Speaker
Description
The dynamics of non-spherical particles in turbulence are governed by the interplay between inertia and orientation-dependent hydrodynamic forces. We investigate rigid fibers dynamics by bridging two asymptotic descriptions: the small-size limit described by Jeffery’s equation, and the finite-length limit captured by slender-body theory. This framework enables systematic variation of aspect ratio, fiber length, and Stokes number. Using direct numerical simulations, we examine preferential alignment and small-scale clustering. At low Stokes numbers, fibers tend to align with the most unstable direction associated to the attractor towards which they converge and exhibit strong clustering consistent with convergence onto a fractal attractor. As the Stokes number increases, clustering is progressively reduced, with the attractor dimension approaching that of a uniform distribution, consistent with the expected behavior of inertial particles and the caustics mechanism.
This work was supported by the ANR through Project No. ANR-21-CE30-0040-01 and funded by the European Union’s Horizon Europe research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 101273291, project DragREACT. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Executive Agency (REA). Neither the European Union nor the European Research Executive Agency (REA) can be held responsible for them.