To quickly break through a reinforced concrete wall and meet the damage range requirements of rescuers entering the building,the combined damage characteristics of the reinforced concrete wall caused by EFP penetratio...To quickly break through a reinforced concrete wall and meet the damage range requirements of rescuers entering the building,the combined damage characteristics of the reinforced concrete wall caused by EFP penetration and explosion shock wave were studied.Based on LS-DYNA finite element software and RHT model with modified parameters,a 3D large-scale numerical model was established for simulation analysis,and the rationality of the material model parameters and numerical simulation algorithm were verified.On this basis,the combined damage effect of EFP penetration and explosion shock wave on reinforced concrete wall was studied,the effect of steel bars on the penetration of EFP was highlighted,and the effect of impact positions on the damage of the reinforced concrete wall was also examined.The results reveal that the designed shaped charge can form a crater with a large diameter and high depth on the reinforced concrete wall.The average crater diameter is greater than 67 cm(5.58 times of charge diameter),and crater depth is greater than 22 cm(1.83 times of charge diameter).The failure of the reinforced concrete wall is mainly caused by EFP penetration.When only EFP penetration is considered,the average diameter and depth of the crater are 54.0 cm(4.50 times of charge diameter)and 23.7 cm(1.98 times of charge diameter),respectively.The effect of explosion shock wave on crater depth is not significant,resulting in a slight increase in crater depth.The average crater depth is 24.5 cm(2.04 times of charge diameter)when the explosion shock wave is considered.The effect of explosion shock wave on the crater diameter is obvious,which can aggravate the damage range of the crater,and the effect gradually decreases with the increase of standoff distance.Compared with the results for a plain concrete wall,the crater diameter and crater depth of the reinforced concrete wall are reduced by 5.94%and 9.96%,respectively.Compared to the case in which the steel bar is not hit,when the EFP hit one steel bar and the intersection of two steel bars,the crater diameter decreases by 1.36%and 5.45%respectively,the crater depth decreases by 4.92%and 14.02%respectively.The EFP will be split by steel bar during the penetration process,resulting in an irregular trajectory.展开更多
