Learning Pore-scale Multiphase Flow from 4D Velocimetry

Chunyang Wang; Linqi Zhu; Yuxuan Gu; Robert van der Merwe; Xin Ju; Catherine Spurin; Samuel Krevor; Rex Ying; Tobias Pfaff; Martin J. Blunt; Tom Bultreys; Gege Wen

arXiv · 2603.12516

Learning Pore-scale Multiphase Flow from 4D Velocimetry

Chunyang Wang·Linqi Zhu·Yuxuan Gu·Robert van der Merwe·Xin Ju·Catherine Spurin·Samuel Krevor·Rex Ying·Tobias Pfaff·Martin J. Blunt·Tom Bultreys·Gege Wen

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Abstract

Multiphase flow in porous media underpins subsurface energy and environmental technologies, including geological CO$_2$ storage and underground hydrogen storage, yet pore-scale dynamics in realistic three-dimensional materials remain difficult to characterize and predict. Here we introduce a multimodal learning framework that infers multiphase pore-scale flow directly from time-resolved four-dimensional (4D) micro-velocimetry measurements. The model couples a graph network simulator for Lagrangian tracer-particle motion with a 3D U-Net for voxelized interface evolution. The imaged pore geometry serves as a boundary constraint to the flow velocity and the multiphase interface predictions, which are coupled and updated iteratively at each time step. Trained autoregressively on experimental sequences in capillary-dominated conditions ($Ca\approx10^{-6}$), the learned surrogate captures transient, nonlocal flow perturbations and abrupt interface rearrangements (Haines jumps) over rollouts spanning seconds of physical time, while reducing hour-to-day--scale direct numerical simulations to seconds of inference. By providing rapid, experimentally informed predictions, the framework opens a route to ''digital experiments'' to replicate pore-scale physics observed in multiphase flow experiments, offering an efficient tool for exploring injection conditions and pore-geometry effects relevant to subsurface carbon and hydrogen storage.

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Chunyang Wang, Linqi Zhu, Yuxuan Gu, Robert van der Merwe, Xin Ju, Catherine Spurin, Samuel Krevor, Rex Ying, Tobias Pfaff, Martin J. Blunt, Tom Bultreys, Gege Wen. 2026-03-12. Learning Pore-scale Multiphase Flow from 4D Velocimetry. https://arxiv.org/abs/2603.12516

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