Three positions are available in the “OpaqueFlows” project, funded by an ERC Consolidator grant. This project unveils dense two-phase flows. These flows consist of a fluid containing suspended particles or droplets; examples include blood, milk, and slurries. While these flows are abundant in nature and industry, they are currently poorly understood and difficult to model. This is due to the fact that these flows are opaque, and current optical measurement techniques cannot see through them; very little experimental data is therefore available.