采用LS-DYNA对在药型罩上粘附隔板结构形成带尾翼型爆炸成型弹丸(explosively formed projectile,EFP)进行三维数值模拟,从药型罩微元压跨速度和压力的角度初步探讨了形成尾翼型EFP的机理,对同一直径的大锥角型、球缺型和弧锥结合型药...采用LS-DYNA对在药型罩上粘附隔板结构形成带尾翼型爆炸成型弹丸(explosively formed projectile,EFP)进行三维数值模拟,从药型罩微元压跨速度和压力的角度初步探讨了形成尾翼型EFP的机理,对同一直径的大锥角型、球缺型和弧锥结合型药型罩形成的尾翼型EFP进行了对比分析,三种结构药型罩均能形成较为明显的尾翼,其中大锥角型药型罩得到的EFP速度最高。数值计算结果表明,EFP尾翼数与药型罩上所粘贴的隔板数一致,三种不同结构药型罩上粘贴四个隔板,得到的尾翼数均为四个。通过实验,对贴隔板法形成尾翼EFP做了进一步验证,实验结果与数值模拟结果基本一致。展开更多
针对同一成型装药形成多模毁伤元问题,利用LS-DYNA动力有限元程序,采用流固耦合方法,对在药型罩前加装一刻槽圆环形成带尾翼爆炸成型弹丸(explosively formed projectile,EFP)的成型过程进行了数值模拟,结果表明,该装药结构能形成带有8...针对同一成型装药形成多模毁伤元问题,利用LS-DYNA动力有限元程序,采用流固耦合方法,对在药型罩前加装一刻槽圆环形成带尾翼爆炸成型弹丸(explosively formed projectile,EFP)的成型过程进行了数值模拟,结果表明,该装药结构能形成带有8个尾翼的EFP,带尾翼EFP的长径比是EFP长径比的2.75倍,其头部速度比EFP增加了15%,实现了带尾翼大长径比EFP和EFP两种模态的转换。展开更多
由于规律性尾翼EFP(Explosively Formed Projectile)具有较好的飞行稳定性,为此对大炸高条件下EFP飞行稳定性进行研究。提出一种新型形成尾翼的简易方法,即在药型罩上粘附隔板,利用隔板改变爆轰波阵面的结构形状,从而改变药型罩的变形规...由于规律性尾翼EFP(Explosively Formed Projectile)具有较好的飞行稳定性,为此对大炸高条件下EFP飞行稳定性进行研究。提出一种新型形成尾翼的简易方法,即在药型罩上粘附隔板,利用隔板改变爆轰波阵面的结构形状,从而改变药型罩的变形规律,形成一种带有尾翼的EFP。首先从理论上探讨了该方法的可行性,根据理论分析结果设计了不同尺寸的隔板。然后通过实验验证理论分析结果,最后采用LS-DYNA对尾翼EFP形成过程进行数值模拟。结果表明:在药型罩上粘贴隔板可以形成尾翼EFP,尾翼EFP形状与隔板尺寸具有一定的相关性。展开更多
为了准确描述爆炸成型弹丸(Explosively Formed Projectile,EFP)垂直侵彻有限厚靶板后效破片云的形状,基于量纲分析及正交设计理论,利用AUTODYN软件中SPH算法研究了EFP成型参数、弹靶材料参数对靶后破片云形状的影响,建立了EFP垂直侵彻...为了准确描述爆炸成型弹丸(Explosively Formed Projectile,EFP)垂直侵彻有限厚靶板后效破片云的形状,基于量纲分析及正交设计理论,利用AUTODYN软件中SPH算法研究了EFP成型参数、弹靶材料参数对靶后破片云形状的影响,建立了EFP垂直侵彻靶后破片云形状的数学描述模型。利用该模型计算了EFP垂直侵彻靶后破片云形状参量长半轴,并和仿真结果及相关试验结果进行对比,结果表明,该模型计算的后效破片云长半轴结果与相关试验结果误差控制在3%以内,能够准确描述EFP垂直侵彻有限厚靶板后效破片云的形状。展开更多
为综合分析爆炸成型弹丸(explosively formed projectile,EFP)的构型对其气动特性和侵彻性能的影响,实现兼具良好气动特性和侵彻性能的EFP设计。开展了EFP的成型和飞行试验,在试验验证数值有效性的基础上,基于任意拉格朗日欧拉(arbitrar...为综合分析爆炸成型弹丸(explosively formed projectile,EFP)的构型对其气动特性和侵彻性能的影响,实现兼具良好气动特性和侵彻性能的EFP设计。开展了EFP的成型和飞行试验,在试验验证数值有效性的基础上,基于任意拉格朗日欧拉(arbitrary Lagrange-Euler,ALE)算法分析了后翻型EFP的三种典型构型(实心杆状、小空腔状、大空腔状)的成型过程及气动特性,并进一步开展了三种构型EFP侵彻半无限厚45#钢的数值模拟。结果表明:EFP小空腔结构提高了其飞行稳定性;空腔的增大降低了EFP的存速能力,实心、小空腔、大空腔三种构型的EFP炸高在1000倍弹径(30 m)时平均速度降分别为158 m/s,172 m/s,210 m/s;随着EFP空腔的增大,靶板开坑形貌由漏斗状逐渐转为等直径状。从工程实践角度设计EFP构型时:对于近距离目标应选取实心型;对于远距离目标应选取小空腔型。展开更多
基金supported by the Scientific and Technological Innovation Project(Grant No.KYGYZB0019003)。
文摘To quickly break through a reinforced concrete wall and meet the damage range requirements of rescuers entering the building,the combined damage characteristics of the reinforced concrete wall caused by EFP penetration and explosion shock wave were studied.Based on LS-DYNA finite element software and RHT model with modified parameters,a 3D large-scale numerical model was established for simulation analysis,and the rationality of the material model parameters and numerical simulation algorithm were verified.On this basis,the combined damage effect of EFP penetration and explosion shock wave on reinforced concrete wall was