Defining an initial velocity field

You can create this type of predefined field to define the initial velocity of the selected region. For more information, see Initial conditions in Abaqus/Standard and Abaqus/Explicit.

Related Topics
Creating predefined fields
Understanding symbols that represent prescribed conditions
Using analytical expression fields
Creating expression fields
In Other Guides
Initial conditions in Abaqus/Standard and Abaqus/Explicit

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

    Note:

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

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

    • Select Uniform to define an initial velocity that is uniform over the region.

    • Select an analytical field to define a spatially varying initial velocity. Alternatively, you can click to create a new analytical field. (See The Analytical Field toolset for more information.)

  3. 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.

  4. 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.)

  5. If you selected the Rotational only definition option:

    1. Enter the magnitude of the angular velocity (in radians/time) in the Angular velocity text field.
    2. 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.

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

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