Shell Thickness and Offset in Contact Detection

When you use contact detection, the app considers shell thicknesses and offsets only if you search using 2D mesh parts rather than geometry.

See Also
About Contact Detection
Using Contact Detection

When you search for contact interactions based on geometry supports (Detect interactions on: Geometry), shell thickness and offset are ignored with respect to the search tolerance (separation distance).

When you search for contact interactions based on mesh supports (Detect interactions on: Mesh), shell thickness and offset are considered when deciding whether a particular pair of 2D shells will be found by the contact search. In the figure below, T is the search tolerance, d1 is the actual distance between mesh parts P1 and P2, and d2 is the distance when the same parts are modeled with a 2D shell mesh. In this case the pair of parts will be found by the contact search as long as T is greater than or equal to d1 (but not necessarily d2).



In terms of the thicknesses t1 and t2, the contact search finds the pair of shell parts if

T⁢≥d2⁢⁢− (t1⁢+ t2⁢)2.

If the 2D shell mesh is not created exactly at the midsurface, the offset affects the contact search results. In the figure below, the pair of mesh parts is found by the contact search if the specified tolerance T is greater than the actual gap between the two plates.