Demonstration 8b Visualizing Results

Demonstration 8b

Visualizing Results

© Dassault Systèmes, 2020 Introduction to Abaqus

Introduction

The Visualization module in Abaqus/CAE provides a graphical display of Abaqus finite

element models and results. It obtains the model and result information from the output

database (.odb) file. This demonstration presents some of the capabilities of this module,

including:

Using the Results Tree

Color coding based on material assignment

Contouring results

Displaying a subset of a model

Opening multiple output database files

X–Y plotting

Overlaying results

Animation of results

You will need output database files manifold.odb and

indentfoam_std_visco_2.odb (created prior to Demonstration 1). Start a new

Abaqus/CAE session, and select Open Database in the Start Session dialog box.

Choose manifold.odb.

Color Coding the Elements Based on Materials

Color the elements with different colors. In this exercise the color selection is based on

material assignments. Use the Results Tree to identify which regions of the model are

associated with a given material.

1. In the Results Tree, expand the Materials container underneath the output

database file named manifold.odb. Select each material in turn to highlight the

elements associated with that material in the viewport.

2. In the toolbar, select Materials from the pull-down list .

3. Click the Color Code icon .


D8b.2

4. Select the material CASTFE (associated with the manifold). Double-click the

color selection and select the dark blue color ( ) in the Select Color

dialog box.

5. Select the material STEEL (associated with the bolts). Select the yellow color

( ).

6. Select the material ALUM (associated with the head). Select the red color ( ).

7. Click Apply in the Color Code dialog box.

8. Restore the default colors for the materials (in the dialog box, select the cells in

the column labeled Color; from the bottom of the dialog box, select Color

Mapping→Auto-Color Selected and click Apply).

Contouring Results and View Cuts

1. Contour the Mises stress on the deformed model shape.

2. Review the various options available for contour plotting by clicking the Contour

Options icon. Set the maximum contour value to 100.

3. Choose the Plot Contours on Undeformed Shape icon to plot the contours on

the undeformed shape of the model.

Note that any element for which this output is not available is displayed in white.

4. Use view cuts to plot contours on an arbitrary interior region of the model, as

shown in Figure D8b–1.

Figure D8b–1 Multi-plane view cut of the manifold

(X-plane position = 90; Y-plane position=35)


D8b.3

5. Suppress the view cuts.

6. Use the field output toolbar to change the primary contour variable to TEMP.

Contour the nodal temperatures at the end of the second step, as shown in Figure

D8b–2. As before, any element for which this output is not available is displayed

in white.

Figure D8b–2 Temperature distribution at end of second step

Displaying a Subset of a Model

By default, Abaqus/CAE displays the entire model; however, you can define a display

group to display a subset of a model. This group may contain any combination of nodes,

elements, and surfaces. To create or edit a display group, you perform Boolean operations

between selected model components and the contents of the current viewport.

To create a display group based on material assignment:

1. In the Materials container of the Results Tree, click mouse button 3 on CASTFE.

In the menu that appears, select Replace.

Alternative 1: click the Replace tool in the toolbar, select Materials from the

pull-down list in the prompt area, and click anywhere on the manifold.

Alternative 2: double-click the Display Groups container of the Results Tree or

click the Display Groups icon in the toolbar to perform the replace operation

using the Create Display Group dialog box.

2. To invert the display, click the Invert Display tool in the toolbar.

3. To restore the visibility of the entire model, expand the Display Groups

container of the Results Tree and double-click All.

Alternative: click the Replace All tool in the toolbar.


D8b.4

Free Body Cuts

Free body cuts display the resultant forces and moments (or heat flux in the case of

thermal analyses) transmitted across a selected surface of your model. Free body cuts

may follow element boundaries or may be computed from arbitrary model boundaries as

defined by view cuts.

To create a free body cut based on a view cut:

1. Make only the manifold visible (repeat step 1 of the previous section).

2. Create an X-Plane view cut and set the position to 34.5.

3. In the View Cut Manager, toggle on the option to create a free body cut on the

view cut, as shown in Figure D8b–3.

