A Hyperbolic Moment Based Shallow Water Model for Coupled Bedload Suspended Load Morphodynamics with Variable Density

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Parvin, Afroja, Samaey, Giovanni, Koellermeier, Julian
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915942524518400
author Parvin, Afroja
Samaey, Giovanni
Koellermeier, Julian
author_facet Parvin, Afroja
Samaey, Giovanni
Koellermeier, Julian
contents In this paper, we develop the Hyperbolic Shallow Water Exner Moment model with Erosion and Deposition (HSWEMED), extending the shallow water moment framework to capture coupled morphodynamics with erosion and deposition. HSWEMED introduces a suspended-sediment concentration equation, couples concentration-dependent mixture density with the momentum and higher-order moment equations, and includes source terms due to erosion and deposition. Starting from the incompressible Navier-Stokes equations for a water-sediment mixture, we derive a coupled system consisting of the shallow water equations, moment equations for polynomial velocity coefficients, a depth-averaged suspended-sediment equation, and an Exner equation for bedload transport with erosion-deposition coupling. Although the transported scalar is depth-averaged, we reconstruct a low-order vertical concentration profile consistent with the moment representation of velocity, providing the near-bed concentration needed in the closure. We prove hyperbolicity through hyperbolic regularization and derive dissipative energy balance relations for lower-order models. Numerical results are obtained with a path-conservative finite-volume scheme based on a Lax-Friedrichs-type flux. Several dam-break tests, including wet/dry front cases, are validated against laboratory experiments, showing improved accuracy over existing shallow water moment models. The proposed HSWEMED provides a mathematically well-posed and computationally efficient framework for morphodynamic simulations.
format Preprint
id arxiv_https___arxiv_org_abs_2505_22278
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Hyperbolic Moment Based Shallow Water Model for Coupled Bedload Suspended Load Morphodynamics with Variable Density
Parvin, Afroja
Samaey, Giovanni
Koellermeier, Julian
Numerical Analysis
Geophysics
In this paper, we develop the Hyperbolic Shallow Water Exner Moment model with Erosion and Deposition (HSWEMED), extending the shallow water moment framework to capture coupled morphodynamics with erosion and deposition. HSWEMED introduces a suspended-sediment concentration equation, couples concentration-dependent mixture density with the momentum and higher-order moment equations, and includes source terms due to erosion and deposition. Starting from the incompressible Navier-Stokes equations for a water-sediment mixture, we derive a coupled system consisting of the shallow water equations, moment equations for polynomial velocity coefficients, a depth-averaged suspended-sediment equation, and an Exner equation for bedload transport with erosion-deposition coupling. Although the transported scalar is depth-averaged, we reconstruct a low-order vertical concentration profile consistent with the moment representation of velocity, providing the near-bed concentration needed in the closure. We prove hyperbolicity through hyperbolic regularization and derive dissipative energy balance relations for lower-order models. Numerical results are obtained with a path-conservative finite-volume scheme based on a Lax-Friedrichs-type flux. Several dam-break tests, including wet/dry front cases, are validated against laboratory experiments, showing improved accuracy over existing shallow water moment models. The proposed HSWEMED provides a mathematically well-posed and computationally efficient framework for morphodynamic simulations.
title A Hyperbolic Moment Based Shallow Water Model for Coupled Bedload Suspended Load Morphodynamics with Variable Density
topic Numerical Analysis
Geophysics
url https://arxiv.org/abs/2505.22278