Distributed Mass

Apply distributed mass in SimSolid.

Purpose

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:
  • Learn how to apply distrubuted mass bu total area or mass per area.

Model Description

The following model file is needed for this tutorial:
  • DistributedMass.ssp


Figure 1.
This file has the following specifications:
  • Material is set to Steel for all parts.
  • Regular connections with 3mm gap and penetration tolerance.
  • Modal analysis is pre-defined.

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 DistributedMass.ssp
  4. Click OK.

Option 1: Apply Distributed Mass by Total Mass

Use total mass to apply distributed mass to the model.

This is one of two methods for applying distributed mass. To instead apply using mass per area, see Option 2: Apply Distributed Mass by Mass Per Area.

  1. On the main window toolbar, select (Clip assembly with plane).
    This will allow you to see the inner faces of the vessel.
  2. In the Project Tree, click on the Modal 1 modal analysis branch.
  3. On the Analysis Workbench, click (Distributed Mass).


    Figure 3.
  4. Select the inner faces of the vessel as shown in orange in Figure 4.
    Figure 4.
  5. Set Total mass.
    1. In the Distributed mass dialog, select the Total mass radio button.
    2. In the text box, enter 50.
  6. Click OK.

Option 2: Apply Distributed Mass by Mass Per Area

Use total mass to apply distributed mass to the model.

This is one of two methods for applying distributed mass. To instead apply using total mass, see Option 1: Apply Distributed Mass by Total Mass.

  1. On the main window toolbar, select (Clip assembly with plane).
    This will allow you to see the inner faces of the vessel.
  2. In the Project Tree, click on the Modal 1 modal analysis branch.
  3. On the Analysis Workbench, click (Distributed Mass).


    Figure 5.
  4. Select the inner faces of the vessel as shown in orange in Figure 4.
    Figure 6.
  5. Set Mass per area.
    1. In the Distributed mass dialog, select the Mass per area radio button.
    2. In the text box, enter 8.6173.
  6. Click OK.

Run Analysis

Solve the analysis.

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

Review Results

Plot the displacement contour.

  1. On the Analysis workbench toolbar, click the (Results plot) icon.
  2. Select Displacement Magnitude.
    The Legend window will open and display the contour plot. The Frequency (Hz) window will open and display the modes.
    Figure 7.

Compare Results With and Without Distributed Mass

Run the analysis without distributed mass and compare the results.

  1. Create a second modal analysis.
    1. In the Project Tree, right-click on Modal 1.
    2. Choose Copy from the context menu.
      Figure 8.
      Modal 2 will appear in the Project Tree.
  2. Remove distributed mass from Modal 2.
    1. In the Project Tree, expand the Modal 2 branch.
    2. Under Constraints, right-click on Distributed mass 1 and choose Delete from the context menu.


    Figure 9.
  3. Solve Modal 2.
    1. In the Project Tree, ensure Modal 2 is selected.
    2. On the Analysis Workbench, click (Solve).
    The Results branch will appear under the Modal 2 branch in the Project Tree.
  4. Plot Displacement Magnitude for Modal 2.
    1. On the Analysis workbench toolbar, click the (Results plot) icon.
    2. Select Displacement Magnitude.
  5. In the Project Tree, click between the Results branches for Modal 1 and Modal 2 to compare the Displacement Magnitude plots.


    Figure 10. Results with Distributed Mass


    Figure 11. Results without Distributed Mass