A new model has been defined that enables the estimation of the lethal radius(radius of efficiency)of HE(High Explosive)artillery projectiles against human targets.The model is made of several modules:CAD(Computer Aid...A new model has been defined that enables the estimation of the lethal radius(radius of efficiency)of HE(High Explosive)artillery projectiles against human targets.The model is made of several modules:CAD(Computer Aided Design)modeling,fragment mass distribution estimation,fragment initial velocity prediction,fragment trajectory calculation,effective fragment density estimation,and high explosive projectile lethal radius estimation.The results were compared with the experimental results obtained based on tests in the arena used in our country,and the agreement of the results was good.This model can be used in any terminal-ballistics scenario for high explosive projectiles since it is general,parametric,fast and relatively easy to implement.展开更多
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
To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test ...To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is established.According to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters.展开更多
Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is empl...Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor.展开更多
为认识爆炸成型弹丸(Explosively Formed Projectile,EFP)靶后破片在空气中自由飞散及侵彻验证板的时空分布演化规律,基于分形理论建立了考虑破片表面状况的侵彻接触面积计算公式,通过破片云离散化对靶后破片在验证板材料阻力下时空分...为认识爆炸成型弹丸(Explosively Formed Projectile,EFP)靶后破片在空气中自由飞散及侵彻验证板的时空分布演化规律,基于分形理论建立了考虑破片表面状况的侵彻接触面积计算公式,通过破片云离散化对靶后破片在验证板材料阻力下时空分布特性进行了研究,并结合多层验证木板回收试验,获得了不同飞散角区间内破片侵彻的平均停留位置空间分布。研究结果表明:靶板破片的径向飞散距离整体上大于EFP破片;当验证板等效阻应力小于临界阻应力,破片侵彻停留位置空间分布呈现出一定的椭球形状,靶后破片在空气中飞散空间分布与在验证板内侵彻停留位置空间分布可以通过不同验证板等效阻应力下时空分布相互转化;各飞散区间破片侵彻后平均停留位置的计算结果与试验结果变化趋势基本一致,解决了以往后效验证板试验只能获得破片数量而无法获得破片侵彻停留位置空间分布的问题,为靶后破片对装甲车辆的毁伤效能评估提供技术支持。展开更多
压环是爆炸成型弹丸(Explosively Formed Projectile,EFP)装药结构中紧固装药和药型罩不可缺少的部件。为研究其在爆炸驱动过程中对药型罩形成EFP特征的影响,选取典型球缺型紫铜药型罩基准装药结构,采用有限元分析软件的拉格朗日、任意...压环是爆炸成型弹丸(Explosively Formed Projectile,EFP)装药结构中紧固装药和药型罩不可缺少的部件。为研究其在爆炸驱动过程中对药型罩形成EFP特征的影响,选取典型球缺型紫铜药型罩基准装药结构,采用有限元分析软件的拉格朗日、任意拉格朗日-欧拉、光滑粒子流法(Smooth Particle Hydrodynamics,SPH)及有限元法(Finite Element Method,FEM)-SPH自适应耦合等算法分别建模和仿真计算,对各算法计算获得的EFP速度和形态特征与脉冲X光摄影拍摄的EFP图像进行对比,采用FEM-SPH算法获得高精度的EFP成型仿真结果。针对该基准装药结构,在压环与药型罩质量比M_(R)/M_(L)≤0.2范围,进行矩形及非矩形压环参数(如轴向、径向厚度及截面形状)和材料对EFP初速、质量转换比、长径比和气动特性(密实度及迎风面积)参数影响的仿真计算。研究结果表明:矩形截面压环的轴向、径向厚度及材料参数对EFP初速影响在3%以内;对EFP质量转换比呈递减趋势(最大可降低12.6%);对EFP长径比呈递减趋势(最大可降低19.2%);密实度呈递增趋势,钢环较无压环,EFP的密实度提高32.6%;迎风面积呈递减趋势。以上结果表明考虑压环有利于EFP翻转成型和形成更密实的杆式EFP,并减小其迎风阻力。所得研究结果可为EFP装药结构的优化设计提供指导。展开更多
Concrete material model plays an important role in numerical predictions of its dynamic responses subjected to projectile impact and charge explosion.Current concrete material models could be distinguished into two ki...Concrete material model plays an important role in numerical predictions of its dynamic responses subjected to projectile impact and charge explosion.Current concrete material models could be distinguished into two kinds,i.e.,the hydro-elastoplastic-damage model with independent equation of state and the cap-elastoplastic-damage model with continuous cap surface.The essential differences between the two kind models are vital for researchers to choose an appropriate kind of concrete material model for their concerned problems,while existing studies have contradictory conclusions.To resolve this issue,the constitutive theories of the two kinds of models are firstly overviewed.Then,the constitutive theories between the two kinds of models are comprehensively compared and the main similarities and differences are clarified,which are demonstrated by single element numerical examples.Finally,numerical predictions for projectile penetration and charge explosion experiments on concrete targets are compared to further demonstrate the conclusion made by constitutive comparison.It is found that both the two kind models could be used to simulate the dynamic responses of concrete under projectile impact and blast loadings,if the parameter needed in material models are well calibrated,although some discrepancies between them may exist.展开更多
