[Fluent.novice]

Hi there,

I am currently working on a project which involves introducing sand particles to a flow of water through a pipe. The objective is to understand if the particles are dropping or staying suspended in the fluid. The issue I am having is no matter how slow I make the water at the inlet, the sand particles never drop to the bottom of the pipe.

Some maybe useful information:
3D Model of Fluid Column
Transient
Multiphase: Eulerian
Phases: Water and Sand
Sand Phase: Granular and Granular Temp Model-Partial

Pipe Length: 10m
Inner Diameter: 0.25m
Sand Volume Fraction: 0.15
Water Velocity at inlet: 0.3m/s
Sand Velocity at inlet: 0.05m/s

I have been trying this with various changes to the settings and was advised to see if anyone here had any experience. Any help is very much appreciated, please let me know if you require any more information.

Thanks