[zahrae]

Hello everyone!
I am working on particle deposition, I first solved the steady flow until I get the converged results then disabled the flow equations, and finally activated the DPM model with the unsteady tracking.
I fixed the number of injected particles at 20160 (448 particles are injected per time step) and the stop time at 0.45 of the particles and I run two different calculations. One with a time step size of 0.01 and the other one with 0.001 and I found different results.

for the 0.01:
Escaped 17511
trapped 0
left 2649

for the 0.001:
Escaped 2971
trapped 0
left 17189

please can anyone help me to understand the origin of this difference? how did the time step size of the flow affect the particles? based on what exactly can we choose the time step size o our simulation?

Any help please I would be very grateful!!
Best regards.

[zahrae]

please any guidelines !!!!