The purpose of this study is to investigate the influence of design parameters for the scale-up of the depleted uranium (DU) bed. The actual DU bed chosen for this study has a DU loading of 1.86 kg for a tritium capacity of 70 g and is cylindrical in shape and equipped with copper foam to enhance internal heat transfer. Based on the reference DU bed geometry, three different scale-up bed geometries to increase the amount of DU loading up to 9.3 kg were designed under different aspect ratios for comparison purposes and simulated using a three-dimensional transient DU hydride model developed in our previous studies. The simulation results are compared in terms of the evolution of the DU hydride temperature and H/U atomic ratio during the DU hydriding process. This study helps to identify key design parameters (e.g., it is critical to scale up the DU bed geometry).