Viscous resuspension of a sediment caused by oscillating stratified flows
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It is known that a sediment of settled particles can resuspend under the action of shear. In this paper, based on a mathematical model given by Leighton and Acrivos , we study theoretically the viscous resuspension of a sediment in a Couette channel with harmonically oscillating walls. Numerical experiments reveal that the resuspension height and the particle volume concentration at the bottom of the channel depend on the frequency of the oscillation. While oscillation of the top wall has nearly no influence on the sediment, a moving bottom wall causes the settled particles to completely resuspend if the frequency is large enough.
KeywordsMathematical Model Dynamical System Fluid Dynamics Numerical Experiment Transport Phenomenon
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