditions and load b. Select “Standard” for element type

c. Select “Linear” for geometric order d. Select “Shell” for family

e. Note that the name of the element (S4R) and its description are given below the element controls f. Select “OK”

20. In the toolbox area click on the “Assign Mesh Controls” icon a. Select the portion of the geometry

associated with the boundary conditions and load

b. Change the element shape to “Quad”

21. In the toolbox area click on the “Seed Edges” icon

a. Select the shorter edges of the portion of the geometry associated with the boundary conditions and load

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boundary conditions and load ii. Specify 10 elements

c. Select “Done”

22. In the toolbox area click on the “Mesh Region” icon

d. Select the portion of the geometry associated with the boundary conditions and load e. Select “Done”

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a. Name the job “arch_linear_static” b. Give the job a description

24. In the model tree right click on the job just created (arch_linear_static) and select “Submit” f. Ignore the message about unmeshed portions of the geometry, click “yes” to continue.

g. While Abaqus is solving the problem right click on the job submitted (arch_linear_static), and select “Monitor”

h. In the Monitor window check that there are no errors or warnings iii. If there are errors, investigate the cause(s) before resolving

iv. If there are warnings, determine if the warnings are relevant, some warnings can be safely ignored

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reh & Jenna Bell model tree rig

s”

menu bar click Uncheck the The locations Annotations ht click on the k on Viewport “Show comp s of viewport Options 15 e submitted a tÎViewport A pass option” items can be and successfu Annotations e specified on P ully complete Options n the correspo

Portland State Uni ed job (arch_l onding tab in iversity, Mechanic inear_static), the Viewpor al Engineering , and select t

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a. In the toolbox area click on the following icons i. “Plot Contours on Deformed Shape” ii. “Allow Multiple Plot States”

iii. “Plot Undeformed Shape”

28. In the toolbox area click on the “Common Plot Options” icon

a. Set the Deformation Scale Factor to 10 b. Click “OK”

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a. Set the probe to “Nodes”

b. In the viewport mouse over the element of interest

c. Note that Abaqus reports stress values from the integration points, which may differ slightly from the values determined by projecting values from surrounding integration points to the nodes

i. The minimum and maximum stress values contained in the legend are from the stresses projected to the nodes

d. Click on an element to store it in the “Selected Probe Values” portion of the dialogue box

30. The field output tool bar can be used to change the output displayed a. The middle drop down tab selects the field output of interest. b. The right drop down is used to select the variant or component.

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Abaqus/CAE

(ver. 6.10)

Material Nonlinearity Tutorial

Problem Description

A rectangular steel cantilevered beam has a downward load applied to the one end. The load is expected to

produce plastic deformation. An experimentally determined stress strain curve was supplied for the steel

material. We will investigate the magnitude and depth of plastic strain.

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Analysis Steps

1. Start Abaqus and choose to create a new model database

2. In the model tree double click on the “Parts” node (or right click on “parts” and select Create)

3. In the Create Part dialog box (shown above) name the part and a. Select “2D Planar”

b. Select “Deformable” c. Select “Shell”

d. Set approximate size = 200 e. Click “Continue…”

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a. Name the new material and give it a description

b. The stress strain data, shown below, was measured for the material used i. This data is based on the nominal (engineering) stress and strain

Nominal Stress (Pa) Nominal Strain

0.00E+00

2.00E+08

9.50E-04

2.40E+08

2.50E-02

2.80E+08

5.00E-02

3.40E+08

1.00E-01

3.80E+08

1.50E-01

4.00E+08

2.00E-01

ii. Abaqus expects the stress strain data to be entered as true stress and true plastic strain 1. In addition the modulus of elasticity must correspond to the slope defined by the

first point (the yield point)

iii. To convert the nominal stress to true stress, use the following equation

1. = (1 + )

iv. To convert the nominal strain to true strain, use the following equation

1. = (1 + )

v. To calculate the modulus of elasticity, divide the first nonzero true stress by the first nonzero true strain

vi. To convert the true strain to true plastic strain, use the following equation

1. = − 0.00E+00 1.00E+08 2.00E+08 3.00E+08 4.00E+08

-5.00E-16 2.50E-02 5.00E-02 7.50E-02 1.00E-01 1.25E-01 1.50E-01 1.75E-01 2.00E-01

Nominal Stress

(Pa)

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True Stress (Pa) Plastic Strain Elastic Modulus (Pa)

2.002E+08

0.000E+00

2.1083E+11

2.460E+08

2.374E-02

2.940E+08

4.784E-02

3.740E+08

9.436E-02

4.370E+08

1.388E-01

4.800E+08

1.814E-01

c. Click on the “Mechanical” tabÎElasticityÎElastic

i. Enter the calculated modulus of elasticity, and Poison’s ratio of 0.3 d. Click on the “Mechanical” tabÎPlasticityÎPlastic

i. Enter the calculated true stress and plastic strain

1. Note that you can simply copy your calculated values from Excel (or similar) and paste them into Abaqus

e. Click “OK”