Figure D8b–3 Free body cut at end of third step


D8b.5

To plot the force history at a free body cut:

1. In the Results Tree, double-click XYData.

2. In the Create XY Data dialog box that appears, select Free body as the data

source and click Continue.

3. In the XY Data from Free Body dialog box, do the following:

a. Select Force as the entity and Resultant magnitude as the component.

b. Click Plot.

The plot appears as shown in Figure D8b–4.

Figure D8b–4 Force history at free body cut

4. Restore the visibility of the entire model and suppress the view and free body

cuts.


D8b.6

Opening Multiple Output Database Files

You can open and work with multiple output database files at the same time in

Abaqus/CAE. To open another output database:

1. From the main menu bar, select File→Open. Select

indentfoam_std_visco_2.odb, and click OK in the Open Database dialog

box.

2. Create another viewport by selecting Viewport→Create from the main menu.

By default, this viewport will open with the current output database file.

3. The size of each viewport can be adjusted as necessary (or select Viewport→Tile

Vertically to create the viewports shown in Figure D8b–5).

4. In the first viewport, display the manifold model.

Figure D8b–5. Opening multiple output database files

X-Y Plotting

X-Y plot options

For the elastomeric foam model:

1. In the Results Tree, expand the History Output container underneath the output

database named indentfoam_std_visco_2.odb.

2. Filter the container according to *LE22*.

3. Click mouse button 3 on LE22 in Element 1 Int Point 1. From the menu that

appears, select Save As and name the curve LE22. Plot the variation of LE22

with time, as shown in Figure D8b–6.


D8b.7

Figure D8b–6. X-Y plot showing the variation of strain with time

4. To review the different options available for X–Y plotting, do the following:

a. Zoom in/out and pan the plot. Note that the chart size remains fixed while

the scale of each axis increases or decreases accordingly, as shown in

Figure D8b–7.

Figure D8b–7. Zoomed-in X-Y plot

As you drag the mouse over the plot, different regions are highlighted. By

double-clicking any of these pre-selected regions, you gain direct access to the

corresponding plot options (this is an example of direct object action).


D8b.8

b. Double-click anywhere on the chart to open the Chart Options dialog

box.

In the Grid Area tabbed page, select Square as the size and drag

the slider to 80. From the list of auto-alignments, choose the one

that places the chart in the center of the viewport.

In the Grid Display tabbed page, change the chart fill color to

light gray.

c. Double-click the legend to open the Chart Legend Options dialog box.

In the Area tabbed page, toggle on Inset. In the viewport, drag the legend

over the chart, as shown in Figure D8b–8.

Figure D8b–8. Repositioned legend

d. Double-click either axis to open the Axis Options dialog box. Increase

the number of Y-axis minor tick marks per increment to 2 (simply increase

the count; the change is reflected automatically). Reset the plot scale by

clicking the auto-fit tool in the dialog box for each axis (select each

axis in turn and click the icon).

Alternative: Click in the toolbar to reset both axes simultaneously.

e. Expand the list of plot option icons in the toolbox:

f. Examine the remaining options. Add the following plot title:

Strain vs. Time. Double-click the plot title to open the Plot Title

Options dialog box. In the Area tabbed page, toggle on Inset. In the

viewport, drag the plot title above the chart, as shown in Figure D8b–9.


D8b.9

Figure D8b–9. Plot with Title

g. Click the curve options icon in the toolbox to open the Curve Options

dialog box. Change the legend text to Element 1 and toggle on Show

symbol. Set the symbol frequency to 2. Reposition the legend. The final

plot appears as shown in Figure D8b–10.

Figure D8b–10. Final plot


D8b.10

Multiple axes

1. Now filter the History Output container according to *S22*. Click mouse button

3 on S22 in Element 1 Int Point 1. From the menu that appears, select Save As

and name the curve S22. Plot the variation of S22 with time.

The two curves appear underneath the XYData container of the Results Tree.

