SN Sequential Fatigue

Create an SN Sequential fatigue loadcase.


SimSolid performs meshless structural analysis that works on full featured parts and assemblies, is tolerant of geometric imperfections, and runs in seconds to minutes. In this tutorial, you will do the following:
  • Create SN Sequential Fatigue loadcase.
  • Manually create sequences.
  • Solve and review results.

Model Description

The following model files are needed for this tutorial:
  • SNManualSequences.ssp

Figure 1.
The project (.ssp) file has the following specifications:
  • Material is set to Steel for all parts.
  • Linear static subcase with results is included.

Open Project

Open the SimSolid project file.

  1. Start a new SimSolid session.
  2. Click the (Open Project) icon.

    Figure 2.
  3. In the Open project file dialog, choose SNManualSequences.ssp
  4. Click OK.

Review Model

Review the model and loadcases.

  1. In the Project Tree, expand the Structural analyses branches.
  2. Expand the Loads&Constraints branch and review the loads.

    Figure 3.
  3. Click (Results plot) and choose the desired plot to review regions of high stress.

Add Fatigue Material Properties

Edit material to include fatigue properties.

If an SN curve has already been assigned, skip this step. Check the assigned material properties by right-clicking Assembly in the Project Tree and selecting Show > Materials.

  1. In the main menu, click Settings > Material database.

    Figure 4.
  2. In the dialog, click Edit current.

    Figure 5.
  3. In the Generic Materials group, right-click Steel and select Copy from the context menu.
  4. Edit the copied material.
    1. Select Steel1 - Copy_0.
    2. Click Edit material.
  5. Add fatigue curves.
    1. In the editing field of the dialog, expand the Fatigue properties branch and click Add stress-life (SN) curve....
    2. Verify the Curve definition method is set to Estimate from UTS.
  6. Click Apply.
  7. Click Save.

Create SN Sequential Fatigue Loadcase

Create SN Sequential Analysis.

  1. On the main window toolbar, click (Fatigue analysis).
  2. In the drop-down menu, select SN Sequential.

    Figure 6.
    The new analysis will appear in the Project Tree. The SN Sequential Workbench items are listed.

    Figure 7.

Create Sequences

Create sequences for the analysis.

  1. On the workbench toolbar, click (Create sequences).
  2. In the Sequence setup window, click Add row and pick load cases in the order shown in Figure 8.

    Figure 8.
  3. Set the Load scale to 50.
  4. Set Sequence repeats to 10,000.
  5. Click OK.
    The sequences appear in the Project Tree. You can create multiple sequences for each SN Sequential loadcase.

    Figure 9.
  6. Optional: Double-click on a sequence to review/edit in the dialog.

Run Analysis

Solve the analysis.

  1. In the Project Tree, open the Analysis Workbench.
  2. Click (Solve).

Review Results

Plot fatigue damage and pick info for the fatigue subcase.

  1. In the Project Tree, Select the Fatigue SN Sequential 1 subcase.
  2. On the Analysis Workbench, select > Fatigue damage.
    The Legend widow will open and display the contour plot. The Sequences window will open and list sequences.
    Figure 10.

    Note: If there are multiple sequences in the load case, you can plot damage for each event or you can plot cumulative damage.
  3. Pick info.
    1. On the Results Workbench toolbar, click (Pick info).
    2. In the modeling window, select points of interest.
    3. In the Pick info dialog, for Sequence, select Total from the drop-down menu to view cumulative damage, or select the individual sequence of interest.

      Figure 11.