Collision dynamics of two barchan dunes simulated by a simple model

TL;DR

This study uses a simple simulation model to analyze how two barchan dunes collide, revealing that collision outcomes depend on mass ratio and initial lateral distance, and introduces differential equations for 1D dune collisions.

Contribution

It presents a new simple simulation approach and differential equations to model barchan dune collisions, aligning with experimental observations.

Findings

Collision outcomes depend on mass ratio and lateral distance.

Simulated processes include coalescence, ejection, and reorganization.

Model aligns qualitatively with water tank experiments.

Abstract

The collision processes of two crescentic dunes called barchans are systematically studied using a simple computer simulation model. The simulated processes, coalescence, ejection and reorganization, qualitatively correspond to those observed in a water tank experiment. Moreover we found the realized types of collision depend both on the mass ratio and on the lateral distance between barchans under initial conditions. A simple set of differential equations to describe the collision of one-dimensional (1D) dunes is introduced.