Mary Ann Clarke, Jordan Musser, "The MFiX Particle-in-Cell Method (MFiXPIC) Theory Guide", DOE/NETL-2020/2115, NETL Technical Report Series; U.S. Department of Energy, National Energy Technology Laboratory: Morgantown, WV, 2020; p. 28. DOI: 10.2172/1630414.
Abstract: MFiX (Multiphase Flow with Interphase eXchanges) is an open-source multiphase flow solver developed at the National Energy Technology Laboratory. Within the code, users have access to a single phase or interpenetrating continua-based multiphase two-fluid model (TFM), a discrete element model (DEM), and a particle-in-cell model (PIC). TFM, DEM, and PIC can all be used to create multiphase simulations that include hydrodynamics, chemical reactions, and heat transfer. This document presents the underlying theory for the MFiX-PIC model only. MFiX-PIC is a Lagrangian solids model that tracks the position and trajectory of computational parcels that represent groups of identical spherical particles within a Eulerian fluid. It is firmly coupled to the fluid flow solver previously described in Musser and Carney (2020) and imitates many of the same Lagrangian methods described in Boyalakuntla (2003, 2006) and Garg et al. (2012). Evolving from 1-dimensional (Andrews and O’Rourke, 1996) and 2-dimensional (Snider et al., 1997) implementations, the current 3-dimensional PIC formulation most resembles the work of Snider (2001). MFiX-PIC is best suited for industrial-scale, semi-dense multiphase flow simulations where trend is more important than exactness of solution. The methodology utilizes statistical averaging techniques to advance simulations quickly and carries minimal particle-level overhead. Note that solutions do appear very realistic, and verification and validation studies confirm that the methodology predicts accurate flow characteristics (Vaidheeswaran et al., 2020). This document follows the notation and variable formats used in equations set forth in Musser and Carney (2020). It is suggested that the active reader, truly trying to digest MFiX-PIC theory, use this document in determined cooperation with Musser and Carney (2020) and Snider (2001).
Keywords: MFiX, Particle in Cell