A two-species continuum model for aeolian sand transport

TL;DR

This paper introduces a continuum model for aeolian sand transport that accurately captures both saltating and creeping grains, aligning well with experimental data and enabling diverse applications.

Contribution

It develops a novel two-species continuum model that improves upon mean-field approaches while maintaining computational efficiency.

Findings

Model predictions match wind tunnel experiments.

Accurately describes sand transport from onset to storm conditions.

Provides a foundation for studying dune formation and dust emission.

Abstract

Starting from the physics on the grain scale, we develop a simple continuum description of aeolian sand transport. Beyond popular mean-field models, but without sacrificing their computational efficiency, it accounts for both dominant grain populations, hopping (or "saltating") and creeping (or "reptating") grains. The predicted stationary sand transport rate is in excellent agreement with wind tunnel experiments simulating wind conditions ranging from the onset of saltation to storms. Our closed set of equations thus provides an analytically tractable, numerically precise, and computationally efficient starting point for applications addressing a wealth of phenomena from dune formation to dust emission.