Computational investigations of solid–liquid particle interaction in a two-phase flow around a ducted obstruction

Abstract

The effect of bed obstruction on the dispersion of solid particles in a two-phase flow was numerically investigated. An algebraic slip mixture model was used to model this flow and the re-normalization group k-ϵ model to resolve flow turbulence. Computations were performed for three different sizes of solid particles to investigate their effect on turbulence modulation. Due to the obstruction, a distortion of the self-similar mean velocity profile was observed including the typical stratified dispersion of solid particles in the region comprising the stagnation and wake regions. Its length increases with particle size. The stagnation region is characterized by high preferential deposition of particles, whereas the wake region has a low concentration gradient. The effect of wake vortices on particle dispersion decreases as the particle size increases. Turbulence intensity increases with the particle size, whereas relative turbulence modulation was observed in complex flow regions for larger-sized particles.

Keywords:

• Algebraic slip mixture model
• particle size
• sediment transport
• turbulence
• two-phase flow