Print Email Facebook Twitter Development of a numerical for dynamic depositioning of non-Newtonian slurries Title Development of a numerical for dynamic depositioning of non-Newtonian slurries Author Van Es, H.E. Contributor Van Rhee, C. (mentor) Talmon, A.M. (mentor) Winterwerp, J.C. (mentor) Sittoni, L. (mentor) Faculty Mechanical, Maritime and Materials Engineering Department Offshore and Dredging Engineering Programme Dredging Engineering Date 2017-03-29 Abstract This study aims to improve the predictive capabilities of flow pattern and depositional behaviour of non-Newtonian, high concentration sand and fines mixtures. The depositional behaviour influences the geometry of the deposit and the distribution of sand and fines particles, which in turn influence the strength and consolidation performance of the deposit. Ultimately this affects the area reclamation targets from the mining industry. In this study an existing numerical model, Delft3D (a three-dimensional, open source flow model from Deltares utilized world-wide in various hydrodynamic and sediment transport studies), is extended with the physics that describe non-Newtonian rheology and sand settling in shear flow. The rheology determines the yield stress and viscosity of a fluid. Shear induced sand settling occurs for fluids with a yield stress. Sand settles under shear whereas smaller particles stay suspended, producing segregation. Segregation leads to non-uniformity in deposit composition (e.g sand and fines dominated areas). Rheology and sand settling mutually interact, directly influencing deposition patterns. This study is a continuation of the work of [Hanssen, 2016], who included specific rheology and sand settling formulation in a one-dimensional version of Delft3D (i.e. 1DV). As part of this work, further verification of this one-dimensional model has been performed and the model has been extended to two-dimensional vertical (i.e. 2DV in a longitudinal cross section). The extended model has been tested in 2DV with deposition over a 400 meters slope. A sensitivity analysis is performed to consider the effect of different solid contents and rheological properties. The model is also tested on specific oil sand applications and data, such as tailings deposition down a beach, mutual interaction of tailings with different rheology or strength and a characterization of fines capture compared with data. This study proved that the extended version of Delft3D can simulate a 2DV non-Newtonian high density flow including sand settling. However there are still some physical processes where the model needs improvements or further research is needed, such as laminar-turbulence regime; transition to 3D and the motion of sand layers. Further model verification and development goes hands in hands with a good data set. Specifically important are flume/field tests with rheology data and its variation with time, especially for polymer added tailings, to verify the model. Subject slurriesnon-NewtonianDelft3Drheologyshear setting To reference this document use: http://resolver.tudelft.nl/uuid:af5d248b-2f27-42f5-9064-7abe7de94655 Part of collection Student theses Document type master thesis Rights (c) 2017 Es, H.E. van Files PDF Thesis Hugo (Public version).pdf 7.3 MB Close viewer /islandora/object/uuid:af5d248b-2f27-42f5-9064-7abe7de94655/datastream/OBJ/view