[rmn_990]

Hi,
I am simulating fluid flow in a cylinder by injecting particles inside it from the inlet.
The boundary condition that I considered for the cylinder wall is trap. So the particles are supposed to attach to the cylinder wall or get out of the control volume from the outlet.

I did this simulation in transient mode but I don't know why the final data is different from steady-state in small time steps. When I do this transient simulation with DeltaT=1s, the result is similar to transient. but when I decrease the time step, the result will not be the same. In this case, the number of particles that attach to the cylinder wall will decrease as long as I decrease the time step.

I am doing these simulations in Ansys Fluent.