【摘 要】
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Based on the Navier-Stokes (N-S) equations of incompressible viscous fluids and the standard k-ε turbulence model with assumptions of steady state and two dime
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Based on the Navier-Stokes (N-S) equations of incompressible viscous fluids and the standard k-ε turbulence model with assumptions of steady state and two dimensional conditions,a simulation of the aerodynamic drag on a maglev train in an evacuated tube was made with ANSYS/FLOTRAN software under different vacuum pressures,blockage ratios,and shapes of train head and tail.The pressure flow fields of the evacuated tube maglev train under different vacuum pressures were analyzed,and then compared under the same blockage ratio condition.The results show that the environmental pressure of 1 000 Pa in the tube is the best to achieve the effect of aerodynamic drag reduction,and there are no obvious differences in the aerodynamic drag reduction among different streamline head shapes.Overall,the blunt-shape tail and the blockage ratio of 0.25 are more efficient for drag reduction of the train at the tube pressure of 1000 Pa.
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