Supporting data and methods for the multi-scale modelling of freeze-drying of microparticles in packed-beds

Abstract

A multi-scale approach can be used to simulate the drying behavior of microparticles in packed-bed. Data outcomes from discrete element method (DEM) and computational fluid dynamics (CFD) simulations can be used to estimate some relevant product characteristics, such as the porosity, tortuosity, voids in the bed and permeability which are required by the multi scale model. Data from DEM simulations are presented, with a particular focus on the influence of the model parameters, packing characteristics and inhomogeneities (wall effect and particles segregation); computational costs and scala bility are also considered. Data on the properties of packings as modeled at the macroscale are presented with regard to the thermal conductivity of gases in the Knudsen regime and effective properties of packed-beds modeled as a pseudo-homogeneous medium. A mathematical model of the freeze-drying of single microparticles and its outcomes are first presented. Data outcomes from the mathematical model at the macroscale concerning the drying behavior of microparticles in a tray and in a vial are then presented and can be used for process design. Some further data, with detailed interpretation and discussion of the presented data, can be found in the related research data article, “A multi-scale computational framework for modelling the freeze-drying of microparticles in packed-beds” (Capozzi et al., 2019).

High-Accuracy Simulations to Model Pyrometallurgical Processes in a Secondary Lead Reverberatory Furnace

“…Historically, the DEM model has been used in the simulation of molecular-scale dynamics and can provide otherwise impossible-to-measure detail on particle-wise values of temperature, velocity, and concentration, among other parameters. The DEM model is extensively used in the pharmaceutical industry, in drying applications [17], [18], and in seeded particulate flows, in which the volume fraction of particles is very low and yet has significant effects on the local flow field. With the DEM model, additional models for rolling resistance, artificial viscosity, particle-particle collisions, and particle-wall collisions provide valuable detail to pyrometallurgical applications for discerning injection effects on the burden in reverberatory furnaces.…”

Digital Twin for Lyophilization by Process Modeling in Manufacturing of Biologics

“…Here, the drying of spin-freezed vials by heat radiation or the drying of spray-freezed particles in vials should be mentioned [33,62]. Another focus for model based process design is the modeling of scale-up and batch uniformity [36,[63][64][65][66].…”

Microwave-Assisted Freeze-Drying with Frequency-Based Control Concepts via Solid-State Generators: A Simulative and Experimental Study

“…This results in a complex coupling of electromagnetic and thermodynamic processes. Whereas there are numerous studies dealing with the modeling of CFD, e.g., [7,31,32], there are only a few works on modeling MFD, e.g., [19][20][21]. In some of the latter, the assumption of a spatially homogeneous microwave field was made [20,21] to solve a thermodynamic model.…”