Simulation of the interaction of conical impactors having an angle of attack with underwater barriers

Abstract

In this paper, the effect of the angle of impact and the angle of attack on the interaction between truncated coneshaped impactors made of BHZh-95 alloy and underwater barriers made of aluminum alloy is studied using experimental and computational methods. When such an impactor enters water, a supercavern appears around the impactor and minimizes the fluid friction. During the motion, the impactor afterbody periodically experiences impermanent contact with the walls of the supercavern, which maintains the steady motion. Note that the center of mass of the impactor is located closer to its afterbody, which can induce the angle of attack appearance during the motion. The experimental study is conducted using a hydroballistic track with high-speed video recording. The speed range of 250-350 m/s is considered. Mathematical modeling is carried out using the EFES original software package. It is revealed that a positive angle of attack β ≤ 10° leads to the normalization of the impactor and a decrease in the effective thickness of the barrier with its perforation. In contrast, at a negative angle of attack, the impactor rebounds from the barrier.