On the Possibility of Increasing Rocky Target Penetration Depth for Compound Penetrators Featuring a Tail Assembly Jettisoned at Impact

The paper considers the possibility of increasing rocky target penetration depth for compound penetrators equipped with a tail assembly that is jettisoned at impact. The jettisoned ballast mass of the tail assembly featured a tubular part assuming the role of a launch tube housing a penetrating unit. When the ballast mass is jettisoned in the direction opposite to the penetration direction, this additional impulse pushes the penetrating unit in the direction of its motion, which may result in increasing the penetratio depth of the unit. We conducted our research using a computational model that presents the penetrating unit and the ballast mass as axisymmetric nondeformable bodies moving due to the forces generated by the resistance of the target and by the propellant gas pressure, said forces acting upon the bodies under consideration at the moment of jettisoning. We also assumed that the propellant gas pressure is constant for the jettisoning duration. Our computations detected that, for targets similar to dense ground and rock, the following factors affect the increase in penetration depth: mass ratio of the jettisoned and penetrating parts of the penetrator; the moment when the ballast mass is jettisoned; the jettisoning pressure; the length of the tubular part, which determines how long the propellant gases will be able to push the penetrating unit

The study was partially supported by RFBR (grant no. 15-08-08319-a)

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