Modification of Axial Distribution of Fragment Velocity in Preformed Fragmentation Warheads

• Autorzy: Li Xin , Wang Weili , Liang Zhengfeng , Dong Jun

Identyfikatory

DOI

10.22211/cejem/186374

• Języki publikacji: EN

Abstrakty

EN

Fragment velocity is a crucial parameter for evaluating the destructive capability of a warhead, and it is typically calculated using the Gurney formula with corrections. The currently established correction formulas can determine the axial distribution of natural fragment velocity within the shell, but for a preformed fragmentation warhead, energy losses due to the existence of fragment gaps lead to calculated results that are larger than the actual values, making it unsuitable for accurate calculation of the axial distribution of fragment velocity in such warheads. This paper introduces a filling ratio correction function based on the concept of effective charge and establishes a calculation model for the axial distribution of fragment velocity in preformed fragmentation warheads. The numerical simulation method was validated using prototype ground static explosion test data, then the influence of key parameters such as charge diameter (d), length-diameter ratio (δ), and filling ratio (β) on the axial distribution of fragment velocity was investigated. The relationships between the three parameters (a, m, c) in the filling ratio correction function and the characteristic parameters were derived, and the filling ratio correction function and the calculation formula for the axial distribution of fragment velocity were fitted. Comparisons with existing empirical formulas indicate that the formulas established in this paper offer higher calculation accuracy, with an error of no more than 4.65% compared to measured values, and they can reliably determine the axial distribution of fragment velocity in preformed fragmentation warheads, providing significant practical application value.

Słowa kluczowe

EN

preformed fragmentation warhead; velocity; length-diameter ratio; filling ratio; calculation formula

• Czasopismo: Central European Journal of Energetic Materials
• Rocznik: 2024
• Tom: Vol. 21, no. 1
• Strony: 22--52
• Opis fizyczny: Bibliogr. 25 poz., rys., tab., wykr.

Twórcy

autor

Li Xin

• Naval University of Engineering, China
• Xi‘an Modern Chemistry Research Institute, China

autor

Wang Weili

• Naval University of Engineering, China

autor

Liang Zhengfeng

• Xi‘an Modern Chemistry Research Institute, China

autor

Dong Jun

• Xi‘an Jiaotong University, China

Bibliografia

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