2. Plot the curves simultaneously.

Separate axes appear for each curve. Each is labeled according to variable type.

3. Double-click any axis to open the Axis Options dialog box. The Y Axis region of

the dialog box allows you to choose which Y-axis to modify, as shown in Figure

D8b–11. You can modify multiple axes simultaneously (by selecting more than

one of a given type) or individually.

Figure D8b–11. Options for multiple axes

4. Place the Stress axis on the right side of the plot (in the Axes tabbed page, select

Max Edge as the placement). Change the font size for all axes to 14 (change the

Y-axes simultaneously). Suppress the visibility of the legend and clear the plot

title. Turn off the plot symbols. The resulting plot is shown in Figure D8b–12.

Figure D8b–12. X-Y plot with multiple axes


D8b.11

Combining X-Y plots

1. To create a stress-strain curve from the two curves defined earlier:

a. In the Results Tree, double-click the XYData container. In the Create XY

Data dialog box, select Operate on XY data and click Continue.

b. In the Operate on XY Data dialog box, select combine(X,X) under

Operators (observe that many different operators are available). The

expression text field is highlighted.

c. Now, select LE22 under Name and click Add to Expression. Next, select

S22 under Name and click Add to Expression. Save the curve as

stress-v-strain.

d. Plot the new curve; place the Stress axis on the left side of the plot and

edit the plot title to read Stress vs. Strain, as shown in Figure D8b–

13.

Figure D8b–13. Stress vs. strain plot


D8b.12

Overlaying results

You will compare the deformed shape of the elastomeric foam model at different times

during the simulation by overlaying deformed shape plots.

Display the elastomeric foam model in the viewport and do the following:

1. Create a deformed model shape plot for step 2, increment 0. Set the render style to

shaded and change the fill color to red.

2. From the main menu bar, select View→Overlay Plot.

3. In the Overlay Plot Layer Manager, click Create to create a plot layer named

red.

4. Create a deformed model shape plot for step 2, increment 10.

a. Set the fill color to blue.

b. In the Overlay Plot Layer Manager, click Create to create a new plot layer

named blue.

5. Create a deformed model shape plot for the last increment of step 2.

a. Set the fill color to orange.

b. In the Overlay Plot Layer Manager, click Create to create a new plot layer

named orange.

6. In the Overlay Plot Layer Manager, click Plot Overlay.

Layers are plotted in the viewport in the order in which they appear in the

Overlay Plot Layer Manager (the last layer in the manager is the topmost layer

in the viewport). By default, the layers are plotted directly on top of one another,

which sometimes results in undesirable visual effects.

You will offset and re-order the layers to eliminate these effects.

7. Shift the layers by dragging the Layer offset slider to a small positive number

(.01).

8. Move the orange layer up one level so that it does not obscure the blue layer. The

final figure is shown in Figure D8b–14.

Figure D8b–14. Overlay of deformed shape plots

The bottom layer corresponds to the

configuration at the beginning of the

step; the top one to the state at an

intermediate time; and the middle

one to the end of the step.


D8b.13

Animating Results

The component images of an animation consist of either deformed shape plots, contour

plots, or symbol plots. Here we will animate the contour plot. We will first review the

two types of animations available in Abaqus/CAE.

Time History Animation

In a time history animation Abaqus/CAE creates the images by redrawing the deformed

shape for every frame of the selected steps that are stored in the output database. Each

image in a time history animation displays the actual analysis results.

Scale Factor Animation

In a scale factor animation Abaqus/CAE creates all the images in a sequence from a

single frame of a step. This is useful for simulating, for example, the vibration modes

computed in an eigenvalue analysis.

In this demonstration we will animate the Mises stress field in the elastomeric foam by

doing the following:

1. Return to the single plot state for the elastomeric foam model.

2. Create a contour plot of Mises stress on the deformed shape.

3. Select Animate→Time History from main menu bar.

The time history animation of the Mises stress field appears in the viewport.

Save the animation (Animate→Save As) while the animation is running.

Documents

Demonstration 8b Visualizing Results