Clustering of particles in turbulence due to phoresis
File(s)
Published version
OA Location
Author(s)
Schmidt, L
Fouxon, I
Krug, D
van Reeuwijk, M
Holzner, M
Type
Journal Article
Abstract
We demonstrate that diffusiophoretic, thermophoretic, and chemotactic phenomena in turbulence lead to clustering of particles on multifractal sets that can be described using one single framework, valid when the particle size is much smaller than the smallest length scale of turbulence l0. To quantify the clustering, we derive positive pair correlations and fractal dimensions that hold for scales smaller than l0. For scales larger than l0 the pair-correlation function is predicted to show a stretched exponential decay towards 1. In the case of inhomogeneous turbulence we find that the fractal dimension depends on the direction of inhomogeneity. By performing experiments with particles in a turbulent gravity current we demonstrate clustering induced by salinity gradients in conformity to the theory. The particle size in the experiment is comparable to l0, outside the strict validity region of the theory, suggesting that the theoretical predictions transfer to this practically relevant regime. This clustering mechanism may provide the key to the understanding of a multitude of processes such as formation of marine snow in the ocean and population dynamics of chemotactic bacteria.
Date Issued
2016-06-20
Date Acceptance
2016-06-01
Citation
Physical Review E, 2016, 93 (6)
ISSN
1539-3755
Publisher
American Physical Society
Journal / Book Title
Physical Review E
Volume
93
Issue
6
Copyright Statement
© 2016 American Physical Society
Subjects
Science & Technology
Physical Sciences
Physics, Fluids & Plasmas
Physics, Mathematical
Physics
INERTIAL PARTICLES
HEAVY-PARTICLES
INTERMITTENT DISTRIBUTION
RANDOM FLOWS
AGGREGATION
THERMOPHORESIS
ACCELERATION
TEMPERATURE
STATISTICS
INITIATION
Fluids & Plasmas
01 Mathematical Sciences
02 Physical Sciences
09 Engineering
Publication Status
Published
Article Number
063110