Large Large Eddy Simulation Model Development for Turbulent Dispersed Gas-Solid Flows

• Applicant: Professor Dr. Berend van Wachem, Ph.D.
• Subject Area: Fluid Mechanics ; Mechanical Process Engineering
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 457509672

While there are a number of validated turbulence models available for unconfined single-phase flows, much less work has been done for particle-laden flows. The influence of particles on the turbulence and the dispersion of particles due to turbulence play a significant role for the overall flow behaviour, but the physical phenomena are still largely unknown. Although the modelling framework of "Large Eddy Simulation" (LES) has had an enormous impact in single-phase flow modelling, such a framework is not yet sufficiently mature to accurately predict particle-laden flows. So far, the closures used to predict turbulent particle-laden flows are typically based upon single-phase ideas or simplified flow situations. Current LES models for particle-laden flows do not accurately account for the behaviour of the unresolved scales on the particles and do not accurately account for the effect of the particles on the turbulence.The current proposal aims to develop a LES model to accurately predict the complex behaviour of unconfined particle-laden turbulent flows. To achieve this, a number of scientifically fundamental questions will be addressed, such as how to accurately reconstruct the flow statistics from the unresolved scales, how to take into account the effect of the particles' behaviour on the behaviour of the turbulence, and how to accurately predict the wavenumbers at which modulation of the flow occurs. Such a novel two-phase coupled LES model will be developed from detailed studies of the interactions of particles and eddies by means of true direct numerical simulations. The novel framework will be scrutinised and validated with a number of challenging test-cases.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Fabien Evrard