arXiv Machine Learning By Hemanth Chandravamsi, Hangchuan Hu, Ponkrshnan Thiagarajan, Tamer A. Zaki

Feature-preserving Latent-EnKF for Data Assimilation of Flows with Shocks

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The paper introduces a feature‑preserving latent‑EnKF for data assimilation of flows with shocks, addressing the failure of traditional EnKF when discontinuities are present. By updating ensembles in a low‑dimensional latent space learned via a coordinate‑conditioned auto‑decoder, the method maintains near‑Gaussian statistics and coherent flow features, enabling shock translation through coordinate morphing rather than superposition. Experiments on Sod shock‑tube, Mach 2 shock‑cylinder, and immersed‑body shape‑inference problems show accurate shock recovery without spurious oscillations.

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arXiv Machine Learning
Jun 11

Neural ensemble Kalman filter: Data assimilation for compressible flows with shocks

arXiv:2602. 23461v2 Announce Type: replace-cross Abstract: Data assimilation (DA) for compressible flows with shocks is challenging because many classical DA methods generate spurious oscillations and nonphysical features near uncertain shocks.

By Xu-Hui Zhou, Lorenzo Beronilla, Michael K. Sleeman, Hangchuan Hu, Matthias Morzfeld, Andrew M. Stuart, Tamer A. Zaki
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By Zhang Jiang (University of Wisconsin-Madison), Marios Andreou (University of Wisconsin-Madison), Sebastian Reich (University of Potsdam), Nan Chen (University of Wisconsin-Madison)