Abstract

We analyse the sedimentation of circular disks bent into a U-shape and study how breaking one symmetry by pinching the disk along its axis changes the inertialess sedimentation dynamics. Numerical simulations and experiments show that fluttering is robust over a wide range of shapes, evolving toward helical paths, while sufficiently strong pinching leads to drifting without rotation. The work establishes criteria for the transition between these behaviours and discusses implications for dilute suspensions.

Abstract

We analyse the sedimentation of circular disks bent into a U-shape and study how breaking one symmetry by pinching the disk along its axis changes the inertialess sedimentation dynamics. Numerical simulations and experiments show that fluttering is robust over a wide range of shapes, evolving toward helical paths, while sufficiently strong pinching leads to drifting without rotation. The work establishes criteria for the transition between these behaviours and discusses implications for dilute suspensions.

Abstract

We analyse the sedimentation of circular disks bent into a U-shape and study how breaking one symmetry by pinching the disk along its axis changes the inertialess sedimentation dynamics. Numerical simulations and experiments show that fluttering is robust over a wide range of shapes, evolving toward helical paths, while sufficiently strong pinching leads to drifting without rotation. The work establishes criteria for the transition between these behaviours and discusses implications for dilute suspensions.

Abstract

We analyse the sedimentation of circular disks bent into a U-shape and study how breaking one symmetry by pinching the disk along its axis changes the inertialess sedimentation dynamics. Numerical simulations and experiments show that fluttering is robust over a wide range of shapes, evolving toward helical paths, while sufficiently strong pinching leads to drifting without rotation. The work establishes criteria for the transition between these behaviours and discusses implications for dilute suspensions.