6. Double click on the “Sections” node in the model tree

a. Name the section “PlaneStressProperties” and select “Solid” for the category and “Homogeneous” for the type

b. Click “Continue…”

c. Select the material created above (Steel) and set the thickness to 5. d. Click “OK”

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“Section Assignments”

a. Select the entire geometry in the viewport and press “Done” in the prompt area b. Select the section created above (PlaneStressProperties)

c. Verify “From section” is selected under “Thickness” d. Click “OK”

8. Expand the “Assembly” node in the model tree and then double click on “Instances” a. Select “Dependent” for the instance type

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9. Double click on the “Steps” node in the model tree

a. Name the step, set the procedure to “General”, and select “Static, General” b. On the Basic tab, give the step a description and change the time period to 2

i. For this analysis neglect the effects of geometric nonlinearities (Nlgeom = Off)

c. On the Incrementation tab,

i. Set the initial increment size to 0.05 ii. Set the maximum increment size to 0.2

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a. Name the boundary conditioned “Fixed” and select “Symmetry/Antisymmetry/Encastre” for the type

b. Select the left edge and click “Done”

c. Select “ENCASTRE” for the boundary condition and click “OK”

11. Double click on the “Amplitudes” node in the model tree

a. Name the amplitude “Triangular Loading” and select “Tabular” b. Enter the data points shown below

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load

12. Double click on the “Loads” node in the model tree

a. Name the load and select “Surface traction” as the type

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corner as the second point d. For the magnitude, enter 5e6

e. For the amplitude, select the amplitude created above (Triangular loading)

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Element Type” icon

a. Select the entire geometry

b. Select “Standard” for element type c. Select “Quadratic” for geometric order d. Select “Plane stress” for family

e. Note that the name of the element (S4R) and its description are given below the element controls f. Select “OK”

14. In the toolbox area click on the “Assign Mesh Controls” icon

a. Select the portion of the geometry associated with the boundary conditions and load b. Change the element shape to “Quad”

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15. In the toolbox area click on the “Seed Edges” icon

a. Select the left and right edges, click “Done” b. Select “By number”

c. Set “Bias” to “None”

d. Under “Sizing Controls” enter 8 elements, Click “OK”

16. In the toolbox area ensure the “Seed Edges” icon is still selected a. Select the top and bottom edges

b. Set “Method” to “By number” and “Bias” to “Single” c. Set the number of elements to 50

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to the left. If they don’t, click the “Select” button located to the right of “Flip Bias”

f. Select the top and bottom edges and select “Done”

g. The arrows should now point to the left h. Click the “OK” button

17. In the toolbox area click on the “Mesh Part” icon

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b. Give the job a description

19. In the model tree right click on the job just created and select “Submit” a. Ignore the message about unmeshed portions of the geometry

b. While Abaqus is solving the problem right click on the job submitted, and select “Monitor” c.

d. In the Monitor window check that there are no errors or warnings i. If there are errors, investigate the cause(s) before resolving

ii. If there are warnings, determine if the warnings are relevant, some warnings can be safely ignored

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21. In the menu bar click on ViewportÎViewport Annotations Options a. Uncheck the “Show compass option”

b. The locations of viewport items can be specified on the corresponding tab in the Viewport Annotations Options

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a. In the toolbox area click on the following icons i. “Plot Contours on Deformed Shape”

23. In the toolbox area click on the “Common Plot Options” icon a. Set the Deformation Scale Factor to 1

b. Click “OK”

24. Click on the arrows on the context bar to change the time step being displayed a. Click on the three squares to bring up the frame selector slider bar

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a. Select one of the plastic strain related outputs (PE or PEEQ) b. Click “OK”

Alternatively, you can select the output variable from the corresponding toolbar (shown below).

Hint: If you don’t see the toolbar, go to view Æ Toolbars and activate the “Field output” to display the

toolbar (a checkmark will appear next to it).

Note that PE displays individual plastic strain (similar to principal strain) components, while PEEQ variable

provides the equivalent plastic strain value (similar to vonMises equivalent stress).

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Spring 2011 01/21/11

ABAQUS Tutorial

3D Modeling

This exercise intends to demonstrate the steps you would follow in creating and analyzing a

simple solid model using ABAQUS CAE.

Introduction

A solid undergoes thermal expansion due to the application of heat along with deformation due to applied load.

Model Definition

Consider a thin aluminum cylinder of length 1 m and inner and outer radii 0.2 m & 0.21 m respectively. The cylinder is kept fixed at one end and at the other end a tensile load of 200 kPa is applied. The fixed end of the cylinder is at 273.15 K (the ambient temperature) and the free end at 274.15 K (all other sides are insulated). The cylinder expands due to the heat flow.

