Defining an Average Surface (Turbomachinery)

In Simcenter STAR-CCM+, the average surface part evaluates the average or weighted average of a chosen scalar or vector field function over a 3D region or part in the context of an axisymmetric parameterization. This derived part is typically used for post-processing results of a turbomachinery analysis.

With this derived part, you can produce a 2D data set that is made up of the averaged 3D solution. From this data set, it is possible to perform any post-processing that is meaningful with a 2D data set such as producing scalar scenes, vector scenes, and line graphs. Since this is a 2D data set, you can view the average on a flat 2D plane.

The average part is computed in a parameterized coordinate system based off the cylindrical coordinate system where the radial axis direction is (0, 1, 0) and the tangential axis direction is (-1, 0, 0). (That is, the average direction is always the theta direction or circumferential direction.)

This procedure assumes that you already have an axisymmetric parameterization defined in your simulation.

  1. Follow the general procedure outlined in the section, Defining Derived Parts General Workflow. Choose the menu option, New Part > Average Surface...
  2. Specify the input parts and display option as described in the section, Defining Derived Parts General Workflow.
  3. Complete the average surface definition by specifying the following properties:
    1. Parameterization: Select a parameterization. See Parameterization of Volume of Revolution.
    2. Weighting: To determine whether you use a weighted average, set this property to one of the following:
      • None
      • Scalar Function
      • Mass
      • Mass Flow

      When using Scalar Function, you specify the scalar function by selecting it in the Weighting function property of the Weighting sub-node of the derived part node, or in the Weighting property of the in-place dialog.

    For more information on the available properties, refer to the section Average Surface Properties.

    This derived part appears as a flat plane that is placed at the minimum circumferential value of all input parts.