3D Numerical Modelling of Mould Filling of a Coat Hanger Distributer and Rectangular Cavity

Abstract

Filling processes occur in a wide range of industries, ranging from packaging of consumer products to manufacturing processes for making polymeric, metal and ceramic components. These processes involve the complex interplay of extrusion of a viscous liquid into a mould or container where it displaces a gas phase. Numerical modelling based on computational fluid dynamics can be useful for understanding the filling process. However, complexity arises in that the fluid dynamics in both the viscous liquid and gas phase must be resolved while concurrently determining the location of the fluid-gas interface and the interaction of this interface with the solid surface, i.e., the wetting behaviour. Determining the free surface location and wetting behaviour is an integral part of the numerical method. Numerical methods have been applied to bottle and container filling for consumer products where the rheology can include shear thinning and viscoelastic effects and instabilities such as buckling and coiling may be prevalent [Tome, et al., 2001; Oishi et al., 2008; Roberts & Rao, 2011; Ville et al., 2011]. In metal casting simulations, the fluids are generally Newtonian, but complexity arises from the high injection rates leading to turbulent flow and temperature-dependent behaviour such as solidification [Ilinca & Hetu, 2000; Cross et al, 2006]. For injection moulding of polymers, time- and temperature-dependent effects are seen in conjunction with non-Newtonian rheology [Ilinca & Hetu, 2001; Kumar & Ghoshdastidar, 2002]. In powder injection moulding for ceramic and metal forming, a suspension of particles is injected into a mould to create a green part, which later sees further processing steps to produce the final part [Hwang & Kwon, 2002; Ilinca & Hetu, 2008]. Numerical methods for these problems range from finite difference, to finite volume, and finite element. General classes of algorithms for determining the location of the free surface include Eulerian, Lagrangian and arbitrary Lagrangian-Eulerian (ALE) descriptions. Eulerian methods use a fixed-grid with an interface capturing technique such as the volume of flu