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Article

Numerical simulations of the sedimentation in dilute fibre suspensions

Authors: Zhang, F.Z., Sardina, G.S., Dahlkild, A. A., Lundell, F., Brandt, L.B.
Document Type: Conference
Pubstate: Published
Journal: 8th International Conference on Multiphase Flow (ICMF), Jeju, Korea (2013)
Volume:   
Year: 2013

Abstract

Numerical simulations are used to investigate the density instability and the microstructure in dilute sedimenting fibre suspensions at non-zero Reynolds number. An efficient method based on a point-particle appro ximation is adopted to simulate large scale fibre suspensions with periodic boundary conditions. The density instability is captured in the simulations. At early stages, the appearance of multiple streamers is in qualitative agreement with experimental data. The number of streamers increases with Reynolds number which agrees with our previous theoretical prediction. Possibly due to the absence of walls, the streamers converge with time as in our previous simulation results based on an Eulerian approach. In itially, the energy of the fluid grows exponentially and the growth rates decrease with Reynolds numbers, which is similar to our previous works. Moreover, the simulation results indicate that the distribution of fibre orientations rapidly reach a state with a preferential alignment of fibres in the vertical direction.