Numerical simulation of effect of fiber in polymeric fluid with fiber suspensions
For polymeric fluid with fiber suspensions,a multi-scale model was developed.The model coupled the rheologic behavior of incompressible flow field on the macro-scale,the effect of transient orientation of the fiber on the meso-scale,and the information of probability distribution of finite extensible nonlinear elastic(FENE) dumbbell model on the polymeric molecular level.The governing equations for the polymeric flow field,the composite stress,the distribution of molecular chain configurations and fiber orientation were coupled and solved simultaneously.The semi-implicit method for pressure linked equations revised and finite difference method on source term(SIMPLER-FDMS)method was used to calculate the multi-scale governing equations.In the simulation of 4∶1 isothermal planar contraction flow,the validity of the multi-scale model was proved by the analysis of distribution of normal stress difference,shear stress,and the fiber orientation ellipse.For investigating the effects of fiber parameters on the viscoelastic behavior and fiber orientation probability of polymeric fluid with fiber suspensions,a parametric study about the fiber concentration,fiber-fiber interaction and fiber aspect ratio was conducted.