MAC - Load Tab

The MAC utility's Load tab allows you to select and load the reference and correlation files and define the model files to prepare them for a MAC analysis.

Figure 1. MAC Utility - Load Tab - Transformation Sub-tab


The following options are available:

File selection

Click the file browser icon for the Reference File and Correlation File fields and select one of the file types listed below. Upon selection, click Load.
  • H3D (*.h3d)
  • OP2 (*.op2)
  • UNV (*.unv)
  • ODB (*.odb)

Transformation

The first step in performing a MAC analysis is to ensure that both the geometry of the finite element model and the associated results are transformed into an overplayed position in a common coordinate system.
This can be done using the transformation capability, found in the Transformation tab:


Figure 2. Transformation Tab
  1. Under Reference node Selection, select three nodes from the reference model.
    • Click the node selector (N1, N2, N3) to activate it, then select the node on the model in the modeling window.
    • You can also double-click on a node selector to enter a node ID directly into the Select by ID dialog.
  2. Under Correlation node Selection, select three corresponding nodes from the correlation model, which will serve as the destination locations for the nodes selected in the step 1.
  3. Click Transform to correlate the two models using scaling and positioning.

    The entire reference model is transformed as a rigid body based on the transformation defined by the three nodes in step 2.

  4. Results associated with the reference model are transformed in the same way as in step 3.
  5. Click Save Model to save the transformed model.

NodePairs

The next step is to identify the node pairs between the reference and correlation models.
Use the NodePairs tab to filter nodes with different options.


Figure 3. NodePairs Tab
Pair by scan
Identify the node pairs by scanning within the user-specified tolerance.
Pair by ID
Identify the node pairs with matching IDs.
Selection by
Submodels can be defined based on finite element (FE) components, user-defined node sets, or a HyperWorks assembly module structure (requires a module ID file).

From the Selection by drop-down menu, select Component, Set, or Assembly.

Reference and Correlation Filters
Click the filter icon, , for the Reference or Correlation filters to filter components to a smaller set of data.
You can show or hide components by moving them to the appropriate column.
hide comps
A list of components that will be hidden in the display. You can move the components from the hide comps list to the show comps list. To do this, select one or more components from the list and click the right arrow to move it to the show comps column.
show comps
The components used for the node pairs. You can move the paths in the show comps list back to the hide comps list to reduce the list of components. You can move the modes from the show comps list to the hide comps list to reduce the list of components. To do this, select one or more components from the list and click the left arrow to move it to the hide comps column.
  • Click to select the entire list of components.
  • Click to deselect your current selections.
  • Click to exchange the currently selected components for the unselected components in the list.


Figure 4. Filter Comps Dialog
Element Selection
Select Mass and/or Plotel and enter a length filter to identify element configurations.

You can also select 1D, 2D, and 3D elements by activating those check boxes.

Result Set
Structure
Identify the node pairs for only structural modes.
Fluid
Identify the node pairs for only fluid modes.
Coupled
Identify the node pairs for coupled modes.
Tolerance
You can filter nodes in the models based on a user-specified distance tolerance. Enter a node pair tolerance value in the Tolerance field.
Show
Use the Show drop-down menu to display either Mapped Pair or Unmapped Nodes in the 3D modeling window. Nodes in the reference model are mapped with those in the correlation model.
Import/Export
  • Click Import to import a .csv file containing node pairs.
OR
  • Click Export to export node pairs into a .csv file.
Scan
Click Scan to scan the model files for the filters you have defined.
Save
Click Save to save the node pairs you have identified.
Apply
Once the node pairs between the reference and correlation models are finalized, click Apply. The utility automatically goes to the ModesFilter tab.

ModesFilter

Using the ModesFilter tab, you can select modes from the two models based on the load cases, defining a frequency range, or by filtering the frequency values manually.


Figure 5. ModesFilter Tab
Ref and Cor Subcase
Use the Ref Subcase and Cor Subcase drop-down menus to select loadcases for filtering.
Start and End Frequency
Enter a start and end frequency range and click Select to filter the modes in that range.
Reference and Correlation Mode List Columns
Modes can be individually filtered using the filter icon, . Clicking the filter icon displays the Filter Modes dialog.
You can show or hide modes by moving them to the appropriate column.
hide modes
A list of modes that will be hidden from view. You can move the modes from the hide modes list to the show modes list. To do this, select one or more modes from the list and click the right arrow to move it to the show modes column.
show modes
The modes to be displayed. You can move the modes from the show modes list to the hide modes list to reduce the list of modes. To do this, select one or more modes from the list and click the left arrow to move it to the hide modes column.


Figure 6. Filter Modes Dialog
You can also use the following icons to the right of the mode list columns and in the Filter Modes dialog.
  • Click to select the entire list of modes.
  • Click to deselect your current selections.
  • Click to exchange the currently selected modes for the unselected modes in the list.
Animate
To animate a mode, highlight only the mode from the list and click Animate.
Compute Submodel MAC
MAC
Once the MAC calculation is complete, the utility goes to the Display tab.