AE4131 ABAQUS Lecture Part IV

1. AE4131ABAQUS LecturePart IV Patrick Roberts gt0398b@prism.gatech.edu x5-2773 Weber 201

2. 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.

3. 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.

4. Adjusting extrusion depth Example: Let’s 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.

5. 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.

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

7. 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

8. Adjust by dimensioning • Click on this button then click the vertical lines at each end of the beam. • As soon as you click on the second vertical line a dimension will appear. Place this above the beam.

9. 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.

10. Adjust by dimensioning Your sketch will look like

11. Adjust by dimensioning When you click Done the 3D view will redraw itself to look like

12. 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.

13. Adding extrusions • From the main menu bar, select Shape, Solid, Extrude. • Select a face to define the sketching plane. Select the face at the free end of the beam. • 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. • Draw a rectangle 5mm high and 10mm wide which is centered on this face. • 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 it’s in the direction of the new extrusion.

14. 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.

15. 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 model’s construction.

16. Creating Axisymmetric models • If a geometry is symmetric about an axis you should use revolve rather than extrude. For example let’s create a cylinder 50 mm long with a radius of 5mm • Click on Part, Create. In the dialog box we indicate that it’s 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.

17. Creating Axisymmetric models • Click Done • In the Edit Revolution enter 360 in the Angle field. When you click ok you will see the following.

18. 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.

19. 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.

20. 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.

21. 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 1381:1385.

22. Viewing results along a path • To plot these results go to Tools, XY Data, Create. • 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). • Click Plot to generate an X–Y plot of U along the path.

23. Viewing results along a path