The relationship between the average penetration velocity,UˉUˉ,and the initial impact velocity, V0V0,in long-rod penetration has been studied recently. Experimental and simulation results all show the linear relatio...The relationship between the average penetration velocity,UˉUˉ,and the initial impact velocity, V0V0,in long-rod penetration has been studied recently. Experimental and simulation results all show the linear relationship between UˉUˉ and V0V0 over a wide range of V0V0 for different combinations of rod and target materials. However, the physical essence has not been fully revealed.In this paper, the Uˉ?V0Uˉ?V0relationship is profoundly analyzed using hydrodynamic model and Alekseevskii-Tate model. Especially, the explicitUˉ?V0Uˉ?V0 relationships are derived fromapproximate solutions of Alekseevskii-Tate model. Besides, the decelerationin long-rod penetration is discussed. The decelerationdegree is quantified by adeceleration index,α=2μˉ/(KΦJp)≈Ypρ?1/2p(ρ?1/2p+ρ?1/2t)V?20α=2μˉ/(KΦJp)≈Ypρp?1/2(ρp?1/2+ρt?1/2)V0?2, which is mostly related to the impact velocity, rod strength and rod/target densities. Thus, the state of penetration process can be identified and designed in experiments.展开更多
基金The work was supported by the National Natural Science Foundation of China (Grant 11872118)The authors want to express deep gratitude to the reviewers for their sound comments and helpful suggestions.
文摘The relationship between the average penetration velocity,UˉUˉ,and the initial impact velocity, V0V0,in long-rod penetration has been studied recently. Experimental and simulation results all show the linear relationship between UˉUˉ and V0V0 over a wide range of V0V0 for different combinations of rod and target materials. However, the physical essence has not been fully revealed.In this paper, the Uˉ?V0Uˉ?V0relationship is profoundly analyzed using hydrodynamic model and Alekseevskii-Tate model. Especially, the explicitUˉ?V0Uˉ?V0 relationships are derived fromapproximate solutions of Alekseevskii-Tate model. Besides, the decelerationin long-rod penetration is discussed. The decelerationdegree is quantified by adeceleration index,α=2μˉ/(KΦJp)≈Ypρ?1/2p(ρ?1/2p+ρ?1/2t)V?20α=2μˉ/(KΦJp)≈Ypρp?1/2(ρp?1/2+ρt?1/2)V0?2, which is mostly related to the impact velocity, rod strength and rod/target densities. Thus, the state of penetration process can be identified and designed in experiments.
