Research On The Influence Factors And Speed Threshold Of Hexagonal Prism Fragments Impacting Initiation Comp B With Shell

Axial prefabricated fragment warhead can effectively intercept air targets such as missiles, which will form a high-speed and dense fragments barrier in the air after explosion. It is one of the main development directions of orientation damage fragmentation warhead.The main structure of the prefabricated fragments are spherical and cylindrical. Although, there is few research on hexagonal prism fragments. The hexagonal prism fragments is more intensive arrangement, more quantity and better effect in a limited space. Therefore, studying on the influence factors and speed threshold of hexagonal prism fragments impacting initiation the explosive with shell has an important meaning for the designing of preformed fragment warhead.Firstly, tests about hexagonal prism of 12 impacting initiation the Comp B with shell were carried out. The speed threshold which can make Comp B occur more intenser reaction than combustion was got. In addition, numerical simulation is conducted applying Autodyn-3D software to study the impacting initiation speed threshold of Comp B with shell. What's more, the impacting initiation criterion of Comp B with shell was got applying numerical simulation results. The influence of the aspect ratio of fragments, shell thickness on single pieces hexagonal prism fragments speed threshold was studied and response characteristic was got.Considering the effect of fragments group on the target in the actual process, The double hexagonal prism fragments was chosen as the research object. The speed threshold and response characteristic of Comp B occurring explosion was studied when double fragments impacting initiation explosive in different spacing at the same time or two fragments impacting initiation explosive in different spacing and different time. applying numerical simulation method. Results show that when double fragments impacting initiation Comp B with shell, the longer double fragments is, the higher the speed threshold is. While, the impacting effect of double fragments is the same as single fragment when the distance of double fragments is long enough.Finally, the influence of fragment shape on speed threshold of impacting initiation Comp B with shell is studied. When the quality of spherical fragment, cylindrical fragment, cuboid fragment are the same, research on the effect of target shell thickness of and fragments frontal area on speed threshold of impacting initiation Comp B with shell. In addition, their impacting initiation criterion was calculated. Calculation results show that the speed threshold of spherical fragment is the highest, followed by cylindrical fragment, the spherical fragment is the lowest. At the same time,we find that the speed threshold of spherical fragment, cylindrical fragment, cuboid fragment tends to the same value when the target shell thickness increases a certain value.The conclusions mentioned above have an important reference for the design of preformed fragment warhead.