Published:
[Erscheinungsort nicht ermittelbar]: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery, 2018
Published in:New Frontiers in Multiphase CFD for the 21st Century Energy Mix (18w5139) ; (Jan. 2018)
Extent:
1 Online-Ressource (77 MB, 00:22:25:07)
Language:
English
DOI:
10.5446/60533
Identifier:
Origination:
Footnote:
Audiovisuelles Material
Description:
Euler-Lagrange simulations of pointwise particles in turbulence have been widely employed for understanding the fundamental physics of dispersed flows. Most of the times, particles are modelled as isotropic and rigid. In this paper, we investigate the dynamics of elongated flexible particles in turbulent channel flow. We consider particles that are longer than the Kolmogorov length scale of the carrier flow, and their velocity relative to the surrounding fluid is non negligible. Such particles are modelled as chains of sub-Kolmogorov rigid rods connected through ball-and-socket joints that enable bending and twisting under the action of the local fluid velocity gradients. We examine the effect of local shear and turbulence anisotropy on the translational and rotational behaviour of the fibers, considering different elongation (parameterized by the aspect ratio) and inertia (parameterized by the Stokes number). Velocity, orientation and concentration statistics, extracted from one-way and two-way coupled direct numerical simulations, will be presented to give insights into the complex fiber-turbulence interactions that arise when non-sphericity and deformability add to inertial bias. The physical problem considered here provides a useful foundation for exploring the capability of the point-particle approach to capture the macroscopic features of multiphase flows of elongated deformable particles