Computational study of radial particle migration and stresslet distributions in particle-laden turbulent pipe flow

• Published in: The European physical journal. E, Soft matter and biological physics Vol. 41; no. 3; pp. 34 - 17
• Main Authors: Gupta, A., Clercx, H. J. H., Toschi, F.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 21.03.2018; Springer Nature B.V
• Subjects: Biological and Medical Physics; Biophysics; Complex Fluids and Microfluidics; Complex Systems; Computational fluid dynamics; Computer simulation; Concentration (composition); Condensed matter physics; Dilution; Energy dissipation; Fluid flow; Fluids and Structures: Multi-scale coupling and modeling; Industrial applications; Laminar flow; Mathematical models; Nanotechnology; Physics; Physics and Astronomy; Pipe flow; Pipes; Polymer Sciences; Regular Article; Reynolds number; Rheological properties; Rheology; Single-phase flow; Slip velocity; Soft and Granular Matter; Surfaces and Interfaces; Thin Films; Turbulence; Turbulent flow; Topical issue: Fluids and Structures: Multi-scale coupling and modeling
• ISSN: 1292-8941; 1292-895X; 2429-5299; 1292-895X
• DOI: 10.1140/epje/i2018-11638-3

. Particle-laden turbulent flows occur in a variety of industrial applications as well as in naturally occurring flows. While the numerical simulation of such flows has seen significant advances in recent years, it still remains a challenging problem. Many studies investigated the rheology of dense suspensions in laminar flows as well as the dynamics of point-particles in turbulence. Here we employ a fully-resolved numerical simulation based on a lattice Boltzmann scheme, to investigate turbulent flow with large neutrally buoyant particles in a pipe flow at low Reynolds number and in dilute regimes. The energy input is kept fixed resulting in a Reynolds number based on the friction velocity around 250. Two different particle radii were used giving a particle-pipe diameter ratio of 0.05 and 0.075. The number of particles is kept constant resulting in a volume fraction of 0.54% and 1.83%, respectively. We investigated Eulerian and Lagrangian statistics along with the stresslet exerted by the fluid on the spherical particles. It was observed that the high particle-to-fluid slip velocity close to the wall corresponds locally to events of high energy dissipation, which are not present in the single-phase flow. The migration of particles from the inner to the outer region of the pipe, the dependence of the stresslet on the particle radial positions and a proxy for the fragmentation rate of the particles computed using the stresslet have been investigated. Graphical abstract