Defining the Sweeping and Pitching Motions

The sweeping motion is a rigid rotation about the stroke plane normal. The sweep angle ϕ varies harmonically with time with an amplitude of 70°. The pitching motion is a rigid rotation about the wing longitudinal axis. The pitch angle α is constant for most of the forward and backward strokes, varying linearly with time only during stroke reversals (supination and pronation). In this tutorial, you import a table that contains values of the stroke and pitch angles at discrete values of flapping cycle time, ( t F C , ϕ , α ) i . To calculate the sweep and pitch angles at each time-step, you create reports that interpolate the imported tabular data.

To import the motion data provided for this tutorial:

  1. Right-click the Tools > Tables node and select New Table > File Table.
  2. In the Open dialog, navigate to the solidStress folder of the downloaded tutorial files, select wingMotion.csv and click Open.
To extract the sweep angle at the current time-step from the imported tabular data:
  1. Create an expression report named StrokeAngle, with the following settings:
    Property Setting
    Dimensions Angle
    Units deg

    In the table, the discrete angle values are specified in radians. Simcenter STAR-CCM+ converts radians to the specified units (in this case, deg) when evaluating the report.

    Definition interpolateTable(@Table("wingMotion"), "Flapping Cycle Time", LINEAR, "Stroke Angle", ${FlappingCycleTimeReport})
Complete the setup for the sweeping motion:
  1. Expand the Tools > Motions > Wing Sweeping node and set the following properties:
    Node Property Setting
    Wing Sweeping Rotation Specification Rotation Angle
    Rotation Angle Rotation Angle ${StrokeAngleReport}
    Rotation Axis Direction [0.0, 0.0, 1.0]
    Origin [0.0, 0.0, 0.0] m (default)
To extract the pitch angle at the current time-step from the imported tabular data:
  1. Create an expression report named PitchAngle, with the following settings:
    Property Setting
    Dimensions Angle
    Units deg
    Definition interpolateTable(@Table("wingMotion"), "Flapping Cycle Time", LINEAR, "Pitch Angle", ${FlappingCycleTimeReport})
Complete the setup for the pitching motion:
  1. Expand the Motions > Wing Sweeping > Superposing Motions > Wing Pitching node and set the following properties:
    Node Property Setting
    Wing Pitching Rotation Specification Rotation Angle
    Rotation Angle Rotation Angle ${PitchAngleReport}
    Rotation Axis Direction [1.0, 0.0, 0.0]
    Origin [0.0, 0.0, 0.0] m (default)
  2. Save the simulation.