The various functions within ABAQUS are organized into modules and we are going to use these

modules to define the steps in our procedure.

1. >module load abaqus/6.9-2

2. >abaqus cae

3. Once you start ABAQUS CAE select Create Model Database to create a new model.

4. The default module that opens up is the Part Module.

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Part Module:

This module allows you to create the geometry required for the problem. To create a 3-D

geometry you first create a 2-D profile and then manipulate it to obtain the solid geometry.

1. From the Part Toolbox on the left of the viewport select Create Part.

2. You can name the part as cylinder or anything else you like. We are going to create a

deformable solid shape in the 3-D modeling space through extrusion so we do not

change the default selections.

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4. Click Create Circle Center and Perimeter on the drawing toolbox and enter 0, 0 as the

center point in field below the viewport and press Enter. Enter the perimeter point as

0.21, 0 and press Enter to complete the circle. Similarly make another circle with the

same center and the perimeter point as 0.2, 0. Press Esc to exit the circle definition and

then press Done.

5. Enter the extrusion depth as 1 and press OK.

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This finishes our work in the Part module. Select Module: Property from the toolbar above the

viewport.

Property Module:

In this module you define the material properties for your analysis and assign those properties

to the available parts.

1. Select Create Material from the Property Toolbox.

2. Enter material name as Aluminum. Click on the General tab and select Density from the

drop-down menu. Type in the mass density as 2700. Click on the Mechanical tab and

select Elasticity>Elastic from the drop-down menu. Enter the Young’s Modulus as 70E9

and the Poisson’s Ratio as 0.33. Click on the Mechanical tab and select Expansion. Edit

the reference temperature to 273.15 and the expansion coefficient to 23e-6. Click on

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the Thermal tab and select Conductivity. Enter the thermal conductivity as 160. Click on

the Thermal tab and select Specific Heat. Enter the value as 900 and click OK.

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3. Select Create Section from the property toolbox. Name the section as you like. We need

a solid homogeneous section for our problem. Click Continue. Select the material as

Aluminum and click OK.

4. Click Assign Section on the property toolbox and select the part from the viewport. Click

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Our work in the Property module is done and we select the Assembly Module from the toolbar

above the viewport.

Assembly Module:

This module allows you to assemble together parts that you have created. Even if you have a

single part you need to include it in your assembly.

1. Select Instance Part from the Assembly Toolbox.

2. Select the part you have created from the parts list and then select Instance type:

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Select Module: Step from the toolbar above.

Step Module:

This module allows you to select the kind of analysis you want to perform on your model and

define the parameters associated with it. You can also select which variables you want to

included in the output files in this modules. You apply loads over a step. To apply a sequence of

loads create several steps and define the loads for each of them.

1. Select Create Step from the Step Toolbox.

2. Name the step as you want and select Coupled temp-displacement as the procedure.

Click Continue.

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3. The edit step dialog box lets you choose the solution technique, the solver type and

define the time stepping strategy.

4. Under Basic change the Response to Steady-state and click OK.

The Interaction Module allows you to set up interactions (contact, film), constraints,

connectors, fasteners and wire feature between parts. Our problem does not involve any of

these features but it will be a good idea to explore this module on your own at a later time.

Select Module: Load from the toolbar above.

Load Module:

The Load Module is where you define the loads and boundary conditions for your model for a

particular step (indicated in the toolbar above). You can even define loads and boundary

conditions as fields like electric potential, acoustic pressure, etc.

1. Select Create Load from the Load Toolbox. Select Surface Traction and click Continue.

Select the top face of the cylinder (z=1) (it gets highlighted in red) and click Done.

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2. Change the Traction type to General. Click on the Edit tab under Direction in the dialog

box. Enter the starting point of the direction vector as (0, 0, 0) and the end point as (0,0,

1). Enter the Magnitude as 2e5 and click OK.

3. Select Create Boundary Condition from the Load Toolbox. Select Symmetry /

Antisymmetry / Encastre and click Continue. Select the bottom face (z=0) of the

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4. Again select Create Boundary Condition from the Load Toolbox. Switch Category to

Other and select Temperature and click Continue. Select the bottom face of the cylinder

and press Done. Enter the magnitude as 273.15 and click OK. Similarly put the top face

at 274.15.

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Now that we have defined the loads and the boundary conditions we move on to mesh the

geometry. Select Module: Mesh from the toolbar above the viewport.

Mesh Module:

The mesh model controls how you mesh your model – the type of element, their size etc.

1. Select Seed Part Instance from the mesh toolbox. Enter the approximate global size as

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3. Select Assign Element Type from the mesh toolbox. Under Family select Coupled

Temperature-Displacement and switch Geometric Order to Quadratic. Click OK.

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When finished select Module: Job from the toolbar above.

Job Module:

This module allows you to submit your model for analysis.

