The fragmentation and its mechanism of the uncoupled charge structure with segmental explosive

• Published in: Materials & design 2022-11, Vol.223, p.111224, Article 111224
• Main Authors: Li, Xiang, Huang, Guang-yan, Guo, Zhi-wei, Liu, Han, Feng, Shun-shan
• Format: Article
• Language: English
• Subjects: CEL numerical method; Fragmentation; Uncoupled charge; X-ray radiography
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2022.111224

[Display omitted] •A new charge structure of which the explosive is not coupled with the casing has been designed and studied.•The fragmentation shows a partition distribution in space and the velocity shows a piecewise acceleration in time.•The velocity direction of the uncoupled shell is consistent with its normal direction.•The high-pressure zone affects the acceleration of fragments and formation of cracks.•Dynamic pressure and static pressure co-dominated the uncoupled explosive driving process. Charge structure, which can instantly release much energy, is a significant research point in explosive protection and warhead. The distribution of the fragment velocity from uncoupled charge structures with segmental shaped explosive were studied. Numerical calculation research was carried out based on the CEL method. The X-ray photographic images of fragmentation were obtained from explosion experiment, which provided experimental support for numerical simulation research. The results show that the fragmentation and velocity distribution of the charge structure with segmental explosive show obvious segmental characteristics compared with the traditional cylindrical shell charge. The explosive loadings of the shell under uncoupled conditions is not only determined by the detonation wave and the static pressure of the detonation products but by the impact dynamic pressure of the detonation products at low pressure and high speed and the static pressure generated by the detonation products expansion and convergence, leading to the significant difference among the coupled side, the uncoupled side and the transition area. In this paper, the fragmentation and velocity distribution of the charge with segmental explosive was obtained, the uncoupled explosive driving mechanism was investigated and verified. The conclusion provides a foundation for exploring and establishing the uncoupled explosive driving theory.