Contacts
The Contact condition enables you to manually define one or more contacts, a type of connection between surface bodies.
By default, Discovery automatically generates contacts and sets them to bonded. You can review these generated contact pairs in the Bonded Contacts (default) review tool. From there, you can change the contact behavior or convert to a joint or sliding contact.
Guidelines
For both manually and automatically defined contacts, Discovery assumes "assembly contact", a small sliding contact solution where the surfaces in contact are near each another and the amount of physical sliding is small. Discovery supports assembly contact applications with load transfer across parts, such as bolted connections or interference fits. However, large sliding contact applications, such as snap-fit insertions or compression of O-ring seals, are not supported by Discovery.
For automatically generated bonded contacts in either the Explore or Refine stage, the contacts are bonded if the contact surfaces are separated by a distance less than or equal to the Maximum detection distance shown in the Bonded Contact Review tool. This method ensures that any automatically detected bonded contacts are bonded during the solution.
Specifying either frictionless or frictional contact results in a nonlinear solution, which results in longer solution times and a possibility that the solution will not converge. A common reason for nonconvergence is rigid body motion. If the solution fails to converge, running a Natural Frequency simulation of your setup may help determine if the contacts and supports are set up correctly. In the Refine stage setting the Adjust gap or overlap for frictionless or frictional contacts to Make just touching can be useful for overcoming nonconvergence due to rigid body motion.
Contact stress results on curved surfaces with frictionless contact may be inaccurate in the Explore stage depending on the geometry and solution fidelity. Use the Refine stage for improved stress results.
For kinematic assembly conditions, you can reduce solution time by using hinge or a spherical joints rather than frictionless or frictional contact.