Assigning contact properties for general contact in Abaqus/Explicit | ||
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ProductsAbaqus/ExplicitAbaqus/CAE
Assigning contact properties
The default contact property model in Abaqus/Explicit assumes “hard” contact in the normal direction, no friction, no thermal interactions, etc. You can assign a nondefault contact property definition (surface interaction) to specified regions of the general contact domain.
Contact property assignments propagate through all analysis steps in which the general contact interaction is active.
The surface names used to specify the regions where nondefault contact properties should be assigned do not have to correspond to the surface names used to specify the general contact domain. In many cases the contact interaction will be defined for a large domain, while nondefault contact properties will be assigned to a subset of this domain. Any contact property assignments for regions that fall outside of the general contact domain will be ignored. The last assignment will take precedence if the specified regions overlap.
Input File Usage
CONTACT PROPERTY ASSIGNMENT surface_1, surface_2, interaction_property_name
This option must be used in conjunction with the CONTACT option. It should appear at most once per step; the data line can be repeated as often as necessary to assign contact properties to different regions.
If the first surface name is omitted, a default surface that encompasses the entire general contact domain is assumed. If the second surface name is omitted or is the same as the first surface name, contact between the first surface and itself is assumed. Keep in mind that surfaces can be defined to span multiple unattached bodies, so self-contact is not limited to contact of a single body with itself. If the interaction property name is omitted, the unnamed set of default contact properties in Abaqus/Explicit is assumed. If an interaction property name is specified, it must also appear as the value of the NAME parameter on a SURFACE INTERACTION option in the model portion of the input file.
Abaqus/CAE Usage
Interaction module: Create Interaction: General contact (Explicit): Contact Properties: Individual property assignments: Edit: select the surfaces and the contact property in the columns on the left, and click the arrows in the middle to transfer them to the list of contact property assignments or Global property assignment: interaction_property_name
In Abaqus/CAE you must assign a contact property definition to every general contact interaction; Abaqus/CAE does not assume a default contact interaction property.
Example
The following contact property assignments are specified below for the first step in a general contact analysis:
a global assignment of contProp1 to the entire general contact domain;
a local assignment of contProp2 to self-contact for surf1;
a local assignment of the default Abaqus contact property to contact between surf2 and surf3; and
a local assignment of contProp3 to contact between the entire contact domain and surf4.
SURFACE INTERACTION, NAME=contProp1 FRICTION 0.1 SURFACE INTERACTION, NAME=contProp2 FRICTION 0.15 SURFACE INTERACTION, NAME=contProp3 FRICTION 0.20 STEP Step1 DYNAMIC, EXPLICIT … CONTACT CONTACT INCLUSIONS, ALL EXTERIOR CONTACT PROPERTY ASSIGNMENT , , contProp1 surf1, surf1, contProp2 surf2, surf3, , surf4, contProp3
Changing contact properties
Contact property models for general contact interactions are independent of the steps in which they are used and cannot be modified from step to step. To change the contact properties used in a given step, you must specify a new contact property assignment that refers to a different contact property model.
Example
For example, the following input could be used to change the friction coefficient used for contact between the entire general contact domain and surf4 in the second step of the analysis started in the previous example:
STEP Step2 DYNAMIC, EXPLICIT … CONTACT CONTACT PROPERTY ASSIGNMENT , surf4, contProp2