(151b) DEM Simulations of Tablet Motion In a Vibratory Coating Pan

The motion of true biconvex tablet shapes in a vibratory continuous coater is studied using the Discrete Element Method (DEM). In contrast to rotating drums, motion is imparted to the tablets using vibrations about a pivot point offset from the center of the drum. A significant advantage of this approach is that the coater can be open from the top allowing for easy monitoring of the coating operation. A regime map identifying the range of amplitudes and frequency of vibrations required to create a tumbling motion of tablets inside the drum is obtained. It was found that for Froude numbers (Fr, based on the vibration frequency and amplitude at the drum center) greater than one, tumbling motion was achieved in the drum. For Fr slightly less than one, very slow tumbling motion occurs while for smaller Fr no motion was observed. The axial and transverse mixing of tablets was also studied for various values of Fr.