Numerical Modeling of Aluminum Sampling Process

Abstract: Castings of aluminum alloys are widely used in the automotive and aerospace industries since they play a significant role in improving the performance and fuel efficiency. In aluminum industries, sampling is the most common method to evaluate the inclusion levels which is a key indicator for the quality of the aluminum alloys. Since how the filling process and solidification process will influence the inclusion characteristics during the sampling procedure is of great importance, the objectives of this work is to create a the two-phase flow model to simulate the filling process and solidification process, as well as calculate the particles movement in the whole sampling procedure. Computational Fluid Dynamics (CFD) modeling was used and this work was performed in the software ANSYS FLUENT. A numerical two dimensional (2D) axisymmetric model was built to simulate the sampling procedure with the assumption that the filling could be done along the main axis automatically. First, the initial solidification during the filling was taken into account without particle injection. The realizable k − ε turbulence model was used to model the effects of the turbulence. Several simulations with different inlet filling rate, different initial filling temperature and different inlet diameter was calculated to see the influence on the solidification behavior. Then, the whole sampling system was modeled with particle injection. The Discrete Phase Model (DPM) was used to simulate the particle motion in the melt and the focus was on the influence of the initial solidification on the inclusion distributions. Finally, the optimal sampling position inside the aluminum sampler mold was calculated.