Performing Your First Analysis in FEBio Studio
This tutorial will several basic methods of analyzing the result of an FEBio simulation in FEBio Studio.
Opening the Simulation Output
- Select the new job entitled “job1” that was added to the bottom of the Model Tree located on the left side of your screen.
- Under the Properties section, click the button labeled Open in FEBio Studio.
Viewing the Model’s Animation
It is always a good idea to watch the simulation’s animation before attempting further analysis. This will give you context for the data that you will extract and in many cases it will help you to identify and mistakes you may have made when preparing the simulation.
- Locate the animation toolbar near the top of the window . If you cannot locate it, ensure that it is enabled by right clicking anywhere on the toolbar and ensuring that the Animation bar is checked. If only part of the toolbar is visible either enlarge your PostView window, or click on the double arrow icon on the left side to expand the toolbar and see all of the options.
- Press the Play button to watch the animation. By default the animation will loop and will continue to play until the play button is pushed again. If you are viewing the simple tensile test that was created in the previous tutorials, you should see the box elongate along the x direction.
- The other blue icons on the toolbar change the currently selected time step to the first, previous, next, or last. Familiarize yourself with the functionality of these buttons.
- The Time Dialog box can be opened by clicking on the time dialog box button . In this box, various animation settings can be changed. Take some time to familiarize yourself with these settings.
Visualizing Data with the Color Map
The Color Map is a useful method of visualizing the spatial distribution of a number of variables.
- The Color Map can be enabled in one of two ways. On the top toolbar locate the dropdown menu that is next to a grayed-out icon showing concentric circles . From this menu, select stress -> Effective stress. Alternatively in the Model tab on the left side of the window click on the arrow next to job1 to see more options and then select Color Map. Then in the Properties box that appears below click on the dropdown menu for the Data field property and select stress -> Effective stress.
- If the model’s animation is not currently playing, press the play button. Watch as the distribution of effective stress is shown on the model for each time step.
- By default, the range of the values in the Color Map dynamically changes for each time step. To set the Color Map’s range to be static locate the property Range type in the Properties box for the Color Map, and select static from the dropdown menu. Allow the model animation to run through one complete cycle during which time the Color Map’s range will update to span the range of values in the simulation. After the first cycle, the range should be static.
- By default, FEBio only records stress for each element in the model, not each node. The default behavior of the Color Map in FEBio Studio is to smooth out the resulting discontinuities by interpolating values for each node. To see the raw element data in the Color Map locate the Nodal Values property in the Color Map’s property box and select No.
Viewing Data Graphically
- The graph window will plot information for the current selection. Nodes, edges, faces, and elements may be selected by clicking on the appropriate icon in the Selection toolbar at the bottom of the screen . Select a single element from the model by clicking anywhere on the model.
- To open a new graph click on the New Graph button in the toolbar , select Post -> New Graph from the main menu, or press F3.
- From the Type dropdown menu on the graph window select Line. Select Time from the X dropdown menu, and stress -> Effective stress from the Y dropdown menu. A plot of effective stress vs time should appear on your graph for your currently selected element.
- The plot will automatically update to if your selection is changed. Select a few more elements by holding down the shift key and clicking in various locations on your model. You should now see a plot for each element.
- You may also plot variables against one another. From the Type dropdown menu select Scatter and from the X dropdown menu select Lagrange strain -> effective Lagrange strain. The stress-strain response of the material is now shown on the graph. Because the material is isotropic and linear, the pots for each of the selected elements will be shown as overlapping straight lines.
- To copy the information currently displayed on your graph, click the Copy button at the top of the graph window. The data can then be pasted directly into a text document, or most spreadsheet applications such as Microsoft Excel.