Wall resolving large eddy simulation (LES) with the dynamic Smagorinsky model (DSM) is implemented under the single phase Euler-Euler framework to investigate the effects of suspending noncohesive sediment on the flow characteristics in a turbulent open channel flow.
Numerous laboratory-scale studies during the last few decades have focused on the understanding of the complex interactions between the suspended sediments and the carrier fluid. Several prominent issues may be present in this respect.
Wu et al. (2000) simulated the sediment transport in an 180° bend with a movable bend using the Reynolds-averaged Navier-Stokes (RANS) equations with the 푘 ε turbulence model and found out that it is needed to use a 3D model to capture a scour channel, bar and secondary flows. Lin and Falconer (2010) also emphasized on the use of a 3D layer integrated numerical modeling and the appropriate value of the Schmidt number when validating the suspended sediment concentration profile against the laboratory observation.
Toorman (2002) reported that the bed boundary condition and shear velocity are key concepts in the 2D numerical modeling of the turbulent flows with the cohesive suspended sediment particles. It was shown that the drag reduction occurred because of the buoyancy damping. Moreover, the 3D simulation was advised for the coastal and estuarine applications. Nino and Garcia (1996) experimentally examined the interactions between the sediment particles and the turbulence close to the wall in an open channel flow with the smooth and rough beds. While the coherent flow structures in the near-wall region were responsible for the entrainment of sediments into the suspension, the roughness on the wall had no effect.
Hsu et al. (2003) considered the dilute sediment transport in a 2D steady, uniform, open channel flow driven by the gravity. Using the two-phase approach, the damping of the fluid turbulence, the reduction of the Karman constant and the decrease of the mixing length were reported.