Modeling turbulent polydispersed multiphase flows in stirring tank reactors

Mixing of solids and liquids in extensively present in applications in the pharmaceutical , food, (bio-)chemical and process industries. Due to the complex nature of flows with multiple phases, the classic design approach of new industrial mixing applications is very expensive and time consuming. Because of these issues the industries have a high demand for multiphase numerical models to help in the design of new mixing processes. However, state-of-the art models still fail to deliver reliable and computationally affordable predictions.

This project aims at developing a model for turbulent polydispersed solid-liquid flows. The main novelty of this model is that both the evolution of the particle size-distribution and the particle velocity-distribution will be simulated. It is generally accepted that these two properties can heavily influence the complex behavior in solid-liquid mixing processes. Accounting for both will make the model applicable in a wide range of flow regimes and will come closer to a fully predictive model than any of the SOTA models. The main technique that will be used is the quadrature method of moments. This type of model has the advantage to work in an Eulerian framework, which allows for fast solution algorithms which are not affected by the number of particles. The model will be implemented into the open-source CFD software OpenFOAM and validated against experimental data on an pilot-scale stirring vessel.