Applying Uniform Base Motion for a Harmonic Study

To apply uniform base motion for a harmonic study:

  1. Right-click the Load/Restraint folder and select Uniform Base Excitation.
  2. Under Type, do the following:
    1. Select Displacement, Velocity, or Acceleration.
    2. For Face, Edge, Plane for Direction , select a reference entity.
      If you select a planar face or a reference plane, you can specify excitations Along Plane Dir 1 , Along Plane Dir 2 PM_along_plane_dir2.gif, or Normal to Plane .
      If you select an edge, you can specify an excitation along the edge alongedge.png.
  3. Under Displacement, Velocity, or Acceleration, do the following:
    1. For Unit , select the desired unit.
    2. Click the button for a direction and enter a value.
  4. Under Phase Angle, do the following:
    • For Unit, select the desired unit.
    • For Angle, enter a value.
  5. Under Variation with Frequency, select:
    • Constant to specify constant excitation for the full range of operating frequencies.
    • Curve to specify your own variation or select a library curve. Click Edit to modify the curve.
      If the operating frequency limit has a certain range of frequencies starting at a non-zero point (for example: 5 Hz - 500 Hz), include a point at (0, 0) when defining a base excitation curve to run the harmonic study. The software uses a Log-Log interpolation method to interpolate the frequency values that fall between the frequency curve input points. The software converts the input values of the curve to Log-Log scale and interpolates linearly (in the Log-Log domain) to find the values of frequencies that fall between the curve points.
    The uniform base motion is applied to all locations that are restrained in the specified directions. Click Graph to view the variation in all selected directions.
  6. Under Symbol Settings, do the following:
    1. Click Edit Color to select a color.
    2. Set Symbol Size .
  7. Click .