Figure 3 compares the particle distribution percentage from the inner wall (x/D=0.0) to the outer wall (x/D=1.0) at different locations in the vertical pipe. The particle distributions for the present CFD-DEM model and the traditional CFD-DEM model are remarkably consistent at different locations. It illustrates that the present CFD-DEM model has similar simulation applicability with the traditional one in dilute phase, and can be used to study dilute pneumatic conveying.