1. Select Create Job from the Job Toolbox. Name the job as you like. Select your model

and click Continue.

2. You can add a description to the job, allocate memory, allot multiple processors and

select precision. Use the default values and click OK.

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4. If you are running the job for the first time it is advisable to run Data Check to check the

input file for errors. Click OK to overwrite the job files.

5. Once the data check is completed Submit the job for analysis. Click OK to overwrite the

job files. You can click Monitor to observe the progress of the solution process. You can

see the errors, warnings, data and message file.

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6. Once the job is completed click on the Results tab on the job manager. This opens the

Visualization Module for postprocessing.

Visualization Module:

This model allows you to look at your model after deformation. You can also plot values of

stress, displacement, reaction forces, etc. as contours on your model surface or as vectors

or tensors.

1. Select Plot Deformed Shape from the Visualization toolbox.

2. Select Plot Contours on Deformed Shape to plot stress contours on the model

surface.

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3. You can see the location of the maximum & minimum stresses by selecting Contour

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4. Select Results>Field Output from the main menu. This opens a dialog box that

allows you to select the variable you want to plot in the viewport.

5. Select U (Spatial Displacement at nodes)>Magnitude>OK to plot the displacement

contours on the model.

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6. To plot displacement vectors click on Plot Symbols on Deformed Shape on the

toolbox.

7. You can now animate this plot by selecting Animate Harmonic.

Mouse Gestures:

Ctrl+Alt+Left Click (MB1): Rotate View

Ctrl+Alt+Middle Click (MB2): Pan View

Ctrl+Alt+Right Click (MB3): Magnify View

Use Shift key to select multiple objects.

Note on System of Units:

ABAQUS has no built-in system of units. Specify all unit data in consistent units. Some common

systems of consistent units:

SI: m, N, kg, s, Pa, J, kg/m

3

SI (mm): mm, N, tonne (1000 kg), s, MPa, mJ, tonne/mm

3

US Unit (ft): ft, lbf, slug, s, lbf/ft

2

, ft lbf, slug/ft

3

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ME 455/555 Intro to Finite Element Analysis Winter ‘09 Abaqus/CAE truss tutorial

Abaqus/CAE Truss Tutorial

(Revised January 21, 2009)

Problem Description:

Solve for displacements of the free node and the reaction forces of the truss structure shown in the

figure. This is the sample problem from the lecture note example.

Material is Steel with E = 210 GPa and

υ

=0.25.

1000 mm2

1250 mm2

750 mm

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Analysis Steps

1. Start Abaqus and choose to create a new model database 2. In the model tree double click on the “Parts” node (or right click on “parts” and select Create) 3. In the Create Part dialog box (shown above) name the part and a. Select “2D Planar” b. Select “Deformable” c. Select “Wire” d. Set approximate size = 1 e. Click “Continue…” 4. Create the geometry shown below (not discussed here)

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©2009 Hormoz Zareh & Jayson Martinez 3 Portland State University, Mechanical Engineering 5. Double click on the “Materials” node in the model tree a. Name the new material and give it a description b. Click on the “Mechanical” tabÎElasticityÎElastic c. Define Young’s Modulus and Poisson’s Ratio (use base SI units) i. WARNING: There are no predefined system of units within Abaqus, so the user is responsible for ensuring that the correct values are specified d. Click “OK”

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6. Double click on the “Sections” node in the model tree a. Name the section “HorizontalBar” and select “Beam” for both the category and “Truss” for the type b. Click “Continue…” c. Select the material created above (Steel) d. Set cross‐sectional area = 0.001 (base SI units, m2) e. Click “OK” f. Repeat for the “AngledBar” i. Cross‐sectional area=0.00125

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©2009 Hormoz Zareh & Jayson Martinez 5 Portland State University, Mechanical Engineering 7. Expand the “Parts” node in the model tree, expand the node of the part just created, and double click on “Section Assignments” a. Select the horizontal portion of the geometry in the viewport b. Click “Done” c. Select the “HorizontalBar” section created above d. Click “OK” e. Repeat for the angled portion of the geoemetry 8. Expand the “Assembly” node in the model tree and then double click on “Instances” a. Select “Dependent” for the instance type b. Click “OK”

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©2009 Hormoz Zareh & Jayson Martinez 6 Portland State University, Mechanical Engineering 9. Double click on the “Steps” node in the model tree a. Name the step, set the procedure to “General”, and select “Static, General” b. Click “Continue…” c. Give the step a description d. Click “OK”

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©2009 Hormoz Zareh & Jayson Martinez 7 Portland State University, Mechanical Engineering 10. Expand the Field Output Requests node in the model tree, and then double click on F‐Output‐1 (F‐ Output‐1 was automatically generated when creating the step) a. Uncheck the variables “Strains” and “Contact” b. Click “OK” 11. Expand the History Output Requests node in the model tree, and then right click on H‐Output‐1 (H‐ Output‐1 was automatically generated when creating the step) and select Delete

