Multiphase particle motion queries
 

Hi,

Some questions about modelling a dispersed solid phase (particles in Lagrangian frame) being transported with a moving fluid (Eulerian frame) that I cannot find the answers:

1. Are there any rules about mesh element sizes in relation to the distance a particle is expected to move in a single time step? Should mesh elements be sized so that (in general) a particle moves no more than 1 element distance per time step.

2. If a CFD code is cell-centred so the density, momentum values etc are stored at cell centres are particles treated as being at 1) any location in an element or 2) are they assumed to also be located at cell centres?

Thanks.