Related Experiment Video
Updated: Aug 18, 2026

The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Flow through Bottlenecks: Stronger Is Slower
Marta Grasa1, Laciel Alonso-Llanes1, Angel Garcimartín1
1Universidad de Navarra, Departamento de Física y Matemática Aplicada, Facultad de Ciencias, 31080 Pamplona, Spain.
None:
We present experimental results of the flow of programmable robots through a bottleneck. With these agents, velocity and force can be decoupled-a unique feature allowing us to show that, in the absence of physical contact and pushing from behind, and despite the development of clogs, moving faster always improves the flow of discrete systems through bottlenecks. Conversely, the flow is reduced if the robots are allowed to push. This result indicates that the pressure build-up within the system is a necessary condition to observe the effect previously known as faster-is-slower, a generic phenomenon emerging in a variety of discrete systems flowing through a narrowing which we argue should rather be called stronger-is-slower.
More Related Videos
Related Concept Videos
Blood Flow
Poiseuille's Law and Reynolds Number
General Characteristics of Pipe Flow II
The distance to reach a fully developed flow is called the entrance length and depends on the flow...
Steady, Laminar Flow Between Parallel Plates
Laminar Flow
Bernoulli's Equation