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©2009 Hormoz Zareh & Jayson Martinez 8 Portland State University, Mechanical Engineering 12. Double click on the “BCs” node in the model tree a. Name the boundary conditioned “Pinned” and select “Displacement/Rotation” for the type b. Click “Continue…” c. Select the endpoints on the left (“shift” select ) and press “Done” in the prompt area d. Check the U1 and U2 displacements and set them to 0 e. Click “OK”

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©2009 Hormoz Zareh & Jayson Martinez 9 Portland State University, Mechanical Engineering 13. Double click on the “Loads” node in the model tree a. Name the load “PointLoad” and select “Concentrated force” as the type b. Click “Continue…” c. Select the vertex on the right and press “Done” in the prompt area d. Specify CF2 = ‐1000 e. Click “OK”

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©2009 Hormoz Zareh & Jayson Martinez 10 Portland State University, Mechanical Engineering 14. In the model tree double click on “Mesh” for the Truss part, and in the toolbox area click on the “Assign Element Type” icon a. Select “Standard” for element type b. Select “Linear” for geometric order c. Select “Truss” for family d. Note that the name of the element (B21) and its description are given below the element controls e. Click “OK” 15. In the toolbox area click on the “Seed Edge: By Number” icon (hold down icon to bring up the other options) a. Select the entire geometry and click “Done” in the prompt area

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©2009 Hormoz Zareh & Jayson Martinez 11 Portland State University, Mechanical Engineering b. Define the number of elements along the edges as 1 and click “Enter” in the prompt region, then “Done” in response to the next prompt. c. 16. In the toolbox area click on the “Mesh Part” icon a. Click “Yes” in the prompt area 17. In the menu bar select ViewÎPart Display Options a. On the Mesh tab check “Show node labels” and “Show element labels” b. Click “OK”

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©2009 Hormoz Zareh & Jayson Martinez 12 Portland State University, Mechanical Engineering 18. In the model tree double click on the “Job” node a. Name the job “Truss” b. Click “Continue…” c. Give the job a description d. Click “OK”

19. In the model tree right click on the job just created (Truss) and select “Submit” a. While Abaqus is solving the problem right click on the job submitted (Truss), and select “Monitor”

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©2009 Hormoz Zareh & Jayson Martinez 13 Portland State University, Mechanical Engineering b. In the Monitor window check that there are no errors or warnings i. If there are errors, investigate the cause(s) before resolving ii. If there are warnings, determine if the warnings are relevant, some warnings can be safely ignored 20. In the model tree right click on the submitted and successfully completed job (Truss), and select “Results”

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©2009 Hormoz Zareh & Jayson Martinez 14 Portland State University, Mechanical Engineering 21. In the menu bar click on ViewportÎViewport Annotations Options a. Uncheck the “Show compass option” b. The locations of viewport items can be specified on the corresponding tab in the Viewport Annotations Options c. Click “OK” 22. Display the deformed contour of the (Von) Mises stress overlaid with the undeformed geometry a. In the toolbox area click on the following icons i. “Plot Contours on Deformed Shape” ii. “Allow Multiple Plot States” iii. “Plot Undeformed Shape”

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©2009 Hormoz Zareh & Jayson Martinez 15 Portland State University, Mechanical Engineering 23. In the toolbox area click on the “Common Plot Options” icon a. Note that the Deformation Scale Factor can be set on the “Basic” tab b. On the “Labels” tab check “Show element labels”, “Show node labels”, and “Show node symbols” c. Click “OK”

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©2009 Hormoz Zareh & Jayson Martinez 17 Portland State University, Mechanical Engineering 24. To determine the stress values, from the menu bar click ToolsÎQuery Æ Probe Values, and click OK. a. Check the boxes labeled “Nodes” and “S, Mises” b. In the viewport mouse over the element of interest c. Note that Abaqus reports stress values from the integration points, which may differ slightly from the values determined by projecting values from the surrounding integration points to the nodes i. The minimum and maximum stress values contained in the legend are from the stresses projected to the nodes d. Click on an element to store it in the “Selected Probe Values” portion of the dialogue box e. Click “Cancel” 25. To change the output being displayed, in the menu bar click on ResultsÎField Output a. Select “Spatial displacement at nodes” i. Component = U2 b. Click “OK”

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26. To create a text file containing the stresses, vertical displacements, and reaction forces (including the total), in the menu bar click on ReportÎField Output a. For the output variable select (Von) Mises b. On the Setup tab specify the name and the location for the text file c. Uncheck the “Column totals” option d. Click “Apply”

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e. Back on the Variable tab change the position to “Unique Nodal” f. Uncheck the stress variable, and select the U2 spatial displacement g. Click “Apply” h. On the Variable tab, uncheck Spatial displacement and select the RF2 reaction force i. On the Setup tab, check the “Column totals” option j. Click “OK”

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27. Open the .rpt file with any text editor

a. One thing to check is that the total downward reaction force is equal to the applied load (1,000 N)

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1

Abaqus/CAE

(ver. 6.8)

Vibrations Tutorial

Problem Description

The two dimensional bridge structure, which consists of steel T‐sections, is simply supported at its lower corners. Determine the first 10 eigenvalues and natural frequencies.

