The mechanism of sedimentation and large-strain consolidation is well-known to occur in oil-sand tailings. The transition point between the processes remains ambiguous and subjects to continued research. Sedimentation has been generally considered to follow Kynch’s theory however there are additional questions as to how closely the sedimentation follows theory. Recent studies undertaken by SoilVision Systems Ltd. and a client have endeavored to model sedimentation theory at a basic particulate level making use of combined Discrete Element Method (DEM) and Computational Fluid Dynamics (CFD). The purpose of this study is trying to match simulation results to both theoretical and experimental results. Therefore two types of models are currently used: the model using pure spherical particles (sphere model) and a model using cylindrical clumps (clump model). The sphere model will be used to verify simulation results with Kynch’s theory and the clump model will be used to simulate the sedimentation process of oil-sand tailings at a laboratory scale. The simulation procedures and the final results show that coupled DEM-CFD method can agree well with theoretical results and can also provide prediction for experimental results via calibration..