CCS and Power Systems
Crosscutting Research - University Training and Research
Implementation and Refinement of a Comprehensive Model for Dense Granular Flows
Project No: FE0006932
This project will use a combination of continuum simulations for model validation and discrete particle simulations for model refinement. The first phase will be immediate implementation into Multiphase Flow with Interphase eXchanges (MFIX)—a general-purpose computer code developed at NETL—of a steady-shear, continuum rheological model for dense granular flows developed recently by the research group. The researchers will perform hopper, bin, and chute flow simulations using MFIX, with the results compared to literature data. While the continuum simulations of the first phase will employ a formulation of boundary conditions that already exists in MFIX, the second phase of this project will aim to develop and implement a more rigorous treatment of boundary effects. These will be investigated via simulations using discrete element method (DEM) implemented in the Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) developed by Sandia National Laboratories.
The simulations will focus on simple shear flows of identical mono-disperse spheres, and will be performed on both a traditional computer cluster as well as a specialized graphics machine, which offers significant increases in the size of the systems that can be simulated. During the final phase, the team will connect macroscopic and microscopic descriptions of the flow, thereby allowing for the construction of a more detailed constitutive model for the particle-phase stress. Each model refinement will be implemented into MFIX and validated by simulating various test cases that include chute and hopper flows as before, as well as simple and oscillatory shear in a Couette cell.