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2

Analysis Steps

1. Start Abaqus and choose to create a new model database 2. In the model tree double click on the “Parts” node (or right click on “parts” and select Create) 3. In the Create Part dialog box (shown above) name the part and a. Select “2D Planar” b. Select “Deformable” c. Select “Wire” d. Set approximate size = 20 e. Click “Continue…” 4. Create the geometry shown below (not discussed here)

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3 5. Double click on the “Materials” node in the model tree a. Name the new material and give it a description b. Click on the “Mechanical” tabÎElasticityÎElastic c. Define Young’s Modulus and Poisson’s Ratio (use SI units) i. WARNING: There are no predefined system of units within Abaqus, so the user is responsible for ensuring that the correct values are specified d. Click on the “General” tabÎDensity e. Density = 7800 f. Click “OK”

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4 6. Double click on the “Profiles” node in the model tree a. Name the profile and select “T” for the shape i. Note that the “T” shape is one of several predefined cross‐sections b. C lick “Continue…” c. Enter the values for the profile shown below d. Click “OK” 7. Double click on the “Sections” node in the model tree a. Name the section “BeamProperties” and select “Beam” for both the category and the type b. Click “Continue…” c. Leave the section integration set to “During Analysis” d. Select the profile created above (T‐Section) e. Select the material created above (Steel) f. Click “OK”

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5 8. Expand the “Parts” node in the model tree, expand the node of the part just created, and double click on “Section Assignments” a. Select the entire geometry in the viewport b. Select the section created above (BeamProperties) c. Click “OK” 9. Expand the “Assembly” node in the model tree and then double click on “Instances” a. Select “Dependent” for the instance type b. Click “OK”

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6 10. Double click on the “Steps” node in the model tree a. Name the step, set the procedure to “Linear perturbation”, and select “Frequency” b. Click “Continue…” c. Give the step a description d. Select the radio button “Value” under “Number of eigenvalues requested “ and enter 10 e. Click “OK” 11. Double click on the “BCs” node in the model tree a. Name the boundary conditioned “Pinned” and select “Displacement/Rotation” for the type b. Click “Continue…” c. Select the lower‐left vertex of the geometry and press “Done” in the prompt area d. Check the U1 and U2 displacements and set them to 0 e. Click “OK” f. Repeat for the lower‐right vertex, but model a roller restraint (only U2 fixed) instead

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7 12. In the model tree double click on “Mesh” for the Bridge part, and in the toolbox area click on the “Assign Element Type” icon a. Select “Standard” for element type b. Select “Linear” for geometric order c. Select “Beam” for family d. Note that the name of the element (B21) and its description are given below the element controls e. Click “OK” 13. In the toolbox area click on the “Seed Edge: By Number” icon (hold down icon to bring up the other options) a. Select the entire geometry and click “Done” in the prompt area b. Define the number of elements along the edges as 5 14. In the toolbox area click on the “Mesh Part” icon a. Click “Yes” in the prompt area

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8 15. In the menu bar select ViewÎPart Display Options a. Check the Render beam profiles option b. Click “OK” 16. Change the Module to “Property” a. Click on the “Assign Beam Orientation” icon b. Select the entire geometry from the viewport c. Click “Done” in the prompt area d. Accept the default value of the approximate n1 direction 17. Note that the preview shows that the beam cross sections are not all orientated as desired (see Problem Description)

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9 18. In the toolbox area click on the “Assign Beam/Truss Tangent” icon a. Click on the sections of the geometry that are off by 180 degrees 19. In the model tree double click on the “Job” node a. Name the job “Bridge” b. Click “Continue…” c. Give the job a description d. Click “OK”

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10 20. In the model tree right click on the job just created (Bridge) and select “Submit” a. While Abaqus is solving the problem right click on the job submitted (Bridge), and select “Monitor”

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11 b. In the Monitor window check that there are no errors or warnings i. If there are errors, investigate the cause(s) before resolving ii. If there are warnings, determine if the warnings are relevant, some warnings can be safely ignored 21. In the model tree right click on the submitted and successfully completed job (Bridge), and select “Results”

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12 22. In the menu bar click on ViewportÎViewport Annotations Options a. Uncheck the “Show compass option” b. The locations of viewport items can be specified on the corresponding tab in the Viewport Annotations Options c. Click “OK” 23. Display the deformed contour overlaid with the undeformed geometry a. In the toolbox area click on the following icons i. “Plot Contours on Deformed Shape” ii. “Allow Multiple Plot States” iii. “Plot Undeformed Shape”

