Atomization in High-Pressure Die Casting - Step 2 Simulation of Atomized Flow of Molten Aluminum by LES-VOF Method

The atomization of molten aluminum when injected during high-pressure die casting is analyzed to determine its effect in enhancing the strength of the product being cast. In the previously reported first step of this study, molten aluminum was injected into open space and its atomization was observed photographically. Now in the second step of the study, a simulation is conducted to determine how the molten aluminum becomes atomized at the injection nozzle (gate) and how this atomized material flows and fills the cavity. A new simulation method is developed based on large-eddy simulation coupled with the volume-of-fluid method. The simulation system is verified by comparing its output with photographs taken in the first step of the study. Simulations are then conducted using an approximation of a real cavity to visualize how it is filled by the atomized molten aluminum. The results show that the atomized material is conveyed through the cavity as a multiphase flow containing fine air bubbles, and that this multiphase flow persists until filling is complete.