Numerical simulation of fiber suspension in a two dimensional cavity

Modelling of fiber suspension in injection molding cavities is very complex, with fluid flow, fiber orientation, and heat transfer effects taking place at the same time. Moreover, the flow is modified by the presence of fibers and vice versa. Therefore, the aim of the paper is to develop a Computational Fluid Dynamics (CFD) model to simulate and characterise the fiber suspension flow in two dimensional mold cavities. The model is intended to describe the fluid flow and heat transfer aspects of the suspension, and to predict the fiber orientation. The Navier-Stokes equations and the Jeffery (1922) equation are the governing equations for the velocity field and fiber motion respectively. The flow is considered to be two-dimensional incompressible, non-isothermal,transient and behave as non-Newtonian fluid containing suspension of short-fibers. The Finite Volume Method (FVM) combined with Control Volume Method is used to simulate the flow field by solving the momentum, energy and fiber orientation equations. To validate the numerical model, the numerical results are compared with available experimental findings. A good agreement between the numerical results and the experimental data is achieved. Since the behaviour of fiber suspension has great significance on the quality of the final product, this study has wide background of engineering application.