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13 24. In the toolbox area click on the “Common Plot Options” icon a. Note that the Deformation Scale Factor can be set on the “Basic” tab b. On the “Labels” tab check the show node symbols icon c. Click “OK”

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14 25. In the menu bar click on Results ÎStep/Frame a. Change the mode by double clicking in the “Frame” portion of the window b. Observe the eigenvalues and frequencies c. Click “OK” 26. In the toolbox area click on “Animation Options” a. Change the Mode to “Swing” b. Click “OK” c. Animate by clicking on “Animate: Scale Factor” icon in the toolbox area d. Stop the animation by clicking on the icon again 27. Click on the “Next” arrow on the context bar to change the mode

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15 28. Expand the “Bridge.odb” node in the result tree, expand the “History Output” node, and right‐click on “Eigenfrequency: …” a. Select “Save As…” b. Name = Frequencies c. Repeat for “Eigenvalue” d. Observe the XYData nodes in the result tree 29. In the menu bar click on ReportÎXY… a. Select from = All XY data b. Highlight “Eigenvalues” c. Click on the “Setup” tab d. Click “Select…” and specify the desired name and location of the report e. Click “Apply” f. Click on the “XY Data” tab g. Highlight “Frequencies” h. Click “OK”

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16

30. Open the report (.rpt file) with any text editor

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Abaqus/CAE Vibrations Tutorial

Problem Description

The table frame, made of steel box sections, is fixed at the end of each leg. Determine the first 10 eigenvalues and natural frequencies. WARNING: There is no predefined system of units within Abaqus, so the user is responsible for ensuring that the correct values are specified. Here we use SI units

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Analysis Steps

1. Start Abaqus and choose to create a new model database 2. In the model tree double click on the “Parts” node (or right click on “parts” and select Create) 3. In the Create Part dialog box (shown above) name the part and a. Select “3D” b. Select “Deformable” c. Select “Wire” d. Set approximate size = 5 (Not important, determines size of grid to display) e. Click “Continue…” f. Create the sketch shown below

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©2009 Jayson Martinez & Hormoz Zareh 3 Portland State University, Mechanical Engineering 4. In the toolbox area click on the “Create Datum Plane: Offset From Principle Plane” icon a. Select the “XY Plane” and enter a value of 1 for the offset 5. In the toolbox area click on the “Create Wire: Planar” icon a. Click on the outline of the datum plane created in the previous step b. Select any one of the lines to appear vertical and on the right c. In the toolbox area click on the “Project Edges” icon d. Select all of the lines in the viewport and click “Done” 6. In the toolbox area click on the “Create Datum Plane: 3 points” icon (click on the small black triangle in the bottom‐right corner of the icon to get all of the datum plane options) a. Select 3 points on the top of the geometry

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©2009 Jayson Martinez & Hormoz Zareh 4 Portland State University, Mechanical Engineering 7. In the toolbox area click on the “Create Wire: Planar” icon a. Click on the outline of the datum plane created in the previous step b. Select any one of the lines to appear vertical and on the right c. Sketch two lines to connect finish the wireframe of the table d. Click on “Done” 8. Double click on the “Materials” node in the model tree a. Name the new material and give it a description b. Click on the “Mechanical” tabÎElasticityÎElastic c. Define Young’s Modulus (210e9) and Poisson’s Ratio (0.25)

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©2009 Jayson Martinez & Hormoz Zareh 5 Portland State University, Mechanical Engineering d. Click on the “General” tabÎDensity e. Density = 7800 f. Click “OK” 9. Double click on the “Profiles” node in the model tree a. Name the profile and select “Box” for the shape b. Click “Continue…” c. Enter the values for the profile shown below d. Click “OK” 10. Double click on the “Sections” node in the model tree a. Name the section “BeamProperties” and select “Beam” for both the category and the type b. Click “Continue…” c. Leave the section integration set to “During Analysis” d. Select the profile created above (BoxProfile) e. Select the material created above (Steel) f. Click “OK”

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©2009 Jayson Martinez & Hormoz Zareh 6 Portland State University, Mechanical Engineering 11. Expand the “Parts” node in the model tree, expand the node of the part just created, and double click on “Section Assignments” a. Select the entire geometry in the viewport b. Select the section created above (BeamProperties) c. Click “OK” 12. Expand the “Assembly” node in the model tree and then double click on “Instances” a. Select “Dependent” for the instance type b. Click “OK”

