Noise-Induced Oscillations in the flow of Concentrated Suspensions

The flow of a concentrated suspension with an N-shaped dependence of the shear rate on the shear stress applied to the system is investigated. A mathematical model with two dynamic states, a steady-state and an self-oscillatory state, is examined. It is shown that, in the zone of steady-state flows possessing a determinate stability, even small fluctuations in the shear stress can give rise to large amplitude oscillations in the flow rate. These noise-induced oscillations are analysed using the technique of stochastic response functions. Theoretical results using a parametric description of their dispersion are presented for the stochastic flow oscillations observed in the model.