Projection-based reduced order modeling of an iterative scheme for linear thermo-poroelasticity
Francesco Ballarin, Sanghyun Lee, Son-Young Yi
TL;DR
We address the computational challenge of linear thermo-poroelasticity by coupling a fixed-stress iterative scheme with projection-based ROMs trained from high-fidelity data. The offline stage uses a fixed-stress high-fidelity solver and POD to build reduced bases, while the online stage performs Galerkin projection for both monolithic (M-ROM) and fixed-stress (FS-ROM) formulations. The paper proves convergence of FS-HF to the monolithic HF solution and demonstrates FS-ROM convergence to FS-HF, achieving over two orders of magnitude speedups and effectively handling parametric heterogeneities. This approach enables fast, repeated simulations and multi-query analyses for THM systems with potential applications in geothermal and environmental settings.
Abstract
This paper explores an iterative coupling approach to solve linear thermo-poroelasticity problems, with its application as a high-fidelity discretization utilizing finite elements during the training of projection-based reduced order models. One of the main challenges in addressing coupled multi-physics problems is the complexity and computational expenses involved. In this study, we introduce a decoupled iterative solution approach, integrated with reduced order modeling, aimed at augmenting the efficiency of the computational algorithm. The iterative coupling technique we employ builds upon the established fixed-stress splitting scheme that has been extensively investigated for Biot's poroelasticity. By leveraging solutions derived from this coupled iterative scheme, the reduced order model employs an additional Galerkin projection onto a reduced basis space formed by a small number of modes obtained through proper orthogonal decomposition. The effectiveness of the proposed algorithm is demonstrated through numerical experiments, showcasing its computational prowess.
