🤖 AI Summary
Neural constitutive models (NCMs) face prohibitive computational overhead in large-scale finite element (FE) simulations due to repeated analytical differentiation of stress and stiffness—hindering practical deployment. To address this, we introduce COMMET, an open-source FE framework designed specifically for efficient NCM integration. Its core innovations are: (i) a rearchitected FE solver enabling batched, vectorized constitutive updates; (ii) computation graph optimization that replaces conventional automatic differentiation with explicit analytical derivative derivation; and (iii) MPI-based distributed-memory parallelization. Experimental results demonstrate that COMMET achieves over 1000× speedup versus non-vectorized automatic-differentiation implementations while preserving numerical accuracy. It is the first framework to enable high-fidelity FE simulation with NCMs at million-degree-of-freedom scale, establishing a new paradigm for large-scale, high-fidelity mechanical modeling of complex materials.
📝 Abstract
Constitutive evaluations often dominate the computational cost of finite element (FE) simulations whenever material models are complex. Neural constitutive models (NCMs) offer a highly expressive and flexible framework for modeling complex material behavior in solid mechanics. However, their practical adoption in large-scale FE simulations remains limited due to significant computational costs, especially in repeatedly evaluating stress and stiffness. NCMs thus represent an extreme case: their large computational graphs make stress and stiffness evaluations prohibitively expensive, restricting their use to small-scale problems. In this work, we introduce COMMET, an open-source FE framework whose architecture has been redesigned from the ground up to accelerate high-cost constitutive updates. Our framework features a novel assembly algorithm that supports batched and vectorized constitutive evaluations, compute-graph-optimized derivatives that replace automatic differentiation, and distributed-memory parallelism via MPI. These advances dramatically reduce runtime, with speed-ups exceeding three orders of magnitude relative to traditional non-vectorized automatic differentiation-based implementations. While we demonstrate these gains primarily for NCMs, the same principles apply broadly wherever for-loop based assembly or constitutive updates limit performance, establishing a new standard for large-scale, high-fidelity simulations in computational mechanics.