Assessment of ability of RANS based turbulence models to predict the mould filling process and oxide film formation in Aluminum casting

摘要

Mould filling operations involve usually turbulent flow processes. Up to now a reliable evaluation of the effects of turbulence on the mold filling process along with the oxide film formation and disintegration does not exist. This paper aims to assess the ability of RANS based turbulence models in mould filling process in Rectangular Runner (RR runner) configuration in aluminum casting. For this purpose, three types of turbulence models have been considered for their specific capability throughout the literature. Different numerical simulations have been performed using various boundary conditions and pouring rates. It has been established that the k - ∈ - v~2 model is able to predict better the flow dynamics during the filling process. Based on the stability concept of the interface, a modified expression for the total amount of oxide films formed during this process has been introduced. This expression has been used to find an optimal pouring rate which led to 0.5m/s for RR runner under the investigated conditions.