This thesis presents a comprehensive numerical study of the granular segregation in piling processes and vibrated systems. The research is carried with the help of a DEM model developed for ellipsoids. The simulation studies and associated analysis have elevated the triggering mechanisms of the segregation behavior to a new level where the observed segregation can be interpreted in both microscopic and macroscopic views. Furthermore, the adoption of ellipsoids largely demonstrates the effects of particle shape which significantly shortens the distance between scientific researches and real industrial issues.