Specifying damping for mechanical contact property options

From the main menu bar, select InteractionPropertyCreate.

In the Create Interaction Property dialog box that appears, do the following:

• Name the interaction property. For more information about naming objects, see Using basic dialog box components.

• Select the Contact type of interaction property.

Click Continue to close the Create Interaction Property dialog box.

From the menu bar in the contact property editor, select MechanicalDamping.

In the editor that appears, click the arrow to the right of the Definition field, and select an option for determining the dimensionality of the damping coefficient:

• Select Damping coefficient to specify the damping coefficient with units of pressure per relative velocity. For more information, see Specifying the damping coefficient such that the damping force is directly proportional to the rate of relative motion between the surfaces.

• Select Critical damping fraction (Explicit only) to specify a unitless damping coefficient in terms of the fraction of critical damping associated with the contact stiffness; this method is available only for Abaqus/Explicit. For more information, see Specifying the damping coefficient as a fraction of critical damping in Abaqus/Explicit.

Choose an option for specifying the Tangent fraction (the ratio of the tangential damping coefficient to the normal damping coefficient):

• Choose Use default to accept the default tangent fraction value. For Abaqus/Standard the default is 0.0, so the damping coefficient for the tangential direction is zero. For Abaqus/Explicit the default value for the tangent fraction is 1.0, so the damping coefficient for the tangential direction is equal to the damping coefficient for the normal direction.

• Choose Specify value to enter a value for the tangent fraction.

For more information, see Specifying the tangential damping coefficient.

Choose a shape for the curve that describes the relationship between clearance and the damping coefficient:

• Choose Step (Explicit only) if you are performing an Abaqus/Explicit analysis. The damping coefficient will remain at the specified constant value while the surfaces are in contact and at zero otherwise.

• Choose Linear (Standard only) to define a damping coefficient that increases linearly from zero at a particular clearance value ($c_0$) to its full value when the surfaces are in contact.

• Choose Bilinear (Standard only) to define a damping coefficient that increases linearly from zero at a particular clearance value ($c_0$) to its full value when clearance has been reduced to another value ($c$). As clearance continues to decrease from $c$ to zero, the damping coefficient remains constant at its full value.

Enter the appropriate data in the table provided:

• If you are performing an Abaqus/Explicit analysis, enter a value for the damping coefficient or for the critical damping fraction (depending on your selection in Step 5.)

• If you are performing an Abaqus/Standard analysis and selected Linear (Standard only) in the previous step, enter the following:

  • In the first row, enter a value for the damping coefficient.

  • In the second row, enter a value for $c_0$, the clearance at which the damping coefficient is zero.

• If you are performing an Abaqus/Standard analysis and selected Bilinear (Standard only) in the previous step, enter the following:

  • In the first row, enter a value for the damping coefficient.

  • In the second row, enter a value for $c$, the clearance at which the damping coefficient reaches its full value.

  • In the third row, enter a value for $c_0$, the clearance at which the damping coefficient is zero.

Click OK to create the contact property and to exit the Edit Contact Property dialog box. Alternatively, you can select another contact property option to define from the menus in the Edit Contact Property dialog box.