考虑刚性弹弹头形状的混凝土(岩石)靶体侵彻深度半理论分析

基于动力球型空腔膨胀理论和冲击成坑+钻孔区两阶段侵彻模型,以截卵形弹头弹体为例,运用曲面积分,引入表征弹头形状和弹靶摩擦效应的量纲一系数、质量比和冲击因子,提出了综合考虑弹头形状变化、成坑区深度、弹靶摩擦阻力的混凝土和岩石靶体的刚性弹垂直侵彻深度的计算公式。该公式在相关参数取特殊值时,可退化为经典的侵彻深度计算公式。通过与8组不同弹头形状弹体冲击混凝土和岩石靶体的侵彻实验数据、已有10个(半)经验公式计算结果对比,验证了本文公式的适用性。并结合实验和参数影响分析,给出了混凝土和岩石靶体的弹靶摩擦系数和与冲击因子相关的不同弹头形状弹体成坑系数的建议值。

Semi-theoretical analyses for penetration depth of rigid projectiles with different nose geometries into concrete (rock) targets

Basedonthedynamicsphericalcavity-expansiontheoryandthetwo-stagepenetrationmodelconsistingofcrateringandtunneling,adimensionlessformulawasproposedfornormalpenetrationdepthofrigidprojectilesintoconcreteandrocktargetsbytakingatruncated-ogivenoseprojectileasanexample.Intheproposedformula,thesurfaceintegrationmethodwasapplied,andthemassratioandtheimpactfactorwereintroduced,aswellasthedimensionlesscoefficientsdenotingtheprojectilenosegeometryandtheprojectile-targetfrictioneffect,toconsiderthevariationofprojectilenosegeometry,crateringdepth,andtangentialresistanceonprojectiles.Andtheproposedformulacanberegressedtotheclassicpenetrationformulaeinspecialcases.Theproposedformulawasvalidatedbycomparingthepenetrationdepthspredictedbytheproposedformulawiththosepredictedbytheexistingtenclassicempiricalandsemi-empiricalformulaeaswellastheexperimentaldatafromeightfieldshottestsofconcreteandrocktargetshitbyprojectileswithdifferentnosegeometries.Basedonthetestsandparametricanalyses,thecorrespondingparametervalueswererecommendedaimingtodifferentnoseprojectiles,includingthedynamicprojectile-targetfrictionalcoefficientofconcreteandrocktargets,aswellasthelinearcoefficientofcrateringdepthrelatedtotheimpactfactor.