Non-linear disturbance growth during sedimentation in dilute fibre suspensions
2013 (English)In: Journal of Fluid Mechanics, ISSN 0022-1120, E-ISSN 1469-7645, Vol. 719, 268<-294 p.Article in journal (Refereed) Published
Disturbances in a dilute fibre suspension is studied with an Eulerian approach. Based on a linear stability analysis, it is shown that inertia and hydrodynamic diffusion damp perturbations at long wavelengths and short wavelengths, respectively, leading to a wavenumber selection. For small, but finite Reynolds number of the fluid bulk motion, the most unstable wavenumber is a finite value which increases with Reynolds number, and where the diffusion narrows the range of unstable wavenumbers. Numerical simulations of the full non-linear evolution in time of a normal mode perturbation show that the induced flow may either die or saturate on a finite amplitude. The character of this long time behaviour is dictated by the wavenumber and the presence or absence of the translational and rotational diffusivities.
Place, publisher, year, edition, pages
2013. Vol. 719, 268<-294 p.
particle/fluid flow, suspension, instability
IdentifiersURN: urn:nbn:se:kth:diva-98346DOI: 10.1017/jfm.2013.4ISI: 000315082000012ScopusID: 2-s2.0-84874238181OAI: oai:DiVA.org:kth-98346DiVA: diva2:536854
Updated from "Manuscript" to "Article". QC 201402072012-06-252012-06-252014-02-07Bibliographically approved