Weak information transfer between non-matching warped interfaces

We consider the information transfer between non-matching finite elementmeshes arising from domain decomposition. Dealing with complex three-dimensional geometries, especially in the case of computational mechanics and nonlinear contact problems, one can usually not achieve a decomposition of the global domain with mere planar interfaces in a sensible way. Thus, subdomains with warped interfaces emerge which, after an independent discretization, yield a geometrically non-conforming decomposition with small gaps and overlaps. In this paper, we employ a mortar approach and develop a method for the assembly of a discrete coupling operator providing a stable information transfer across such geometrically distinct warped interfaces.