Jun 26, 2026
A hands-on evening at the Dresdner Lange Nacht der Wissenschaften 2026
The Sediment Transport stand invited visitors of all ages to observe, question and experiment.
A Night of Curiosity and Discovery
On 26 June 2026, TU Dresden became a lively meeting place for people who wanted to experience research up close. At the Sediment Transport stand, families, children and science enthusiasts stepped into the role of researchers. Through four simple but striking demonstrations, the team made visible a process that shapes rivers, supports water treatment, loads engineering structures and influences environmental risks: the close coupling between moving water and the particles it carries.
The stand was designed as a conversation rather than a display. Visitors mixed, poured, pressed and watched water clear, or remain cloudy, while members of the Sediment Transport Group connected each observation to a physical mechanism.
Water Is Only Half the Story
Sediment transport is not governed by fluid motion alone. Surface charge, cohesion, friction, force chains and elasticity give particles their own microstructure. Together with the moving water, these interactions determine whether grains remain suspended, settle, aggregate, jam or transfer stress to a boundary.
Hands-on demonstrations turned particle-scale physics into an open conversation between researchers, children and adults.
Four Experiments, One Connected Story
Settling and flocculation
Sand cleared quickly, while fine sediment kept the water turbid. Adding a flocculant joined small particles into larger aggregates that settled faster, a direct link to water treatment.
Force chains in a silo
Chickpeas in a cylinder showed that grains do not load a container like a liquid. Their contacts redirect part of the vertical weight toward the walls, an effect relevant to silos and infrastructure.
Cornstarch in water
The mixture flowed under gentle motion but stiffened or jammed when forced rapidly. Under high stress, frictional contacts form a temporary network that carries stress like a solid.
Soft hydrogel grains
Deformable, low-friction particles rearranged very differently from sand or chickpeas, showing how elasticity and the rules at each contact change the behaviour of the whole mixture.
TPH group members mixing cornstarch and water
Science Shared Beyond the Laboratory
The most memorable result was not a single demonstration, but the exchange around it. Children tested ideas immediately … adults connected the observations to muddy rivers, drinking-water treatment and engineering structures. Questions moved naturally from everyday experience to particle-scale physics. By making the experiments open-ended and tactile, the team showed how researchers build understanding: observe carefully, change one interaction, compare the response and link small-scale mechanisms to large-scale consequences.
Stand coordination
Dr. Franco Tapia and Maria Löffler, with members of the Sediment Transport Group at the Chair of Transport Processes in Hydrosystems
Primary content source
Sediment Transport Stand – Monitor Briefing (2026). Photographs supplied by the Sediment Transport Group (Veronika Saiz, Alexander Metelkin). Event context: TU Dresden’s official 2026 event review.