中图分类号：0385 国标学科代码：13035 文献标志码：A

Abstract：Inthe processofdeeppenetrationofteearth penetration weapon（EPW）atacking theundergroundtarget，the nonideal penetrationatitudewithaninitialatackangle isinevitable，whichwillintroducetransverseoverload withalargepeak value for the earth penetrator. It could damage some important components ofthe earth-penetrating projectile and redue the penetration eficiencyof theprojectile.Therefore，itis necesary tostudythemethodologyofreducingthetransverseoverload peak value of theearth-penetrating projectile.However，the previous research onthe earth-penetrating projectile seldom consideredtheinfluenceoftransverseoverload，makingitdiiculttoefectivelyreducethetransverseoverload.Inoderto overcome this problem，a numerical simulation method wasused tostudythe special tansverse overload shedding effect and its mechnism ofa new type ofearth-penetrating projectile with aserated configuration penetrating concrete targets at nonzeroattack angles.Theinfluencesof the initial atack angleand thecoeficientof thecenterofmassof the projectile were studied，and the motion，ontactforce，contactmoment，andcontactareaofteprojectile wereaalyzedusingaconventioal smooth projectile for comparison. The results show that for small initial attack angles of 0 and ， the peak value of transverse overload of the serrated projectile is reduced by about 3 0 . 6 % 5 . 2 % ，and 1 1 . 3 % ，respectively， compared to the smooth projectilebutthepeak valueofcontactmoment，pulsewidth，anddeflectionangleareincreased.Theresearchreveals themechanical mechanismtoreduce transverse overload： theserated bodyof the projectilereduces thecontactareabetween the projectileandthetarget，andthetransversecontactforceismainlyconcentratedontheuppersurfaceoftherightserated partsofthe first twoseated groovesnear theheadofthe projectile；the transversecontactforce betweentheserratedbodyand thetarget decreases，while the transverse contact force between the non-serrated parts （mainlythe head of the projectile）and thetargetincreases.Therefore，these twopartsof the projectilecompeteandcontrolthereductioneffectsofthetransverse overloadofthewholeprojectileintheprocessofdeeppenetrationwithaninitialattckangle.Whenoptiizationsofstructural designare used tosuppresste ballstic deflection oftheserrated projectile，，the transverse overload shedding eficiencyof serrated projectiles can be effectively improved.

Keywords： transverse overload shedding； attack angle； serrated projectile；deflection of trajectory

为应对冲击动力学问题，人们发展了大量安全可靠的冲击防护结构[1-3]和高侵彻能力的武器装备[4-5]。现代化战争中，随着地面目标的加固防护及高价值目标等的深埋防护，使钻地武器成为有效打击和威慢此类目标的重要手段。为提高钻地弹的打击效率，在维持弹体结构完整性的前提下，需尽可能加大弹体的侵彻深度。通过优化弹头形状[6-10]、增大弹体长径比[1]、提高弹体初始撞击速度[12I、优化弹材和质量比[4]等，能够实现钻地弹最大侵彻深度的提升。然而，由于钻地过程中存在靶体不均匀及不对称性、弹体侵蚀和变形、弹体飞行时气动扰动等因素影响，实际弹体通常以非理想正侵彻姿态着靶，即弹体着靶的倾角和攻角非零，影响钻地弹的侵彻和打击能力[13]。

对非正侵彻过程中钻地弹的动力学问题已有很多研究[13-22]。非正侵彻姿态将引人垂直于弹轴的横向作用力。横向作用力一方面推动弹体沿垂直于弹体轴向的平动，另一方面促使弹体绕质心转动，从而减小弹体的有效侵彻深度。过大的横向作用力还可能导致弹体结构弯曲甚至被破坏，从而降低弹体的侵彻能力。与倾角相比，攻角对弹体偏转的影响更大。为此，学者们开展了抑制弹体偏转的研究，通过优化弹体质心系数[20]、弹身变径结构设计（尾裙等）[23-24]、弹体着靶姿态控制[13.25]等提升弹体的弹道稳定性。若弹体在整个侵彻过程中均不发生明显的结构弯曲，常规设计的弹体在弹身全部埋入靶内后，弹道轨迹近似为直线[17.26]。……