SCAIM Seminar: Anthony Wachs

Particle-laden flows are ubiquitous in environmental, geophysical and engineering processes. The intricate dynamics of these two-phase flows is governed by the momentum, heat and mass transfer between the continuous fluid phase and the dispersed particulate phase. While some multi-phase processes may be successfully modelled at the continuum scale through closure approximations, an increasing number of applications require resolution across scales, e.g. dense suspensions, fluidized beds. Within a multi-scale micro/meso/macro-framework, we develop robust numerical models at the micro and meso-scales, that both account for hydrodynamic interactions and particle/particle collisions. We present the mathematical issues related to modelling this type of flows together with the main numerical and computational features of our own simulation methods. Serial computations are almost not an option anymore and highly scalable codes on the most recent supercomputer architectures have become mandatory. We illustrate what can be gained from massively parallel computations in terms of physical insight into both fundamental questions and applications (essentially from the chemical engineering and process industry). We shortly discuss the next steps in the development of advanced numerical methods for particle-laden flows. Finally, we explain how knowledge gained at the micro scale can cascade upwards and contribute to the development of enhanced meso and macro-scale models.