Transforming or Duplicating a Local Coordinate System

Simcenter STAR-CCM+ allows you to transform a local coordinate system to a new location using a coordinate transform, translation, or rotation. You can also duplicate a coordinate system. You access these actions through a right-click menu on the local coordinate system node.

Coordinate Transform

To apply a coordinate system transform:

  1. Right-click and select Transform System > Coordinate Transform....


  2. In the Coordinate System Transform dialog, select the source coordinate system From Coordinate System and target coordinate system To Coordinate System.


  3. Click OK.

    In the following example, this operation transforms Cartesian 1 from the laboratory system to local coordinate system Cartesian 2 with the internal steps:

    • Cartesian 1 is rotated about the origin of the laboratory system with a rotational vector that rotates the laboratory system to match the axis directions of Cartesian 2.
    • The rotated Cartesian 1 is translated with a translational vector that moves the laboratory system to match the origin of the Cartesian 2.
    The local coordinate system Cartesian 1 is defined in the laboratory system with the following properties:
    X Axis Input [1.0, 0.0, 0.0]
    Vector on X-Y Plane Input [0.0, 1.0, 0.0]
    Origin [0.0, 0.1, 0.0]
    Reference System Laboratory (read-only)
    The local coordinate system Cartesian 2 is defined in the laboratory system with the following properties:
    X Axis Input [1.0, 1.0, 0.0]
    Vector on X-Y Plane Input [1.0, 0.0, 1.0]
    Origin [0.0, -0.1, 0.0]
    Reference System Laboratory (read-only)
    The transformation of Cartesian 1 from the laboratory system to Cartesian 2 is demonstrated below:



    After the transformation, the properties of Cartesian 1 are:
    X Axis Input [0.7071068, 0.7071068, 0.0]
    Vector on X-Y Plane Input [0.408248, -0.408248, 0.816496]
    Origin [0.0408248, -0.1408248, 0.0816496]
    Reference System Laboratory (read-only)

Translation

To translate the coordinate system:
  1. Right-click and select Transform System > Translate....
  2. In the Translate Coordinate System dialog, enter the component distances by which you wish to translate the local coordinate system.

    Distances can be either positive or negative, and can be entered in any valid length unit.

  3. Click the Reference System drop-down list for a choice of existing coordinate systems.
  4. Click OK.

Rotation

To rotate the coordinate system:
  1. Right-click and select Transform System > Rotate....
  2. In the Rotate Coordinate System dialog, enter the angle by which you wish to rotate the local coordinate system, and the components of the vector to rotate it around.

    The Reference System drop-down list offers a choice of coordinate systems in the simulation.

  3. Click OK.

Duplicate System

To duplicate a selected coordinate system within another coordinate system:

  1. Right-click and select Duplicate System to....
  2. In the Duplicate Coordinate System dialog, select the target coordinate system To Coordinate System.


  3. If there is a hierarchy of local subsystems within the source coordinate system, and you wish to include these in the duplicate system, activate Include Local Systems.
  4. Click OK.

    The copy has the same definition with respect to the laboratory system as the original coordinate system.





NoteIn DFBI applications, you can create a duplicate coordinate system under the local coordinate system of the 6-DOF body if needed. The duplicate moves together with the body coordinate system.