Location: Watershed Physical Processes Research
Title: Application of material point method and Mohr-Coulomb strain softening constitutive model in simulations of multiphase granular flowsAuthor
REBILLOUT, LUC - University Of Mississippi | |
OZEREN, YAVUZ - University Of Mississippi | |
Langendoen, Eddy | |
ALTINAKAR, MUSTAFA - University Of Mississippi |
Submitted to: Journal of Hydraulic Engineering
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/26/2023 Publication Date: 3/13/2024 Citation: Rebillout, L., Ozeren, Y., Langendoen, E.J., Altinakar, M. 2024. Application of material point method and Mohr-Coulomb strain softening constitutive model in simulations of multiphase granular flows. Journal of Hydraulic Engineering. 150(3). Article 04024008. https://doi.org/10.1061/JHEND8.HYENG-13736. DOI: https://doi.org/10.1061/JHEND8.HYENG-13736 Interpretive Summary: The movement of slurries from reservoirs is difficult to predict because of the complex flow behavior of the liquid-granular mixture. Knowing how quickly and where slurries propagate is important to emergency preparation in case of dam failures. In collaboration with researchers from the National Center for Computational Hydroscience and Engineering, University of Mississippi, ARS scientists at Oxford, MS, have developed improved algorithms for the open-source Anura3D computer model to simulate the complex rheology of slurries. The improved Anura3D model was tested against laboratory data of hyper-concentrated dam break flows. The new algorithms were able to capture complex features within the slurry flow such as vortical structures, progressive failures, and liquefaction. The ability of computer models, like Anura3D, to accurately characterize slurry flows is critical to hazard assessment and mitigation planning for dam safety. Technical Abstract: Sudden displacement of large volumes of liquid-granular mixtures in nature (dam-breaks, land slides, floods, etc.) are often reported to be the most deadly and destructive. The flow behavior of those mixtures is complex and depends on a large variety of parameters: e.g., the size distribution of the solid phase, pre-displacement packing conditions, the ratio of solid to liquid phase, and the geometry of the domain. Because of the multitude of parameters and the large displacements involved, the numerical modeling of these phenomena is complex. A two-phase double point Material Point Method formulation (2P-DP MPM) in Anura3D, a particle based continuum numerical method, was tested against two experimental cases. Model simulations showed that simple constitutive models such as Mohr-Coulomb (MC) with perfect plasticity can be sufficient to accurately model bulk granular flow behavior. However, with slightly different initial conditions, these flows can exhibit more complex features such as progressive block failures, which necessitates a more advanced solid constitutive model such as Mohr-Coulomb Strain Softening (MCSS). Further, other simulation parameters like wall friction boundary conditions and fluidization threshold are also crucial in these types of numerical simulations. The ability of such models to capture complex failure modes are critical to assess dam safety. |