类椭圆截面弹侵彻有限厚混凝土靶板弹道特性

To investigate the ballistic characteristics of a quasi-elliptical cross-section projectile penetrating into finite-thick concrete target,the tests are made on the normal and oblique penetrations of quasi-elliptical cross-section projectiles into the concrete targets with different thicknesses. The variation trends of the longitudinal acceleration and trajectory deflection angle of projectile during different penetrating stages are analyzed through the numerical simulation using the finite element method-smooth particle Galerkin (FEM-SPG) algorithm. The effects of impact velocity,target plate thickness,oblique angle,rolling angle and angle of attack on the trajectory deflection are discussed. The research results show that the trajectory deflects toward the flatter surface and the deflection mainly occurs in the tunnel stage and the plugging stage when a quasi-elliptical cross-section projectile penetrates into a target plate with finite thickness. As the thickness of the target plate increases,the trajectory deflection angle increases. The deflection caused at the cratering stage is only 1. 4% of the final deflection angle in numerical simulation. There is a critical impact speed,which makes the deflection angle of the normal penetration trajectory decrease with the increase of the penetration speed above this target impact speed, while below this critical value, an inverse relationship is observed. Furthermore,the critical speed demonstrates non-monotonic dependence on target thickness, exhibiting an initial increase followed by progressive reduction until stabilization occurs. The trajectory changes from downward deflection to upward deflection with the increase in the angle of attack (- 6° - 6°) when the projectile penetrates into a target at the same oblique angle. The trajectory has excellent stability within the range of 0°-30° oblique angle at 2° angle of attack. The attitude stability of the projectile generally weakens first and then increases with the increase of the rolling angle on Oxz plane. When the rolling angle is less than 150°,the projectile shows a negative angle of attack after it ends interacting with the target.