Initial conditions in sedimentation tank
 

Dear members of forum,


I’m modeling a simple secondary sedimentation tank where particles settle onto the bottom of a tank. I’ve defined the problem as a particle transport solid option and water as a continuous fluid. Before running, I’ve consider two issues about initial conditions, here my doubt:


1. * Should I run the problem firstly only with continuous fluid until it would converge and after introduce the particles?


2. * How can I define initial conditions in order to perform that before entering the first particles, old particles are previously in the tank?



Thanks, any information could help me
Regards