Enhanced turbulent clustering of time-varying particles in random flow fields
Phys. Rev. E 114, 045104 – Published 21 October, 2026
DOI: https://doi.org/10.1103/kdm3-spck
Abstract
Particles suspended in turbulent flows tend to cluster within specific regions of the flow field. Previous research consistently reported that clustering is reduced at both very small and very large Stokes numbers for moderate Reynolds numbers. However, understanding how clustering evolves with varying Stokes numbers remains elusive. This work utilizes kinematic simulations to explore clustering of particles with varying inertia at high Reynolds numbers. Our results show that when the Stokes number varies over time, noticeable clusters form, even for low-Stokes-number particles that typically exhibit negligible clustering. This suggests that transient effects associated with evolving particle inertia can significantly enhance clustering behavior beyond what would be predicted based on a constant Stokes number alone. Our findings may suggest a different outlook on the enhanced clustering observed in many applications, including natural and atmospheric science, and cloud microphysics.
