Optimum structure of Whipple shield against hypervelocity impact

18th APS-SCCM; 24th AIRAPT

Lee, M.^1

Department of Mechanical Engineering, Sejong University, 98 Kunja-Dong, P-Seoul

143-747, Korea, People's Democratic Rep^1

关键词: Aluminum projectiles;    Early stage simulation;    Hypervelocity impacts;    Impact velocities;    Optimum structures;    Optimum thickness;    Rectangular coordinates;    Smooth particle hydrodynamics;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/11/112039/pdf
DOI  :  10.1088/1742-6596/500/11/112039

来源: IOP

【 摘 要 】

Hypervelocity impact of a spherical aluminum projectile onto two spaced aluminum plates (Whipple shield) was simulated to estimate an optimum structure. The Smooth Particle Hydrodynamics (SPH) code which has a unique migration scheme from a rectangular coordinate to an axisymmetic coordinate was used. The ratio of the front plate thickness to sphere diameter varied from 0.06 to 0.48. The impact velocities considered here were 6.7 km/s. This is the procedure we explored. To guarantee the early stage simulation, the shapes of debris clouds were first compared with the previous experimental pictures, indicating a good agreement. Next, the debris cloud expansion angle was predicted and it shows a maximum value of 23 degree for thickness ratio of front bumper to sphere diameter of 0.23. A critical sphere diameter causing failure of rear wall was also examined while keeping the total thickness of two plates constant. There exists an optimum thickness ratio of front bumper to rear wall, which is identified as a function of the size combination of the impacting body, front and rear plates. The debris cloud expansion-correlated-optimum thickness ratio study provides a good insight on the hypervelocity impact onto spaced target system.