Symmetrical form of the two-component fluid flow’s stability curve as a part of analysis devices

Abstract

Abstract The devices for analysis have different channels for mixing and separating flows. The media in most cases is multicomponent and predicts special properties. The constitutive equation FENE-P is chosen as a rheological model to describe a non-Newtonian fluid that has particles that can change their conformation. This model predicts properties such as viscosity anomaly, finite stress relaxation time, and dependence of the longitudinal viscosity on the longitudinal strain rate. For the non-Newtonian fluid the effect of the shape’s symmetry loss and manifestation of asymmetry are possible. The Weissenberg number (We) and the degree of stretching of the flexible particle (L2) are the determining parameters of the flows of such fluids. In this work the values of these modeling parameters, at which the flow behaviour changes so that the initial symmetrical flow form becomes unstable and turns into asymmetrical form even in laminar creeping flow (Re<<1) have been established. A number of numerical experiments have been carried out and the dependence of the manifestation of instability of the symmetrical flow form on the set of values of We and L2 has been obtained. The simulation results with the Newtonian fluid. The solution is obtained using the finite volume method (FVM) in the OpenFOAM software environment.