Research on the Migration Patterns of Sand Dust in a Chongqing Foundry Company Based on Numerical Simulation

Abstract To clarify the impact of thermal plumes on the migration of casting sand dust, a semi-enclosed sand falling station at a foundry company in Chongqing was selected as the research object. On-site dust detection was conducted, and a CFD-DPM gas-solid two-phase flow model was established without applying The results indicate that the total dust concentration around the sand falling machine is 8.0-11.0 mg/m³, and there is significant dust pollution in the working area. As the high-temperature casting continues to cool, a vertical thermal plume gradually forms above the heat source. The peak velocity along the centerline increases from approximately 0.33 m/s at 1 second to about 0.49 m/s at 9 seconds. At 12 seconds, the peak remains relatively unchanged, but the high-speed region in the middle and upper parts continues to expand. The peak dust concentration is always located near the sand falling platform. As the thermal plume develops, the dust concentration in the middle and upper parts gradually increases, and the dust impact range continues to expand upward. In the later stages of the simulation, the temperature field, velocity field, and dust concentration field within the Research indicates that the upward airflow generated by thermal buoyancy plays a crucial role in the vertical migration of falling dust. The area above the heat source and the deflection zone at the top of the equipment are key positions that require focused attention for dust control.