Reactive Armor Jet Interference Mechanism

The disturbance process and mechanisms of the shaped charge jet by ERA are studied by the theoretic models ,numerical simulation and experiment methods in this paper. The discontinous and continous disturbance models of the shaped charge jet by the single lay sandwich, double lays parallel and the V-shaped structure ERA are established. The methods of calculating the variation of the diameter of the disrupted jet, excursion degree, the penetrating capability of the residual jet are given. the X-ray photography of the shaped charge jet by the sandwich explosive, the velocity of the plates of the explosive reactive armor, the disturbed time of the jet by the moving plates are obtained by the experiment. The disturbance capabilities of the single lay sandwich, double lays parallel and V-shaped sandwich structure to the jet are compared.The relation between the disturbance capability of the ERA and the impact angle of the jet, the V-shaped angle and the structure of ERA are attained.The research results show: the moving paltes have great disturbance and incision after the sandwich explosive ignites, they decrease the penetration capability of the jet through deviating the way of the jet, bending the jet and dispersing the impact point on the target. The diameter of the penetration hole of the jet is smaller, the time of the jet disturbed is shorter, the numbers of the breakup jets and the disturbance capability increase when the thickness of the plate is larger. The velocity difference between the jet head and tail is more, the amount of the escape jet and the ant-disturbance capability of the jet increase when the velocity of jet is high. The high velocity jet form the mail hole on the target ,and the low velocity jet form affiliated pits on the target because the ant-disturbance capability of the escape jet weaken, and the deviation is large. when the jet impacts the ERA normally, the deviation and bend of the jet are not obvious. When the jet impacts the ERA obliquely, the penetration capability redeues by 55%～75%. The disturbance capability increase with the increase of the impact angle. The disturbance capability of the double lays and V-shaped sandwich structure to the jet are stronger than the single sandwich. Variations of V-shaped angles can't disturb observably penetration of jet.