Performing a Numerical Analysis

You can perform a numerical analysis to compute the area, mass, center of gravity and mass on a ply, a sequence, a plies group, or a stacking.

Notes:
  • This task is available in Composites Design and Composites Manufacturing Preparation.
  • You can run the numerical analysis
    • On zones (that is, zones groups or zones) or on plies (that is, stacking or plies) but you cannot select a mix of zones and plies.
      • However, an analysis of zones does not take cut-pieces into account.
      • If you select a zones group, all the zones that it contains are analyzed.
      • If you select Take cut-pieces into Account for a ply containing cut-pieces, the computation is made from the cut-pieces geometries. Otherwise, it is made from the ply geometry.
    • On a cut-piece. Even if Persistent is selected, no numerical analysis feature is created under each cut-piece.
    • On a grid
      Note: The ply drop along the staggering and the corresponding added mass are not taken into account.
  • When you run a numerical analysis to find differences between two identical or similar parts (different versions of the same part, manufacturing part), a numerical inaccuracy of around 1% must be taken into account for computed areas, especially when plies have cut-out or holes. Such a difference is to be ignored.
  • Select the Persistent check box to store the result of the numerical analysis of plies in the representation.
  • You cannot store the result of a numerical analysis of zones in the representation, but you can export it.

  1. From the Review section of the action bar, click Numerical Analysis .
    The Persistent and the Take cut-pieces into account check boxes are not active when you have selected zones.
  2. Select the element to analyze:
    • A grid
    • A stacking or portion of it
    • A zones group or portion of it.

    • Multiselection of entities is available.
    • in the dialog box that appears gives access to the Stacking Management.

    The analysis is automatically started, displaying the results under Analysis.
  3. If required and possible, select the Take cut-pieces into Account check box.
    The analysis is updated with the information concerning the cut-pieces.
    Notes:
    • The values increase as the result of the plies superposition.
    • To compute the Area, and the weight and balance, Numerical Analysis considers that all plies lie directly on the support surface. This means that the area of an individual ply is computed by trimming the support surface by that ply contour. This assumption impacts all related properties (such as the center of gravity). Also the thicker the stacking, the less accurate the result is.

    The numerical analysis of all the plies can now be exported in an external file (.xls or .txt).

  4. If required, select the Take Core thickness into Account check box.

    • When Take Core thickness into Account is not selected, the computed area for plies looks like this

    • When Take Core thickness into Account is selected, the computed area for plies looks like this

    The analysis is updated with the information concerning the Core Thickness.
  5. If required, select the Compute analysis with ply and core shape simulated at thickness check box.

    • Compute analysis with ply and core shape simulated at thickness is more time consuming but also more precise.
    • Compute analysis with ply and core shape simulated at thickness includes Take Core thickness into Account

    1. Optional: Edit the Refinement Factor.

      Refinement Factor improves the accuracy of the tessellation used to compute the numerical analysis, but has an impact on computation time. The lower the value, the greater the accuracy of results, but also the computation time. The minimum value is 0.02. The maximum is 10. The default is 1.

    2. Optional: Select the Display normals check box.

      The normals used for elevating each vertex of the tessellation triangles are displayed. The normals direction and their density help you specify the Refinement Factor.

    3. Press Compute.
    Messages are displayed if there are errors on plies, or if a core does not lie completely on the support surface.
    Notes:
    • Results of this option are not persistent: you have to export them to keep them.
    • If plies are defined on two overlapping support surfaces, the thickness of plies on first surface is not considered for plies lying on the second surface.
      Recommendation: In such a case, define all the plies on a larger single surface.
    • If the top surface computed from Plies Group.1 is used to define plies from Plies Group.2, the thickness of plies added to Plies Group.1 after the computation of the top surface is not taken into consideration for the computation of plies from Plies Group.2.
      Recommendation: In such a case, recompute the top surface after having added plies to Plies Group.1, and define the plies from Plies Group.2 on the new surface.
  6. Click ... to enter a storage directory and file name to export the data. Click Export.
    An information message is displayed when data is successfully exported.

    Here is the information contained in the external file:

    • For zones:
      • Zone name
      • Thickness (mm)
      • Number of layers
      • Area (m2)
      • Volume (m3)
      • Volumic Mass (Kg)
      • Aerial Mass (Kg)
      • Centre of Gravity-X (mm), Centre of Gravity-Y (mm),Centre of Gravity-Z (mm)
      • Cost.
    • For plies:
      • Ply Group
      • Sequence
      • Ply/Insert
      • Material
      • Direction
      • Area (m2)
      • Volume (m3)
      • Volumic Mass (Kg)
      • Aerial Mass (Kg)
      • Centre of Gravity-X (mm), Centre of Gravity-Y (mm),Centre of Gravity-Z (mm)
      • Cost.

  7. Select a Material to filter the results.

    Filtering through Material is only possible if you have selected at least a stacking as input.

  8. If available, select the Persistent option to featurize and display the analysis in the tree.

The numerical analysis is stored under the representation if you have selected plies. The Numerical Analysis element is displayed in the stacking node under each sequence containing the selected material.