CFD-DEM solution verification: Fixed-bed studies

• Published in: Powder technology Vol. 339; no. C; pp. 760 - 764
• Main Authors: Fullmer, William D., Musser, Jordan
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.11.2018; Elsevier BV; Elsevier
• Subjects: Cell size; CFD-DEM; Charged particles; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; Convergence; Discretization; Extrapolation; Filtration; Fluid dynamics; Mathematical models; MFiX; Normal distribution; Parameter uncertainty; Regression analysis; Solution verification; CFD-DEM; MFiX; Solution verification
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2018.08.044

Fixed (frozen) particle configurations are used to study CFD-DEM convergence behavior in the limit of infinite grid resolution. A filtering scheme based on solving a diffusion equation, i.e., a Gaussian kernel, is used to interpolate particle information to the continuum grid, free of cell size limitations. A regression method is used for Richardson extrapolation of the discrete solutions to the grid-free solution. The regression method is shown to predict accurate extrapolation curves in the presence of the observed oscillatory convergence behavior. The extrapolation curve is used to complete the solution verification process by quantifying the numerical uncertainty present in the calculations. Several numerical and model parameters are studied including the spatial discretization method, the kernel width and the mean drag law. A manageable level of discretization error is found with relative discretization errors generally <4%. [Display omitted] •Solution verification based on grid-refinement is considered for CFD-DEM•Fixed-bed particle arrays and a grid-independent Gaussian kernel are used•The pressure drop converges to a unique solution in the limit of infinite resolution•Regression-based Richardson extrapolation works well with oscillatory convergence•Discretization error of the fixed-beds studies is quite small, generally <4%