Including Additional Control Points

In many simulations the control points that contribute to the morpher interpolation field come from boundary vertices. However, you can also specify additional control points—and their associated displacements—by defining point sets within the Point Sets node.

Additional control points can be added to influence the morphing procedure. Once the Motion Specification in at least one region is assigned to Morphing, the Point Sets node appears in the simulation tree. You can then add one or more point sets with their associated displacements without reference to any boundary or region.

To create additional control points and set up their morphing specification:

  1. Right-click the Point Sets node and select New Point Set > [type] where [type] is one of Table, Lattice, Line, Part or Volume Part.
  2. Continue by completing the Edit panel according to the chosen type:
    1. For Table, set Source Table to a previously imported table that contains X, Y Z coordinates for each point, then match the X Data, Y Data, and Z Data properties to their associated columns in the table. Refer to Create Point Set from Table Dialog.


      • To create a position table, you prepare a file containing the position of the control points in a suitable file format, such as .csv (see Tables for more information). The point set is defined as a table containing X, Y, Z coordinates of the points. An example of a pointset.csv table is shown below: 
        X1, Y1, Z1
0.55 0.0 0.025 
0.55 0.0 0.075
0.55 0.0 0.125
0.55 0.0 0.175
0.55 0.0 0.225
0.55 0.0 0.275
0.55 0.0 0.325
0.55 0.0 0.375
0.55 0.0 0.425
0.55 0.0 0.475
      • To import the table, right-click the Tools > Tables node and select New Table > File Table. Navigate to the file, select it, and click Open.
      An example of points created from a table import is as follows:

    2. For Lattice, you define the points by specifying the lattice structure in space with the number of points in each direction. In the Create Point Set from Lattice dialog, set the Origin and Size of the rectangular bounding box and the number of points required in each coordinate direction. You can rotate the lattice around a chosen Rotation Axis by a specified Rotation Angle. Refer to Create Point Set from Lattice Dialog.


      An example is shown as follows:

    3. For Line, you define the start and end points of the line as well as the number of points along it. In the Create Point Set from Line dialog, set the starting point Point 1 and ending point Point 2 as well as the Number of points. Refer to Create Point Set From Part Dialog.
    4. For Part, you define the points with reference to the surface of a chosen part. You can choose derived parts in addition to geometry parts and regions or boundaries. In the Create Point Set from Part dialog, set the following properties as described in Create Point Set from Part Dialog:
      • Input Part
      • Representation
      • Target Point Set Spacing
      • Maximum Number of Points
      • Offset from Part Surface
      NotePoint positions are assigned randomly across the part surface according to the Target Point Set Spacing. You can offset the points from the part surface, but you cannot define the exact position of the points on the surface.
    5. For Volume Part, you define the points within a volume defined by one or more geometry parts (shown within Geometry > Parts). In the Create Point Set from Volume Part dialog, set the following properties as described in Create Point Set from Volume Part Dialog:
      • Input Part—one or more parts that together define the volume within which points are randomly distributed.
      • Representation
      • Maximum Number of Points
      NoteThe points are sampled randomly in the selected volume.
  3. After specifying the point locations, select the Point Sets > [Type] Point Set > Physics Values > Motion Specification node and set Motion to Morphing.
  4. Select the Tools > Motions > Morphing node and verify that the Morphing Order fulfills the association strategy. For more details refer to Morphing Order.
  5. Select the [Type] Point Set > Physics Conditions > Morpher Displacement Specification node and set Specification and the corresponding node referring to Point Sets Physics Values.
  6. To change the settings in the point set, you right-click the created [Type] Point Set and select Edit Point Set.
In the following example, the points defined through a table are set with an incremental displacement X=0.05m each time step.

Backward Compatibility — Restoring Simulations prior to Simcenter STAR-CCM+ Version 15.02

There are two main differences in the control point definition before and after version 15.02:
  • In the previous versions, table-based control points were stationary and did not move with the computed displacement. Therefore, the displacement calculated using target positions in the table was assigned to the morpher iteratively after each iteration or time step. Since version 15.02, the target position is not a iterative quantity and the morpher solver moves control points to their target position within one iteration or time step. For backward compatibility, an extra option Move Legacy Control Point Set is added to the Point Sets > [Type] Point Set > Physics Values node. When you load an old simulation, this option is deactivated and the target positions are assigned to the corresponding Morpher Target Position node using the existing table as illustrated in the image below:


    The restored simulation runs with the converted settings in Simcenter STAR-CCM+ 15.02:



  • The old table is a static list of points where each row dedicates a point. The new displacement profile interprets the table as a 3D vector field. That is, based on the current position of each point, the corresponding displacement values are found dynamically using the nearest neighbor algorithm.