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The simulation is modeled as a 2D problem. On the pictures below, the geometry, computational model and mesh of the wall is shown.

Fig. 1.a: Geometry and dimensions	Fig. 1.b: Computational model	Fig. 1.c: Computational mesh

In case of bottom pipe casting from the side, concrete is filled in through the pipe (see Fig. 1.b). The diameter of the pipe is equal to 0.1 m (note, that is modeled as a 2D problem). Concrete is filled in with prescribed velocity equal to 0.2 m/s inside the pipe. No-friction bounadry conditions are assumed an all surfaces. Boundary conditions on the holes are prescribed in local coordinate system where normal component of velocity is forbidden and tangent component is free.

The material parameters of used concrete are following:

From the streamlines (curves that are instantaneously tangent to the velocity vector of the flow. These show the direction a fluid element will travel in at any point in time.) one can see, that there are certain regions in the structure, where the flow pattern is not developped (particularly the area above the openings on the right hand side). In these regions, some defects (such as air voids) can be expected.

These figures indicate the principal directions of deviatoric strain. It could be expected, that fibers will orient perpendicular to the shearing direction, if sufficient ammount of flow will be achieved. The principal directions change during the time, as the flow pattern is not stationary. In general, the figures indicate, that fibers become aligned along the walls and along the openings, where the largest shear strains rates are achieved. On the other hand, in the region on the right side, with rather small strain magnitude, the orientation of fibers will not be altered, however, the fibers may have been already oriented, while passing through an area with high shear strains, particularly at the area close to the outlet and in the right hand side corner. However, due to no-friction boundary conditions, no significant shearing happens and therefore, the orientation of fibres will remain in most of the volume rather random.

In this case, the casting has been performed from the outlet located at the bottom part at the centre. The figures of computational mesh and model are shown below.

Fig. 2.a: Computational model	Fig. 2.b: Computational mesh

The material parameters were the same as in the case of pipe filling:

Streamlines at different stages of solutions

Principal directions of deviatoric strain

Magnitudes of deviatoric strain

Video of casting simulation