To create or edit an initial velocity field:

Display the velocity field editor using one of the following methods:

To create a new velocity field, follow the procedure outlined in “Creating predefined fields,” Section 16.8.3 (Category: Mechanical; Types for Selected Step: Velocity).

To edit an existing velocity field using menus or managers, see “Editing step-dependent objects,” Section 3.4.12.

Note:  You can create or edit an initial velocity only in the initial step.

Click the arrow to the right of the Definition field, and select the option of your choice from the list that appears:

Select Translational only to define an initial translational velocity only.

Select Rotational only to define an initial rotational velocity only.

Select Translational & rotational to define both an initial translational velocity and an initial rotational velocity.

If you selected the Translational only definition option, enter the magnitudes for the initial translational velocities in the 1-, 2-, and (if you are working in three-dimensional space) 3-directions in the V1, V2, and (if applicable) V3 text fields. (If you leave a text field blank, an initial translational velocity of zero is assigned to that degree of freedom by default; the velocity must be defined in at least one direction.)

If you selected the Rotational only definition option:

Enter the magnitude of the angular velocity (in radians/time) in the Angular velocity text field.

Define the axis of rotation.

For three-dimensional models, enter the x-, y-, and z-coordinates, separated by commas, of the points in the Axis point 1 and Axis point 2 text fields.

For two-dimensional models, enter the x- and y-coordinates, separated by a comma, of the point in the Axis point text field. Rotation is assumed to be about the positive z-axis at the specified point.

For axisymmetric models, enter the radius in the Axis radius text field. Rotation is assumed to be about the positive z-axis at the specified radius.

If you selected the Translational & rotational definition option, follow the instructions in both Steps 3 and 4.

Click OK to save your data and to exit the editor.