A novel methodology for data-driven reduced-order modeling of stiff ODE systems was developed. A combination of a reversible nonlinear mapping to a reduced-order space and a data-driven neural ordinary differential equation (ODE) model allows efficient training and inference upon complex and highly stiff systems (e.g., combustion chemical kinetics). By regularizing the reduced-order mapping with an estimate of local stiffness, the nonlinear autoencoder neural network model is optimized to learn the highest reconstruction accuracy stiffness-reduced compression of the full-order system. This combination of stiffness-reduced autoencoder and neural ODE models constitutes the proposed reduced-order neural ODE (RONODE) methodology. This method was then applied to both a plug flow reactor (PFR) and a continuous stirred tank reactor (CSTR) with a 53 species and 325 reaction propane-air combustion chemical mechanism (GRI 3.0 mechanism). The RONODE model attained a 1.9 × 10−4 root-mean-square (RMS) error with a computational speed-up factor of 3.1 on the PFR system, while on the less stiff CSTR system the method attained a 2.1 × 10−4 RMS error with a computational speed-up factor of 1.3.
|Original language||English (US)|
|Title of host publication||AIAA SciTech Forum 2022|
|Publisher||American Institute of Aeronautics and Astronautics Inc, AIAA|
|State||Published - 2022|
|Event||AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022 - San Diego, United States|
Duration: Jan 3 2022 → Jan 7 2022
|Name||AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022|
|Conference||AIAA Science and Technology Forum and Exposition, AIAA SciTech Forum 2022|
|Period||1/3/22 → 1/7/22|
Bibliographical noteFunding Information:
S. Yang gratefully acknowledges the faculty start-up funding from the University of Minnesota (UMN). H.E. Dikeman acknowledges the support from the UMN Undergraduate Research Opportunities Program (UROP). H. Zhang acknowledges the support from the 3M Science and Technology Doctoral Fellowship, UMII MnDRIVE Graduate Assistantship Award, and Frontera Computational Science Fellowship. The authors acknowledge the computing resources provided by the Minnesota Supercomputing Institute (MSI).
© 2022, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.