I am a Phd student studying the flow of soil using CFD techniques and was wondering if there is anyone out there who can help me. I have studied vast amounts of literature into granular flow and the like and bulk flow is something that it appears has not been studied in any great depth. Granular flow is generally simulated using discrete particle simulations and therefore is computationally inefficient and in my case totaly unsuitable. I have found one or two papers on bulk flow (e.g. G Tardos in powder technology 1997 vol 92) but would like to know if there is any more or if anyone out there has any experience. Any help anyone can give me or any ideas they have on inforamtion sources, methods etc etc will be fantastic.

Sorry me again, just as an aside the way i am going to model this looks as though i will need to do some fiddling about with the viscous terms, i.e changing to non-linear viscosity or some such. Any ideas on which CFD code is likely to cope with this best?

Joel,

A lot of work has been and is being done on similar topics at the University of Glasgow under the supervision of Nenad Bicanic. Nenad is working on subjects such as flow in silos, particle infiltration and segregation due to size, airfoil flows, fluid-rock interaction and crack formation in rocks (looking at crack propagation in rock and granular soild modelling both fluids and solid/rock using some elaborate form of DEM). One of his students is still working on that for the petroleum industry I believe.

I am also aware of people using SPH (Smooth particle Hydrodynamics coming from Astrophysics) to model free surface problems. I was at a meeting in France at EDF-Chatou about a year ago and show a demo of a free surface calculation using this method.

I believe there are formulations for these parameters in the literature (I know I've heard about such formulation at Glasgow) because the link btw particulate matter and continuous fluid is not straighforward... Here again try and contact them. That wasn't my filed so I only "know" about it, and what I know is not much.