Change search
ReferencesLink to record
Permanent link

Direct link
Simulation of finite-size fibers in turbulent channel flows
2014 (English)In: Physical Review E. Statistical, Nonlinear, and Soft Matter Physics, ISSN 1539-3755, E-ISSN 1550-2376, Vol. 89, no 1, 013006Article in journal (Refereed) PublishedText
Abstract [en]

The dynamical behavior of almost neutrally buoyant finite-size rigid fibers or rods in turbulent channel flow is studied by direct numerical simulations. The time evolution of the fiber orientation and translational and rotational motions in a statistically steady channel flow is obtained for three different fiber lengths. The turbulent flow is modeled by an entropy lattice Boltzmann method, and the interaction between fibers and carrier fluid is modeled through an external boundary force method. Direct contact and lubrication force models for fiber-fiber interactions and fiber-wall interaction are taken into account to allow for a full four-way interaction. The density ratio is chosen to mimic cellulose fibers in water. It is shown that the finite size leads to fiber-turbulence interactions that are significantly different from earlier reported results for point like particles (e.g., elongated ellipsoids smaller than the Kolmogorov scale). An effect that becomes increasingly accentuated with fiber length is an accumulation in high-speed regions near the wall, resulting in a mean fiber velocity that is higher than the mean fluid velocity. The simulation results indicate that the finite-size fibers tend to stay in the high-speed streaks due to collisions with the wall. In the central region of the channel, long fibers tend to align in the spanwise direction. Closer to the wall the long fibers instead tend to toward to a rotation in the shear plane, while very close to the wall they become predominantly aligned in the streamwise direction.

Place, publisher, year, edition, pages
2014. Vol. 89, no 1, 013006
Keyword [en]
Lattice-Boltzmann Method, Ellipsoidal Particles, Shear-Flow, Numerical-Simulation, Drag Reduction, Viscous-Fluid, Orientation, Motion
National Category
Applied Mechanics
URN: urn:nbn:se:sh:diva-30120DOI: 10.1103/PhysRevE.89.013006ISI: 000332160600013ScopusID: 2-s2.0-84894594301OAI: diva2:932395
Swedish Research Council, 2011-5355 2010-3938 2010-4147 2010-6965
Available from: 2014-04-04 Created: 2016-06-01 Last updated: 2016-06-01Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Do-Quang, MinhAmberg, GustavBrethouwer, GertJohansson, Arne V.
In the same journal
Physical Review E. Statistical, Nonlinear, and Soft Matter Physics
Applied Mechanics

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 17 hits
ReferencesLink to record
Permanent link

Direct link