High-performance coupled surface-subsurface flow simulation with SERGHEI-SWE-RE

Zheng, Na ; Li, Zhi ; Rickert, Gregor ; Morales-Hernández, Mario (Universidad de Zaragoza) ; Özgen-Xian, Ilhan ; Caviedes-Voullième, Daniel

Resumen: This work presents SERGHEI-SWE-RE, a performance-portable, parallel model that couples a fully dynamic two-dimensional Shallow Water Equation (SWE) solver with a three-dimensional Richards Equation (RE) solver within the Kokkos framework to simulate surface–subsurface flow exchange. The model features a modular architecture with sequential coupling strategy, supporting both synchronous and asynchronous executions of surface and subsurface modules. The SERGHEI-SWE-RE model is validated against five benchmark problems incorporating stationary and fluctuating free-surface tests, a tilted v-catchment, a lateral-flow slope without ponding, and a heterogeneous superslab. The results demonstrate good agreement with established models. Asynchronous coupling reduces wall-clock time by up to about 75 % in the superslab case while preserving simulation accuracy. Strong and weak scaling tests on multiple Intel Xeon CPUs and NVIDIA GPUs reveal robust portability, with near-ideal RE scaling and less-satisfactory SWE scaling at high GPU counts, suggesting future improvements on differentiated meshes or more advanced domain decomposition strategies. Overall, the results presented establish SERGHEI-SWE-RE as an efficient, flexible and scalable model for integrated surface-subsurface flow simulations.

Idioma: Inglés

DOI: 10.5194/gmd-19-2799-2026

Año: 2026

Publicado en: GEOSCIENTIFIC MODEL DEVELOPMENT 19, 7 (2026), 2799-2819
ISSN: 1991-959X

Tipo y forma: Article (Published version)

Área (Departamento): Área Mecánica de Fluidos (Dpto. Ciencia Tecnol.Mater.Fl.)