This conference paper was submitted for presentation at the NAFEMS World Congress 2025, held in Salzburg, Austria from May 19–22, 2025.

Abstract

This work presents the application of the open-source finite element library FEniCSx to practical vibroacoustic problems, highlighting its potential for real-world engineering simulations. FEniCSx'™s flexibility, efficiency, and integration with high-performance computing frameworks such as MPI and PETSc make it a suitable choice for modeling coupled acoustic-structural systems. The focus is on demonstrating its capabilities in scenarios commonly encountered in industrial and research settings, including noise control, structural vibration, and sound propagation in complex domains. A key contribution of this study is the development and implementation of a monolithic coupling approach to address fluid-structure interaction problems with non-conformal meshes at the interface. This is achieved using a specially constructed interpolation matrix, enabling accurate and stable coupling of the fluid and structural fields without requiring mesh conformity. The approach maintains consistency in the exchange of variables across the interface while preserving computational efficiency and scalability, making it particularly well-suited for geometrically complex systems. The advantages and disadvantages of this method compared to the partitioned approach is described. The presentation also discusses the challenges and solutions associated with implementing Perfectly Matched Layers (PMLs) for absorbing boundary conditions, enforcing realistic boundary constraints, and optimizing solver configurations for the Helmholtz equation. The performance of direct and iterative solvers in handling large-scale vibroacoustic models is analyzed, providing practical guidance for their selection and configuration in FEniCSx. Case studies illustrate the application of these methods to realistic problems, emphasizing the adaptability and effectiveness of FEniCSx in addressing vibroacoustic challenges. The results demonstrate the framework's ability to deliver reliable and reproducible solutions while maintaining the transparency and cost-effectiveness of open-source tools. This work aims to provide a foundation for utilizing FEniCSx in vibroacoustics, offering insights into its strengths, limitations, and areas for further development. By bridging the gap between academic research and industrial applications, this study contributes to advancing the use of open-source software in vibroacoustic engineering.