Industrial and research experience has shown that casting quality is significantly affected by the flow of molten metal through the gating system before entering the mold cavity. In general, slow filling can lead to cold-shut and misrun defects, whereas rapid filling can cause sand inclusions and blow holes. The gating system comprises of one or more pouring basins, sprues, runners and gates, and optionally slag traps and filters. The number, location, shape and size of these elements determine the filling sequence and flow rate of molten metal into the mold cavity. Water, whose kinematic viscosity is of the same order as common molten metals, can be used for experiments; previous studies were however, limited to two-gate systems. In this work, flow of water and LM6 aluminum alloy through a multi-gate gating system have been compared using numerical simulation. This was followed by experimental observations of water flow in horizontal modular transparent multi-gate gating system developed in the lab, which showed similar trends as the numerical simulations. A statistical analysis of variance in the results of discharge observed with different combination of open gates provided useful insights. These insights are expected to reduce the dependence on computation-intensive CFD based simulations, reducing the total time required to optimize the gating system design for a given casting.
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