Creating Buckle Mode Sensors

Buckle mode sensors enable you to create eigenvalue parameters for each mode of a buckle step result to estimate the critical buckling loads of stiff structures.

The buckle mode sensor calculates the eigenvalues and the corresponding eigenvectors for the number of buckle modes specified before analysis. The magnitude of the scalar eigenvalue is called the Buckling Load Factor (BLF), and the computed displacement eigenvector is referred to as the buckling mode or mode shape. Based on the first positive eigenvalue, you can analyze whether or not buckling will occur due to the applied load.

Before you begin: The simulation must be complete and contain one or more buckle mode steps.
  1. From the Visualization section of the action bar, click Create Buckle Mode Sensor .
    The Buckle Mode Sensor dialog box appears.
  2. Optional: Customize the Sensor name.
  3. In the Frame Selector list, specify the steps for which the buckle mode sensor should return data. Select All frames or select a specific frame or frame set in which to measure the output results.

    Use the icon to select new frame ranges in the Frame Selector dialog box. You can define a custom frame range with unique combinations of mode or frequency settings. Once created, frame selection features are available in the Frame selector list in the Sensor dialog box. Click to edit the frame selection feature.

  4. Click OK.
    The new buckle mode sensor is created. Buckle mode sensors are listed in the Feature Manager and in the tree. Knowledgeware parameters containing eigenvalues are created for each mode selected in the Frame Selector dialog box. Use the following table to interpret the Buckling Load Factor:
    BLF ValueBuckling StatusDescription
    >1Not predictedThe applied loads are less than the estimated critical loads.
    =1PredictedThe applied loads are exactly equal to the critical loads.
    <1PredictedThe applied loads exceed the estimated critical loads.
    -1 < BLF <0PossibleBuckling is predicted if you reverse the load directions.
    -1Possible Buckling is expected if you reverse the load directions.
    <-1Not predictedThe applied loads are less than the estimated critical loads, even if you reverse their directions.

You can view, edit, or delete buckle mode sensors from the Feature Manager or from the tree.

You can view the knowledgeware parameters associated with a buckle mode sensor by double-clicking List.n in the Buckle Mode Sensor folder in the tree.