ANSYS CONTACT PROBLEM
ANSYS CONTACT PROBLEM
(OP)
Hello,
I'm trying to simulate a compression test. My specimen is a cube and I'm trying to press it with a rigid surface but the surface moves through the specimen without imposing any deformation to it.
Is it possible to press a solid body with a surface or is there something wrong with my model?
Thank you in advance.
I'm trying to simulate a compression test. My specimen is a cube and I'm trying to press it with a rigid surface but the surface moves through the specimen without imposing any deformation to it.
Is it possible to press a solid body with a surface or is there something wrong with my model?
Thank you in advance.
NP





RE: ANSYS CONTACT PROBLEM
It might help to read ANSYS help on this topic:
Spoiler:
For general 3-D rigid surfaces, target segment elements can be defined by area meshing (AMESH). Set KEYOPT(1) = 0 (the default) to generate low order target elements (3-node triangles and/or 4-node quadrilaterals) for rigid surfaces. Set KEYOPT(1) = 1 to generate target elements with midside nodes (6-node triangles and/or 8-node quadrilaterals).
For 3-D rigid lines, target segment elements can be defined by line meshing (LMESH). Set KEYOPT(1) = 0 (the default) to generate low order target elements (2-node straight lines). Set KEYOPT(1) = 1 to generate target elements with midside nodes (3-node parabolas).
You can also use keypoint meshing (KMESH) to generate the pilot node.
If the TARGE170 elements will be created via program meshing (AMESH, LMESH, or KMESH commands), then the TSHAP command is ignored and ANSYS chooses the correct shape automatically.
For rigid-to-flexible contact, by default, ANSYS automatically fixes the structural degree of freedom for rigid target nodes if they aren't explicitly constrained (KEYOPT(2) = 0). If you wish, you can override the automatic boundary condition settings by setting KEYOPT(2) = 1 for the target elements. For flexible-to-flexible contact, no special boundary conditions treatment is performed, and the KEYOPT(2) = 0 setting should be used.
For each rigid-flexible contact pair, you can assign only one pilot node to an entire rigid target surface (or none if it is not needed). The pilot node, unlike the other segment types, is used to define the degrees of freedom for the entire target surface. This node can be any of the target surface nodes, but it does not have to be. All possible rigid motions of the target surface will be a combination of a translation and a rotation around the pilot node. The pilot node provides a convenient and powerful way to assign boundary conditions such as rotations, translations, moments, temperature, voltage, and magnetic potential on an entire rigid target surface. By default (KEYOPT(2) = 0), you can assign the boundary conditions only to the pilot node, eliminating the need to assign boundary conditions to individual target nodes, thus reducing the chance of errors. ANSYS will also automatically fix the structural degrees of freedom on the pilot node if they aren't explicitly constrained.
By setting KEYOPT(2) = 1 for the target elements, you can apply boundary conditions on any rigid target nodes rather than only on the pilot node. It is your responsibility to make sure the rigid target surface is not under-constrained or over-constrained. It is still recommended that you apply all boundary conditions on the pilot node, even when KEYOPT(2) = 1.