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Airflow over a passenger train has been investigated experimentally and numerically in this research. The experimental model was a 1:26 scale model of a real train including a locomotive with one wagon behind it. A total of 16 pressure tabs for train were employed to measure the air pressure at various points on the model for different air flow velocity. Turbulent, incompressible and 3D model of air flow has been applied in numerical simulation. The numerical results of pressure coefficients were compared with the results obtained by the experimental investigation for the numerical simulation verification. The wagon number affect on the train drag coefficient and air pressure distribution on the symmetry plane of the train have been investigated numerically. The results show that the drag coefficient increases to 1.2336 for a locomotive and 7 wagons behind it but the air flow velocity has not a sensible affect on the drag coefficient. The averaged drag coefficient of each intermediate wagon has been obtained 0.1321.

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In the process of steel continuous casting, tundish as an intermediate compartment between the cauldron and mold has an important role in inclusion removal and the turbulence reduction process before entering the mold. Basically, the cleanliness of molten steel entering the mold is effected by the type of tundish flow pattern and the it’s behaviore in the flotation and removal of non-metallic impurities.Therefore, suitable flow pattern and increase of inclusion residence time in tundish improve the process of inclusion removal and lead to get clean steel. In this research, by manufacturing of the glass tundish in 1:4 scale to do flow physical modeling, the effect of melt height on the flow behavior in single tundish was studied, by implementing of dam in tundish then, its performance in inclusion removal is compared. Independent variables in this study are as the diameter of the inclusions and different water levels in the tundish and the dependent variables are as the separation rate of inclusions from the melt and inclusions residence time in the tundish. By increasing the water height in tundish, the inclusion removal and residence time get reduce. In addition, by using the dam near inlet nozzle the flow pattern gets improved and the inclusion removal will be as slag.