文摘A new model has been defined that enables the estimation of the lethal radius(radius of efficiency)of HE(High Explosive)artillery projectiles against human targets.The model is made of several modules:CAD(Computer Aided Design)modeling,fragment mass distribution estimation,fragment initial velocity prediction,fragment trajectory calculation,effective fragment density estimation,and high explosive projectile lethal radius estimation.The results were compared with the experimental results obtained based on tests in the arena used in our country,and the agreement of the results was good.This model can be used in any terminal-ballistics scenario for high explosive projectiles since it is general,parametric,fast and relatively easy to implement.
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.
基金supported by Project of the National Natural Science Foundation of China (No.62073256, 61773305)the Key Science and Technology Program of Shaanxi Province (No.2020GY-125)Xi’an Science and Technology Innovation talent service enterprise project (No.2020KJRC0041)。
文摘To objectively obtain the three-dimensional coordinates of the projectile fuze proximity explosion when projectile intersects the head of missile target, we propose a dynamic seven photoelectric detection screen test method, which is made up of six plane detection screens and a flash photoelectric dynamic detection screen. The three-dimensional coordinates calculation model of the projectile proximity explosion position based on seven plane detection screens with dynamic characteristics is established.According to the relation of the dynamic seven photoelectric detection screen planes and the time values,the analytical function of the projectile proximity explosion position parameters under non-linear motion is derived. The projectile signal filtering method based on discrete wavelet transform is explored in this work. Additionally, the projectile signal recognition algorithm using an improved particle swarm is proposed. Based on the characteristics of the time duration and the signal peak error for the projectile passing through the detection screen, the signals attribution of the same projectile passing through six detection screens are analyzed for obtaining precise time values of the same projectile passing through the detection screens. On the basis of the projectile fuze proximity explosion test, the linear motion model and the proposed non-linear motion model are used to calculate and compare the same group of projectiles proximity explosion position parameters. The comparison of test results verifies that the proposed test method and calculation model in this work accurately obtain the actual projectile proximity explosion position parameters.
文摘Utilizing finite element analysis,the ballistic protection provided by a combination of perforated D-shaped and base armor plates,collectively referred to as radiator armor,is evaluated.ANSYS Explicit Dynamics is employed to simulate the ballistic impact of 7.62 mm armor-piercing projectiles on Aluminum AA5083-H116 and Steel Secure 500 armors,focusing on the evaluation of material deformation and penetration resistance at varying impact points.While the D-shaped armor plate is penetrated by the armor-piercing projectiles,the combination of the perforated D-shaped and base armor plates successfully halts penetration.A numerical model based on the finite element method is developed using software such as SolidWorks and ANSYS to analyze the interaction between radiator armor and bullet.The perforated design of radiator armor is to maintain airflow for radiator function,with hole sizes smaller than the bullet core diameter to protect radiator assemblies.Predictions are made regarding the brittle fracture resulting from the projectile core′s bending due to asymmetric impact,and the resulting fragments failed to penetrate the perforated base armor plate.Craters are formed on the surface of the perforated D-shaped armor plate due to the impact of projectile fragments.The numerical model accurately predicts hole growth and projectile penetration upon impact with the armor,demonstrating effective protection of the radiator assemblies by the radiator armor.
