Good morning,

I have two questions about my simulation; I would appreciate it if you could help me solve them.

1. Because my continuity equation does not converge, it did converge at the beginning, but after adding the particles, it stopped doing so. Should I reduce the timestep of the particles?

2. After many iterations, when my particles reached the top of the vertical pipe, some results it shows "reverse flow", why?
In my boundary conditions, I have placed that the pressure at the outlet is 0; also the velocity of the air in the inlet is 10m/s



Thank you in advance for taking the time to help me solve my doubts.