Dusting and Aeolian Transport

Nicholas Wood

Hey, I was wondering if anyoen could help me with modelling saltation and dusting in Fluent. I have been trying to replicate certain wind tunnel experiments (as done by Bagnold, Shao etc.) that involve a rectangular wind tunnel with a bed of sand and dust with and a velocity inlet at one end. I'm trying to measure the amount of dust being picked up and suspended in the tunnel due to turbulent forces and saltation of larger sand grains.

I've been trying to use the Eulerian model in an unsteady state with the k-e turbulence model usually with 2 or 3 phases but it never converges and is often unstable. The turbulent viscoisty is also always beign limited. I have used the DPM model also.

1. Does anyone know how to stabilize the Eulerian model in such a situation, can it even be used in this way?

2. Does anyone know how to create a UDF for the boundary condition of 'saltation' in the DPM model? I know it requires that momentum be transferred to the wall.

Thanks, Ive tried all the manual solutions and they have not worked, so I'd really appreciate the help.