This work deals with numerical simulation and experimental validation of cohesive and cohesionless granular material. In the first chapter a review of the die filling process, which is the motivation of this work, is described. Also a review on the main aspects of cohesion in granular media and material flow under variable gravitational force conditions is given. The second chapter describes the Discrete Element Method (DEM), methodology chosen in this work to simulate granular materials. Also the Coarse Graining Model (CGM), a modelling technique to describe the behaviour of fine particles by simulating coarser particles, is described from literature and our contributions for contact and cohesion models are added to the method. Chapter 3 describes a series of experiments used for DEM calibration, which are necessary to obtain physically correct results, such as angle of repose, shear cell and static angle. Furthermore, an experiment that mimics die filling process codenamed "Sandy", and a centrifuge used to analyze cohesion and cohesionless material flow under increased gravitational force conditions, are described along with their respective obtained data. Chapter 4 describes numerical simulations performed to calibrate our DEM model and validation through comparison of simulations to experiments performed with "Sandy". Material flow through a hopper is simulated and data is compared to experimental results. Finally, Chapter 5 describes a real size industrial application using DEM model calibrated for the very cohesive Molybdenum powder. Multiple shaking modes are applied to the die and their effect on the final density distribution is analyzed.