Particle-resolved simulation of antidunes in free-surface flows

The interaction of supercritical turbulent flows with granular sediment beds is challenging to study both experimentally and numerically; this task has hampered the advances in understanding antidunes, most characteristic bedform flows. This article presents first numerical attempt simulate upstream-migrating antidunes geometrically resolved particles a liquid-gas interface. Our simulations provide data at resolution higher than laboratory experiments, they can therefore new insights into mechanisms antidune migration contribute deeper underlying physics. To manage simulations' computational costs physical complexity, we employ cumulant lattice Boltzmann method conjunction discrete element for particle interactions, as well volume fluid scheme track deformable free surface fluid. By reproducing two flow configurations previous experiments (Pascal et al., Earth Surf. Proc. Land., vol. 46(9), 2021, 1750-1765), demonstrate that our approach robust accurately predicts antidunes' amplitude, wavelength, celerity. Furthermore, simulated wall-shear stress, key parameter governing transport, excellent agreement experimental measurements. highly motion from simulation open perspectives detailed studies morphodynamics shallow