Higher-order dynamic mode decomposition on-the-fly: A low-order algorithm for complex fluid flows

Amor C, Schlatter P, Vinuesa R, Le Clainche S (2023)

Publication Type: Journal article

Publication year: 2023

Journal

Journal of Computational Physics Elsevier

Book Volume: 475

Article Number: 111849

DOI: 10.1016/j.jcp.2022.111849

Abstract

This article presents a new method to identify the main patterns describing the flow motion in complex flows. The algorithm is an extension of the higher-order dynamic mode decomposition (HODMD), which compresses the snapshots from the analysed database and progressively updates new compressed snapshots on-the-fly, so it is denoted as HODMD on-the-fly (HODMD-of). This algorithm can be applied in parallel to the numerical simulations (or experiments), and it exhibits two main advantages over offline algorithms: (i) it automatically selects on-the-fly the number of necessary snapshots from the database to identify the relevant dynamics; and (ii) it can be used from the beginning of a numerical simulation (or experiment), since it uses a sliding-window to automatically select, also on-the-fly, the suitable interval to perform the data analysis, i.e. it automatically identifies and discards the transient dynamics. The HODMD-of algorithm is suitable to build reduced order models, which have a much lower computational cost than the original simulation. The performance of the method has been tested in three different cases: the axi-symmetric synthetic jet, the three-dimensional wake of a circular cylinder and the turbulent wake behind a wall-mounted square cylinder. The obtained speed-up factors are around 7 with respect to HODMD; this value depends on the simulation and the configuration of the hyperparameters. HODMD-of also provides a significant reduction of the memory requirements, between 40−80% amongst the two- and three-dimensional cases studied in this paper.

Authors with CRIS profile

Philipp Schlatter

Involved external institutions

Okinawa Institute of Science and Technology (OIST) / 沖縄科学技術大学院大学 JP Japan (JP) Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH) SE Sweden (SE) Universidad Politécnica de Madrid (UPM) ES Spain (ES)

How to cite

APA:

Amor, C., Schlatter, P., Vinuesa, R., & Le Clainche, S. (2023). Higher-order dynamic mode decomposition on-the-fly: A low-order algorithm for complex fluid flows. Journal of Computational Physics, 475. https://dx.doi.org/10.1016/j.jcp.2022.111849

MLA:

Amor, Christian, et al. "Higher-order dynamic mode decomposition on-the-fly: A low-order algorithm for complex fluid flows." Journal of Computational Physics 475 (2023).

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