An Embedded Mesh Approach for Isogeometric Boundary Layers in Contact Mechanics

TL;DR

This paper introduces a new discretization workflow for contact problems that separates the contact interface mesh from the bulk domain mesh, enabling tailored meshing strategies and improved geometric representation using NURBS-based boundary layers.

Contribution

It presents a novel embedded mesh approach combining NURBS boundary layers with structured Cartesian grids for contact mechanics, enhancing flexibility and accuracy.

Findings

Effective decoupling of contact interface and bulk meshes

Improved geometric smoothness and continuity at contact surfaces

Validated through numerical examples demonstrating accuracy

Abstract

This paper proposes a novel discretization workflow for contact problems in which the discretization of the contact interface is decoupled from that of the bulk domain. This separation enables independently tailored meshes for the contact interface and the bulk volume, allowing local requirements--such as element type and mesh resolution--to be addressed efficiently. Exploiting the boundary representation of CAD models, the contact interface of each body is discretized using a NURBS-based boundary layer mesh. This provides a smooth geometric description of the contact surface and enhanced inter-element continuity. The bulk domain is discretized using a structured Cartesian grid. To couple the resulting non-matching discretizations, an embedded mesh approach based on a mortar-type constraint formulation is employed. The paper describes in detail the proposed discretization workflow for generating both the isogeometric boundary layer and the structured Cartesian grid, and presents several strategies for constructing NURBS-based boundary layer meshes. Finally, a set of numerical examples is provided to validate the proposed approach.