*Article* **Settling of Mesoplastics in an Open-Channel Flow**

**Luka Kevorkijan 1, Elvis Žic 2, Luka Lešnik <sup>1</sup> and Ignacijo Biluš 1,\***


**Abstract:** Pollution of water by plastic contaminants has received increasing attention, owing to its negative effects on ecosystems. Small plastic particles propagate in water and can travel long distances from the source of pollution. In order to research the settling motion of particles in water flow, a small-scale experiment was conducted, whereby spherical plastic particles of varying diameters were released in an open-channel flow. Three approaches were investigated to numerically simulate the motion of particles. The numerical simulation results were compared and validated with experimental data. The presented methods allow for deeper insight into particle motion in fluid flow and could be extended to a larger scale to predict the propagation of mesoplastics in natural environments.

**Keywords:** dense discrete phase model; discrete element method; diameter; discrete phase model; mesoplastics; particle; settling
