Research On New Type Of Combined Annular Shaped Charge Technology

Annular shaped charge is a kind of shaped charge developed on the basis of linear charge,which is different from ordinary shaped charge in that its liner is annular structure.When the charge is detonated,the annular liner can produce annular jet in the shape of a ring under the action of detonation wave.Due to the large radius of the annular jet,which can usually reach above half of the charge diameter,it can achieve the target of creating large diameter holes on metal plate.Because of this characteristic,annular charge has a wide range of military and industrial application value,and it has important research significance.The double hull submarine has a good defense effect against the traditional torpedo.One of the effective ways to damage the double hull submarine is to apply shaped charge technology to torpedo,penetrate the submarine with shaped charge jet.But with the improvement of submarine protection capabilities,the damage effect of shaped charge jet on double hull submarine is gradually decreasing.To solve this problem,this paper puts forward the idea of using combined annular shaped charge structure in the warhead of torpedo to improve its damage ability on submarines.The specific research contents are as follows:(1)Proposed a new type of combined annular shaped charge structure.The characteristic of this structure is that the central charge is added to the hollow part of the annular charge,and two types of penetrators,annular jet and jetting projectile charge(JPC),are formed after the charge detonation.The formation process of these two types of penetrators is analyzed theoretically,and the velocity models of them are established based on the traditional shaped charge jet forming theory.The JPC's penetration ability is greatly affected by the difference of its tip and slug velocity.With the increasing of this velocity difference,the shape of the JPC gradually changes from similar to explosively formed projectile(EFP)to shaped charge jet.The velocity of annular jet is divided into axial velocity and radial velocity,which affect the rotation,elongation and expansion of annular jet respectively.(2)In this paper,the hydrocode software Autodyn is used to simulate the formation process of the combined annular charge,and the reliability of the theory is verified.The influence of the structure parameters on the performance of annular jet is studied,and a suitable range of parameters is obtained.By comparing the formation process of charge structure in water with that in air,it is found that the performance of annular jet and JPC decreases after penetrating into water.(3)The penetration performance of the combined annular shaped charge is studied,and it is found that the annular jet can create a hole with a diameter larger than the charge diameter on the target,but the penetration depth is small.While the JPC has a strong penetration ability against the target.The influence of structural parameters on the penetration ability of annular jet was studied,and the optimal blast height of the charge was determined.Finally,the structure optimization design of annular liner was carried out by taking penetration depth and aperture as indexes,and the optimal structural parameters of liner were obtained.(4)Numerical simulation studies were carried out on the process of the combined annular shaped charge penetrating the double shell structure,and a typical experiment was designed to verify the feasibility of the charge scheme.The penetration process of the double shell structure by charge explosion and jet generated by explosion is studied respectively.The results show that the double shell structure barely damaged by the charge explosion.While the two types of penetrators produced by the combined annular shaped charge can penetrate the double shell structure and cut a hole 1.4 times the diameter of the charge in the outer shell,which is beneficial to improve the damage effect of the subsequent detonation wave and bubble on the target.