Numerical analysis for aerodynamic characteristics of electromagnetic launch hypervelocity projectile

The numerical method was used to study the aerodynamic flow field characteristics of hypervelocity projectiles, especially in the reentry phase. The prediction accuracy of S-A and k-ω SST turbulence model was verified by wind tunnel test data. The calculation results show that the prediction accuracy of the two turbulence models is higher than 2% in normal force prediction. In axial force prediction, the S-A turbulence model has a high prediction accuracy of 4.6%. When the projectile reenters at a large angle of attack, the transverse flow effect of projectile is more obvious. The shock wave makes the surface pressure of the projectile increase sharply on the windward side, while the large-scale streamwise vortex structure formed on the leeward side reduces the pressure, and the increase of the pressure on the windward side has a greater impact on the aerodynamic coefficient of projectile. The aerodynamic drag and lift coefficient at high angle of attack are obviously nonlinear, the drag coefficient is obviously increased, and the static stability margin is also sharply reduced, which makes the convergence characteristics of projectile worse, and that is treated as the main reason for the velocity attenuation during the reentry process of projectile. © 2022, NUDT Press. All right reserved.