Direct observation of flow of metal during casting process is difficult. Phenomena such as jetting, and the entrapment of gas bubbles during turbulent flow are extremely difficult to be treated by mathematical modeling, and physical modeling such as water modeling could be used. The fluid flow during the permanent mold casting of copper alloys was simulated using water modeling. Three full-scale models of molds used in gravity and low-pressure permanent mold casting processes were fabricated in transparent plexiglass. A mixture of water and glycerol with a viscosity close to liquid copper was used as the fluid and the flow was recorded suing high-speed video. The modeling indicated that turbulent flow in the pressurized gating system promoted gas entrapment and jetting. It was shown that modifications in the gating system could promote more laminar flow and eliminate or reduce the defects.
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