Development of closure models for unresolved particle simulations of heat and mass transfer in dense particle beds using CPPPO: a library for fast parallel data filtering

Most multiphase flows are characterized by a wide range of length scales at which processes of interest take place. Hence, closure models need to be used to account for small-scale phenomena, e.g., heat transfer from the particle surface to the surrounding fluid. We present a new open-source library for data filtering and processing named CPPPO (Compilation of fluid-Particle Post-PrOcessing routines) that aims on developing such closure models. This library has been designed as a universal tool for developing closure models in the context of single- and multiphase flows. CPPPO features a novel, highly efficient algorithm for on-the-fly parallel data filtering, and can be easily connected to any existing flow simulator with a minimum amount of coding. Furthermore, we make an attempt to derive a closure model for heat and mass transfer (from DNS data) to be used in unresolved CFD-DEM simulations.