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©2009 Jayson Martinez & Hormoz Zareh 7 Portland State University, Mechanical Engineering 13. Double click on the “Steps” node in the model tree a. Name the step, set the procedure to “Linear perturbation”, and select “Frequency” b. Click “Continue…” c. Give the step a description d. Select “Lanczos” for the Eigensolver e. Select the radio button “Value” under “Number of eigenvalues requested “ and enter 10 f. Click “OK” 14. Double click on the “BCs” node in the model tree a. Name the boundary conditioned “Fixed” and select “Symmetry/Antisymmetry/Encastre” for the type b. Click “Continue…” c. Select the end of each leg and press “Done” in the prompt area d. Select “ENCASTRE” for the boundary condition (“ENCASTRE” means completely fixed/clamped) e. Click “OK”

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©2009 Jayson Martinez & Hormoz Zareh 8 Portland State University, Mechanical Engineering 15. In the model tree double click on “Mesh” for the Table frame part, and in the toolbox area click on the “Assign Element Type” icon a. Select “Standard” for element type b. Select “Linear” for geometric order c. Select “Beam” for family d. Click “OK” 16. In the toolbox area click on the “Seed Part” icon a. Set the approximate global size to 0.1 17. In the toolbox area click on the “Mesh Part” icon a. Click “Yes” in the prompt area

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©2009 Jayson Martinez & Hormoz Zareh 9 Portland State University, Mechanical Engineering 18. In the menu bar select ViewÎPart Display Options a. Check the Render beam profiles option b. Click “OK” 19. Change the Module to “Property” a. Click on the “Assign Beam Orientation” icon b. Select the portions of the geometry that are perpendicular to the Z axis c. Click “Done” in the prompt area d. Accept the default value of the approximate n1 direction (0,0,‐1) e. Click “OK” in the prompt area f. Select the portions of the geometry that are parallel to the Z axis

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©2009 Jayson Martinez & Hormoz Zareh 10 Portland State University, Mechanical Engineering g. Click “Done” in the prompt area h. Enter a vector that is perpendicular to the Z axis for the approximate n1 direction (i.e. 0,1,0) i. Click “OK” followed by “Done” in the prompt area 20. In the model tree double click on the “Job” node j. Name the job “TableFrame” k. Click “Continue…” l. Give the job a description m. Click “OK”

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©2009 Jayson Martinez & Hormoz Zareh 11 Portland State University, Mechanical Engineering 21. In the model tree right click on the job just created (TableFrame) and select “Submit” n. While Abaqus is solving the problem right click on the job submitted (TableFrame), and select “Monitor” o. In the Monitor window check that there are no errors or warnings i. If there are errors, investigate the cause(s) before resolving ii. If there are warnings, determine if the warnings are relevant, some warnings can be safely ignored 22. In the model tree right click on the submitted and successfully completed job (TableFrame), and select “Results”

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©2009 Jayson Martinez & Hormoz Zareh 12 Portland State University, Mechanical Engineering 23. In the menu bar click on ViewportÎViewport Annotations Options p. The locations of viewport items can be specified on the corresponding tab in the Viewport Annotations Options q. Click “OK” 24. Display the deformed contour overlaid with the undeformed geometry r. In the toolbox area click on the following icons iii. “Plot Contours on Deformed Shape” iv. “Allow Multiple Plot States” v. “Plot Undeformed Shape” 25. In the menu bar click on Results ÎStep/Frame s. Change the mode by double clicking in the “Frame” portion of the window t. Observe the eigenvalues and frequencies u. Leave the dialogue box open to be able to switch the mode shapes while animating

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©2009 Jayson Martinez & Hormoz Zareh 13 Portland State University, Mechanical Engineering 26. In the toolbox area click on “Animation Options” v. Change the Mode to “Swing” w. Click “OK” x. Animate by clicking on “Animate: Scale Factor” icon in the toolbox area 27. Click on a different Frame in the “Step/Frame” dialogue box to change the mode 28. Expand the “TableFrame.odb” node in the result tree, expand the “History Output” node, and right‐click on “Eigenfrequency: …” y. Select “Save As…” z. Name = Frequencies

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©2009 Jayson Martinez & Hormoz Zareh 14 Portland State University, Mechanical Engineering aa. Repeat for “Eigenvalue” bb. Observe the XYData nodes in the result tree 29. In the menu bar click on ReportÎXY… cc. Select from = All XY data dd. Highlight “Eigenvalues” ee. Click on the “Setup” tab ff. Click “Select…” and specify the desired name and location of the report gg. Click “Apply” hh. Click on the “XY Data” tab ii. Highlight “Frequencies” jj. Click “OK”

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©2009 Jayson Martinez & Hormoz Zareh 15 Portland State University, Mechanical Engineering 30. Open the report (.rpt file) with any text editor Note: Eigen values that are identical indicate similar vibration modes, activated in different planes.

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Abaqus/CAE Axisymmetric Tutorial

Problem Description

A round bar with varying diameter has a total load of 1000 N applied to its top face. The bottom of the bar is completely fixed. Determine stress and displacement values in the bar resulting from the load.