Validation and calibration of coupled porous-medium and free-flow problems using pore-scale resolved models

The correct choice of interface conditions and effective parameters for coupled macroscale free-flow and porous-medium models is crucial for a complete mathematical description of the problem under consideration and for accurate numerical simulation of applications. We consider single-fluid-phase systems described by the Stokes-Darcy model. Different sets of coupling conditions for this model are available. However, the choice of these conditions and effective model parameters is often arbitrary. We use large scale lattice Boltzmann simulations to validate coupling conditions by comparison of the macroscale simulations against pore-scale resolved models. We analyse two settings (lid driven cavity over a porous bed and infiltration problem) with different geometrical configurations (channelised and staggered distributions of solid grains) and different sets of interface conditions. Effective parameters for the macroscale models are computed numerically for each geometrical configuration. Numerical simulation results demonstrate the sensitivity of the coupled Stokes-Darcy problem to the location of the sharp fluid-porous interface, the effective model parameters and the interface conditions

Lattice Boltzmann Methods for Particulate Flows with Medical and Technical Applications

Particulate flows appear in numerous medical and technical applications. The main aim of this thesis is to contribute models and numerical schemes towards an accurate as well as efficient simulation of a huge number of arbitrarily shaped particles. We therefore develop holistic mesoscopic models and simulation approaches using the Lattice Boltzmann Method, that on massively parallel machines efficiently solve a variety of problems of particulate flows