撞击姿态对构型弹体非正侵彻多层间隔钢靶弹道特性的影响规律

Influence rule of impact attitude on trajectory characteristics of warhead’s non-normally penetration into multi-layer spaced steel target

为深入认识构型弹体非正侵彻多层间隔靶板的弹道偏转规律,结合数值模拟和理论分析,研究了构型弹体在不同撞击姿态下侵彻多层间隔钢靶的弹道特性,其中引入弹体侧向接触力和侧向偏转力矩等参量,着重分析撞击着角和攻角对弹道特性的影响规律。结果表明:构型弹体非正侵彻过程中,在纵向发生阶梯式速度衰减,但变化较小;同时,由于穿靶过程中受到侧向接触力及其偏转力矩的作用,在侧向产生显著弹道偏转。撞击着角决定弹体所受外载荷的非对称程度,着角越大,弹体偏转越严重;撞击攻角则主要影响弹肩穿靶时的径向速度和弹尾穿靶时的触靶位置,二者共同影响弹道轨迹,因而存在使弹体偏转程度发生转折的临界攻角。相比于侵彻单层靶,构型弹体非正侵彻多层间隔靶板的显著特点为弹道偏转存在累积效应,且侵彻前一靶板的弹道偏转情况显著影响到侵彻后一靶板时的弹靶作用特征,进而导致弹道偏转与弹靶接触力互相耦合。相关研究对预测构型弹体侵彻多层间隔靶板性能、优化弹体构型和撞击姿态等具有较好的指导价值。

In order to deeply investigate the trajectory deflection characteristics of a warhead during the non-normal penetration into the multi-layer spaced target,the trajectories under different impact attitudes are analyzed with combined numerical simulation and theoretical analysis,in which finite element method(FEM)simulations on the penetration process under various impact conditions are conducted systemically,and the deformation and failure morphologies of warhead and target as well as the interaction characteristics between them are discussed in detail.Besides some feature parameters,lateral contact force and angular moment,are introduced in the theoretical analysis.Furthermore,the influence rules of oblique angle and attacking angle on the trajectory deflection characteristics are investigated in detail.Related results indicate that during the non-normal penetration into multi-layer spaced target,the warhead behaves as small staged axial velocity decay combined with obvious lateral trajectory deflection,and the trajectory deflection is mainly derived from the lateral contact force as well as the corresponding angular moment,and the lateral contact force mainly makes its effect during three periods,i.e.,when the nose,shoulder and tail of warhead pass through the target,respectively.The oblique angle mainly affects the degree of external load asymmetry exerting on the warhead with increase of the oblique angle,the downward lateral contact force as well as the corresponding angular moment exerting on the warhead all increase,thus the trajectory deflection becomes more severe.Comparatively,the attacking angle determines two factors,one is the radial velocity of warhead at the time when its nose passes through the target,and another is the contact position between the warhead and target when the warhead tail passes through the target.These two factors determine the trajectory simultaneously,so different attacking angles make the lateral contact force and the corresponding angular moment differing from each other during the process of the warhead tail passing through the first target,leading to a critical attacking angle at which the evolution trend of trajectory deflection would turn the other way round.Compared to the penetration into a single layer target,a remarkable feature in the penetration of a warhead into the multi-layer spaced target is that the trajectory deflection shows a cumulative effect,and the situation in the penetration into the former target plate significantly affects the interaction condition between the warhead and the latter target plates,and this further results in a coupling effect between the trajectory deflection and the contact force.The present investigation is of good significance in the practical engineering application,e.g.,predicting the penetrating ability of a warhead into the multi-layer spaced target,and optimizing the warhead structure and its impact attitude,etc.