Experimental and DEM studies on the distribution of voidage in the random filling bed of ellipsoidal particles.

ABSTRACT The average voidage, radial voidage and axial voidage distribution in ellipsoidal pellets bed layer were studied by experiments and Discrete Element Method (DEM) Simulation. A series of experiments were used to determine the collision parameters of DEM model. The influence of the bed geometry factor on the average voidage and the radial voidage of the bed layer were investigated, the distribution of axial voidage in the bed was observed under different bed height conditions. The results show that the pellet diameter and cylinder diameter are the critical factor affecting the bed voidage distribution. With the bed geometry factor increasing, the average voidage of the bed gradually decreased. When D / d p > 50, the average voidage of the bed approaches to a constant (0.292). The damped oscillation of the radial voidage distributes from the wall toward the center of bed, and there is a maximum value near the wall. When the total height of the bed is constant, ignoring the influence of edge effect, the axial voidage increased gradually and eventually tends to be constant. With the gradual increase of the bed height, the change rate of the voidage and the axial voidage at the same height gradually decreased. Graphical abstract Unlabelled Image Highlights • The distribution of voidage in randomly packed beds with ellipsoidal particles were studied by experiments and DEM. • The linear relations were found between bed geometry factor and average voidage distribution. • The linear relations were found between bed height and axial voidage distribution. • The damped oscillation of the radial voidage distributed from the wall toward the center of bed. [ABSTRACT FROM AUTHOR]