solid-fluid multiphase,please guide
 

I m trying to model dust and air flow.If I use
1) Eulerian: its taking too much time. how can I reduce time?
2) mixture is producing seperated surfaces. how can I make them granular?
3)VOF through user guide does nt seem appropriate. is it appropriate?

please guide me. need assistance

Residuals
 

I would suggest that you:

1. Try changing the under-relaxation factors and residual values if you need to decrease the clock time of each time step/iteration.

2. Use a better machine if possible.

Eulerian model is the best for your case.