Author(s): Rufus E. Dickinson; Kazumasa Matsumoto; Timothy I. Marjoribanks; Michio Sanjou; Christopher J. Keylock; Takaaki Okamoto

Linked Author(s): Michio Sanjou, Tim Marjoribanks, Chris Keylock

Keywords: Foliated Flow; Flexible Reconfiguration; Particle Image Velocimetry; Physical Theory

Abstract: For many types of flexible vegetation which block waterways, collect sediment, and provide shelter to fauna, foliage, rather than stems and branches, is the main source of plant surface area that has the potential to disrupt flow. Despite the variation in leaf flexibility across species, and the prevalent theory of flow-induced reconfiguration for plant stems, there is an imbalance in understanding regarding leaves and foliage, focusing on simple quantification of foliage density rather than flexibility. Seeking to correct this, we apply a recently developed theoretical perspective on leafy stems to experimentally study their behaviour in submerged patches spanning an open channel flow. We vary the ratio of leaf-to-stem flexibility, and control for vegetation density, testing over a range of flow velocities. Our results from Particle Image Velocimetry show differences in time and depth-averaged velocity and turbulent kinetic energy in the near and intermediate wake, suggesting that the applied theoretical perspective should be used to modulate understanding of foliage density.

DOI: https://doi.org/10.64697/iahr.proc.ise2026.abs.131

Year: 2026