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DOE OSTI · 3364513

Higher-order LaSDI: Reduced order modeling with multiple time derivatives

Abstract

Solving complex partial differential equations (PDEs) is essential across scientific disciplines but often requires numerical models that can be prohibitively expensive in time-sensitive applications. Reduced-order models (ROMs) address this challenge by exploiting low-dimensional structure to create fast approximations. The Latent Space Dynamics Identification (LaSDI) framework has demonstrated success in learning ROMs for parameterized PDE families, but remains limited to first-order systems. Here, in this paper, we propose Higher-Order LaSDI (HLaSDI), which extends the LaSDI framework to PDEs with arbitrary order of time derivatives. This generalization significantly expands the applicability of LaSDI-based methods to systems previously outside their scope, including hyperbolic PDEs. We demonstrate HLaSDI’s accuracy and efficiency on several linear and nonlinear benchmark problems.

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BibTeXRIS

Stephany, Robert [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000208136223), Anderson, William [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000271641345), Choi, Youngsoo [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)] (ORCID:0000000187977970). 2026-03-20. Higher-order LaSDI: Reduced order modeling with multiple time derivatives. https://doi.org/10.1016/j.cma.2026.118890

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