2D vs 3D model, Eulerian vs Particle tracking

Itchie

Hi CFD guys,

I'm modeling two-phase flow in a pipe. Are the results of 2D axisymmetric(x & y axis,1 element thick) and 3D simulations should be comparably the same for well converged solutions? If not can I conclude that the reason for the difference is that the values in the 3rd axis (e.g. z axis) are significant? Another thing, should I expect that the results of Eulerian-Eulerian and Particle tracking are comparably the same for accurate solutions? I don't know if these are non-sense questions but please help me.

Thanks guys! Itchie