[akjha]

Hi,
1. What will be the primary phase in this three phase model with air water and sand?
2. How important is operating pressure location, Does it affect the simulation?
3. Does viscosity of granular phase matter when I am running an eulerian model?
4. Patching is required or not? If we patch can I patch the whole tank with water phase? Wont it contradict the concept that the continuous phase should be air if it is a primary phase.
5. What will be slip velocity specification for mass flow rate inlet BC? Is it the volume fraction or speed ratio of secondary phase with primary phase or is it between two secondary phases (water and sand)?
6. Equation of continuity is solved for only primary phase or for all phases because there is only one continuity residual appearing in the solution monitor.
7. Right now I am running the model in mixture mode, as suggested at many places in manuals and posts, and I will switch to eulerian after some time. What is the basis behind this?

I tried with primary phase as water (because sand is dispersed in water which is a continuous phase) and the top boundary which is practically open to atmosphere, as wall. Its giving some results but when I patch the pond partially with air it simply diverges. Pressure inlet or outlet at the top face is also not working. Please suggest me
1. what could be the top boundary condition?
2. Should I strictly go for air as primary phase?
3. And if I go for air as primary phase what should be the slip velocity specification in mass flow rate inlet BC, should I put volume fraction of sand and water phases in air?
Please guide me over this asap. If u need some additional info please do ask me.