studied,the effect of steel bars on the penetration of EFP was highlighted,and the effect of impact positions on the damage of the reinforced concrete wall was also examined.The results reveal that the designed shaped charge can form a crater with a large diameter and high depth on the reinforced concrete wall.The average crater diameter is greater than 67 cm(5.58 times of charge diameter),and crater depth is greater than 22 cm(1.83 times of charge diameter).The failure of the reinforced concrete wall is mainly caused by EFP penetration.When only EFP penetration is considered,the average diameter and depth of the crater are 54.0 cm(4.50 times of charge diameter)and 23.7 cm(1.98 times of charge diameter),respectively.The effect of explosion shock wave on crater depth is not significant,resulting in a slight increase in crater depth.The average crater depth is 24.5 cm(2.04 times of charge diameter)when the explosion shock wave is considered.The effect of explosion shock wave on the crater diameter is obvious,which can aggravate the damage range of the crater,and the effect gradually decreases with the increase of standoff distance.Compared with the results for a plain concrete wall,the crater diameter and crater depth of the reinforced concrete wall are reduced by 5.94%and 9.96%,respectively.Compared to the case in which the steel bar is not hit,when the EFP hit one steel bar and the intersection of two steel bars,the crater diameter decreases by 1.36%and 5.45%respectively,the crater depth decreases by 4.92%and 14.02%respectively.The EFP will be split by steel bar during the penetration process,resulting in an irregular trajectory.
文摘采用LS-DYNA对在药型罩上粘附隔板结构形成带尾翼型爆炸成型弹丸(explosively formed projectile,EFP)进行三维数值模拟,从药型罩微元压跨速度和压力的角度初步探讨了形成尾翼型EFP的机理,对同一直径的大锥角型、球缺型和弧锥结合型药型罩形成的尾翼型EFP进行了对比分析,三种结构药型罩均能形成较为明显的尾翼,其中大锥角型药型罩得到的EFP速度最高。数值计算结果表明,EFP尾翼数与药型罩上所粘贴的隔板数一致,三种不同结构药型罩上粘贴四个隔板,得到的尾翼数均为四个。通过实验,对贴隔板法形成尾翼EFP做了进一步验证,实验结果与数值模拟结果基本一致。
文摘针对同一成型装药形成多模毁伤元问题,利用LS-DYNA动力有限元程序,采用流固耦合方法,对在药型罩前加装一刻槽圆环形成带尾翼爆炸成型弹丸(explosively formed projectile,EFP)的成型过程进行了数值模拟,结果表明,该装药结构能形成带有8个尾翼的EFP,带尾翼EFP的长径比是EFP长径比的2.75倍,其头部速度比EFP增加了15%,实现了带尾翼大长径比EFP和EFP两种模态的转换。
文摘由于规律性尾翼EFP(Explosively Formed Projectile)具有较好的飞行稳定性,为此对大炸高条件下EFP飞行稳定性进行研究。提出一种新型形成尾翼的简易方法,即在药型罩上粘附隔板,利用隔板改变爆轰波阵面的结构形状,从而改变药型罩的变形规律,形成一种带有尾翼的EFP。首先从理论上探讨了该方法的可行性,根据理论分析结果设计了不同尺寸的隔板。然后通过实验验证理论分析结果,最后采用LS-DYNA对尾翼EFP形成过程进行数值模拟。结果表明:在药型罩上粘贴隔板可以形成尾翼EFP,尾翼EFP形状与隔板尺寸具有一定的相关性。
文摘为了准确描述爆炸成型弹丸(Explosively Formed Projectile,EFP)垂直侵彻有限厚靶板后效破片云的形状,基于量纲分析及正交设计理论,利用AUTODYN软件中SPH算法研究了EFP成型参数、弹靶材料参数对靶后破片云形状的影响,建立了EFP垂直侵彻靶后破片云形状的数学描述模型。利用该模型计算了EFP垂直侵彻靶后破片云形状参量长半轴,并和仿真结果及相关试验结果进行对比,结果表明,该模型计算的后效破片云长半轴结果与相关试验结果误差控制在3%以内,能够准确描述EFP垂直侵彻有限厚靶板后效破片云的形状。
