AE4131 ABAQUS Lecture Part IV

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AE4131ABAQUS LecturePart IV

• Patrick Roberts
• gt0398b_at_prism.gatech.edu
• x5-2773
• Weber 201

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Starting ABAQUS CAE
You can start ABAQUS CAE from the start menu or
with a command line by typing abaqus cae TIP
You should start ABAQUS CAE via command line from
the directory you want your results files to end
up.
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Adjusting geometries

• There will be many times where you will need to
  change the geometry of a model after you have
  created the part(s).
• There are two methods to adjust goemetries
• Change extrusion depth
• Change the labeled dimension on a part.

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Adjusting extrusion depth

• Example Lets look at a 3D beam that has
  dimensions of 200mm length, 20 mm height, and 30
  mm width. The width dimension was extruded. We
  want to change this to an extrusion of 10 mm.

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Adjusting extrusion depth

• Click Feature, Edit. Click on the beam to
  indicate that is the geometry you want to change.
• A dialog will ask for the new extrusion depth.
  Make sure that Regeneration on OK is checked.

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Adjust by dimensioning

• You can adjust a parts geometry by adjusting a
  dimension. Lets use the beam example to show
  how this can be done. Lets say the beam must be
  shortened to 100 mm. Because this is not an
  extruded dimension we must adjust this using
  dimensions.

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Adjust by dimensioning

• Click Feature, Edit. Click on the beam to
  indicate that is the geometry you want to change.
• A dialog will ask for the new extrusion depth.
  Make sure that Regeneration on OK is checked.
  Click on Edit Section Sketch. This will put you
  back in the sketcher.
• The length of the beam needs a dimension. Look
  on the button palette on the left for a symbol
  that looks like
• This button is called Create Dimension Horizontal

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Adjust by dimensioning

1. Click on this button then click the vertical
   lines at each end of the beam.
2. As soon as you click on the second vertical line
   a dimension will appear. Place this above the
   beam.

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Adjust by dimensioning

• Now that we have a dimension we can adjust the
  length of the beam by changing the number in the
  dimension.
• 6. Click on the button called Edit Dimension
  Value
• 7. Click on the dimension number that will be
  changed then hold down the Shift key and click on
  the end points of one of the vertical lines.
• 8. When you are done click the middle mouse
  button (the wheel). It will prompt you for the
  new dimension. Enter 100 then OK.

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Adjust by dimensioning

• Your sketch will look like

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Adjust by dimensioning

• When you click Done the 3D view will redraw
  itself to look like

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Adding extrusions

• There may be times where you would like to add an
  extrusion to an existing part. Sort of like
  growing an additional geometry on an existing
  geometry.
• For this example we want to add a small
  cantilever extension along the current
  longitudinal axis of the existing beam. The
  dimensions of this extrusion is 50mm long, 5mm
  high and 10mm wide.

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Adding extrusions

1. From the main menu bar, select Shape, Solid,
   Extrude.
2. Select a face to define the sketching plane.
   Select the face at the free end of the beam.
3. Select an edge that will appear vertical and on
   the right side of the sketch. Once this has been
   selected you will be placed in the sketcher.
4. Draw a rectangle 5mm high and 10mm wide which is
   centered on this face.
5. When this is Done you will be placed in 3D view.
   Take a look at the free end of the beam and you
   will see a red arrow. Make sure its in the
   direction of the new extrusion.

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Adding extrusions

• 6. In the dialog box make sure Type is Blind and
  Depth is 50. When you click ok the beam now
  looks like.

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Some notes about adjusting models

• Depending on where you are in the assembly of
  your model you may have to go back and repeat
  some of the steps such as meshing and boundary
  conditions.
• After you have adjusted a model you should always
  verify each step in a models construction.

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Creating Axisymmetric models

• If a geometry is symmetric about an axis you
  should use revolve rather than extrude. For
  example lets create a cylinder 50 mm long with a
  radius of 5mm
• Click on Part, Create. In the dialog box we
  indicate that its a 3D, deformable part but in
  Type we pick Revolution. You will now be placed
  in the sketcher.
• Use of the major axis in sketcher is very
  important when drawing axisymetric parts. Draw a
  rectangle that is 50 high and 5 from the major
  vertical axis of the sketch area as seen below.

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Creating Axisymmetric models

1. Click Done
2. In the Edit Revolution enter 360 in the Angle
   field. When you click ok you will see the
   following.

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Viewing results along a path

• To obtain more insight into the stresses and
  strains of a loaded structure we may want to view
  results along a line rather than a point.
• To demonstrate this we will use the example of
  the 3D cantilever beam. In this example we want
  to see the stresses along a centered vertical
  line just inside the structure at the root.

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Viewing results along a path

• In using the Display Group functionality spoken
  of in a previous lecture we will display just
  those elements at the root end.

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Viewing results along a path

• Now we would like to tell ABAQUS we want to view
  the results along the vertical centerline of the
  displayed elements. We do this by defining a
  path.
• There are two ways to define a path 1) using node
  numbers and 2) by specifying points.
• If you use nodes the nodes will displace when the
  structure is loaded.

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Viewing results along a path

• In our example we will use nodes.
• Turn on node labels.
• In our example nodes 1381 through 1385 define our
  path.
• Click on Tools, Path, Create. Will call this
  Monitor. Make sure Node list is indicated.
• In the Edit Node List Path dialog we can enter
  the node labels under Node Labels as 13811385.

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Viewing results along a path

1. To plot these results go to Tools, XY Data,
   Create.
2. In the Create XY Data dialog box that appears,
   select Path and click Continue. The XY Data
   from Path dialog box appears with the path that
   you created visible in the list of available
   paths. Accept the default selections in the X
   Values portion of the dialog box. The result
   that will be plotted is displayed in the Y Values
   portion of the dialog box. In this case U is the
   field output variable that was selected last
   (when you generated the symbol plot).
3. Click Plot to generate an XY plot of U along the
   path.

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Viewing results along a path