An open-source ABAQUS implementation of the scaled boundary finite element method to study interfacial problems using polyhedral meshes

TL;DR

This paper presents an open-source implementation of the scaled boundary finite element method (SBFEM) in ABAQUS, enabling efficient analysis of interfacial problems with polyhedral meshes and complex geometries.

Contribution

The authors integrate SBFEM-based polyhedral elements into ABAQUS via user subroutines, enhancing its capability to handle non-matching interfaces and complex geometries.

Findings

Polyhedral elements improve interface treatment in finite element analysis.

The implementation simplifies meshing for complex geometries from digital images or STL files.

Numerical examples demonstrate the advantages of polyhedral elements in interfacial problems.

Abstract

The scaled boundary finite element method (SBFEM) is capable of generating polyhedral elements with an arbitrary number of surfaces. This salient feature significantly alleviates the meshing burden being a bottleneck in the analysis pipeline in the standard finite element method (FEM). In this paper, we implement polyhedral elements based on the SBFEM into the commercial finite element software ABAQUS. To this end, user elements are provided through the user subroutine UEL. Detailed explanations regarding the data structures and implementational aspects of the procedures are given. The focus of the current implementation is on interfacial problems and therefore, element-based surfaces are created on polyhedral user elements to establish interactions. This is achieved by an overlay of standard finite elements with negligible stiffness, provided in the ABAQUS element library, with polyhedral user elements. By means of several numerical examples, the advantages of polyhedral elements regarding the treatment of non-matching interfaces and automatic mesh generation are clearly demonstrated. Thus, the performance of ABAQUS for problems involving interfaces is augmented based on the availability of polyhedral meshes. Due to the implementation of polyhedral user elements, ABAQUS can directly handle complex geometries given in the form of digital images or stereolithography (STL) files. In order to facilitate the use of the proposed approach, the code of the UEL is published open-source and can be downloaded from https://github.com/ShukaiYa/SBFEM-UEL.