A finite element scheme for colliding meshes [EM device modelling]

This paper describes a scheme which allows two separate finite element meshes to slide into and thus overlap each other. The Lagrange multipliers method is used to couple the two meshes together at their boundary. Overlapping elements are dealt with by adjusting the contributions of the elements of one of the two meshes to the system matrix according to the extent of overlap in such a way that at total overlap, those elements are effectively decoupled from the model. Applications include the modelling of electromagnetic plunger type devices.