Numerical simulations of convection in porous media
High-resolution simulations are used to analyse the process of convection in porous media. In particular, the interplay of flow structure and mixing properties is considered. 2D and 3D numerical simulations with different boundary conditions are used to investigated the dissolution dynamics of Rayleigh-Darcy flow.
Experimental measurements of convection in porous media
Porous media flows are simulated with the aid of Hele-Shaw cells. The instability is controlled by the local density differences induced by solute gradients within the flow. Several boundary conditions have been considered, and new experimental methods to reconstruct the flow properties (solute concentration and fluid velocity) have been used and developed.
Experimental tracking of anisotropic particles in turbulent channel flow
High-speed imaging techniques are used to reconstruct and track anisotropic particles in turbulent channel flow. Experiments are performed in the TU Wien Turbulent Channel, a facility specifically designed to investigate the dynamics of fibres.
By providing visualisations of the spatial distribution of the virus copies, we highlight the high infection risk associated with droplets that remain airborne in the near proximity of an infected individual. The present study aims at raising awareness among public health authorities about this infection risk, which is grossly underestimated by current guidelines.