Creating a 2D dependent mesh

Estimated time to complete: 10–20 minutes

In this tutorial, you will learn how to use the 2D Dependent Mesh command.

1: Setup

  1. On your desktop or the appropriate network drive, create a folder named impeller.

  2. Click the link below:

    Download the part

  3. Extract the file to your impeller folder.

  4. Start Simcenter 3D or NX.

  5. Open impeller_fem1.fem.

2: Reset dialog box memory

The options you select in dialog boxes are preserved for the next time you open the same dialog box within a given session. Restore the default settings to ensure that the dialog boxes are in the expected initial state for each step of the activity.

File

Preferences→User Interface

  • Options

  •   Reset Dialog Memory

  • OK

     
3: Assign the global cyclic coordinate system

The solid body of the impeller has been trimmed to a single blade. You will edit the FEM file to set the global cyclic coordinate system, a cylindrical coordinate system whose Z-axis defines the default axis of rotation for your FEM.

  Simulation Navigator

  •   impeller_fem1.fem

  •   Edit

  •  

  • Use Cyclic CSYS if Defined

  • Specify CSYS

    CSYS of Object

  • OK

     

     

4: Create a 3D mesh collector

  Mesh Collector (Home tab→Properties group)

  • Element Family

    3D

  • Collector Type

    Solid

  •  

    Create Physical (Solid Property)

  • Name

    Aluminum

  •  

    Choose material (Material)

  • Materials

    Aluminum_2014

  • OK

     all dialog boxes
5: Create a 2D mesh dependency

For cyclic symmetry, the radial, tangential, and axial displacements relative to the axis of rotation are identical at equivalent positions on the repeated faces (the faces created during the trimming operation). To model this behavior:

  1. Create a 2D dependent mesh on the repeated faces. Doing so locates the nodes on each face at equivalent positions.

  2. Use the 2D dependent mesh to seed a 3D mesh of the body.

  3. Change the nodal displacement coordinate system to the global cyclic analysis coordinate system.

  4. Couple the degrees of freedom (DOF) for each pair of equivalently positioned nodes lying on the repeated faces.

  2D Dependent (Mesh group→More list)

  • Type

    Symmetric

  • Selecting the first face automatically selects the second face and the appropriate edges.

  • Mesh Type

    Free Mesh

  • OK

     

    The 2D Mesh dialog box appears. Do not close it.

6: Complete the 2D dependent mesh

The 2D Mesh dialog box is open from the previous step.

  • Type

    CTRIA6

  • Element Size

    0.6

  •  

     

  • Export Mesh to Solver

  • OK

     

     

7: Create the 3D mesh

  3D Tetrahedral (Mesh group)

  • Type

    CTETRA(10)

  • Element Size

    0.6

  •  

     

  •  Automatic Creation

    The Solid(1) mesh collector that you created earlier should be automatically selected in the Mesh Collector list.

  • OK

     

     

  Save

File

  • Close→All Parts