文摘为认识爆炸成型弹丸(Explosively Formed Projectile,EFP)靶后破片在空气中自由飞散及侵彻验证板的时空分布演化规律,基于分形理论建立了考虑破片表面状况的侵彻接触面积计算公式,通过破片云离散化对靶后破片在验证板材料阻力下时空分布特性进行了研究,并结合多层验证木板回收试验,获得了不同飞散角区间内破片侵彻的平均停留位置空间分布。研究结果表明:靶板破片的径向飞散距离整体上大于EFP破片;当验证板等效阻应力小于临界阻应力,破片侵彻停留位置空间分布呈现出一定的椭球形状,靶后破片在空气中飞散空间分布与在验证板内侵彻停留位置空间分布可以通过不同验证板等效阻应力下时空分布相互转化;各飞散区间破片侵彻后平均停留位置的计算结果与试验结果变化趋势基本一致,解决了以往后效验证板试验只能获得破片数量而无法获得破片侵彻停留位置空间分布的问题,为靶后破片对装甲车辆的毁伤效能评估提供技术支持。
文摘压环是爆炸成型弹丸(Explosively Formed Projectile,EFP)装药结构中紧固装药和药型罩不可缺少的部件。为研究其在爆炸驱动过程中对药型罩形成EFP特征的影响,选取典型球缺型紫铜药型罩基准装药结构,采用有限元分析软件的拉格朗日、任意拉格朗日-欧拉、光滑粒子流法(Smooth Particle Hydrodynamics,SPH)及有限元法(Finite Element Method,FEM)-SPH自适应耦合等算法分别建模和仿真计算,对各算法计算获得的EFP速度和形态特征与脉冲X光摄影拍摄的EFP图像进行对比,采用FEM-SPH算法获得高精度的EFP成型仿真结果。针对该基准装药结构,在压环与药型罩质量比M_(R)/M_(L)≤0.2范围,进行矩形及非矩形压环参数(如轴向、径向厚度及截面形状)和材料对EFP初速、质量转换比、长径比和气动特性(密实度及迎风面积)参数影响的仿真计算。研究结果表明:矩形截面压环的轴向、径向厚度及材料参数对EFP初速影响在3%以内;对EFP质量转换比呈递减趋势(最大可降低12.6%);对EFP长径比呈递减趋势(最大可降低19.2%);密实度呈递增趋势,钢环较无压环,EFP的密实度提高32.6%;迎风面积呈递减趋势。以上结果表明考虑压环有利于EFP翻转成型和形成更密实的杆式EFP,并减小其迎风阻力。所得研究结果可为EFP装药结构的优化设计提供指导。
基金supported by the National Natural Science Foundations of China (Grant Nos. 52178515, 52078133)
文摘Concrete material model plays an important role in numerical predictions of its dynamic responses subjected to projectile impact and charge explosion.Current concrete material models could be distinguished into two kinds,i.e.,the hydro-elastoplastic-damage model with independent equation of state and the cap-elastoplastic-damage model with continuous cap surface.The essential differences between the two kind models are vital for researchers to choose an appropriate kind of concrete material model for their concerned problems,while existing studies have contradictory conclusions.To resolve this issue,the constitutive theories of the two kinds of models are firstly overviewed.Then,the constitutive theories between the two kinds of models are comprehensively compared and the main similarities and differences are clarified,which are demonstrated by single element numerical examples.Finally,numerical predictions for projectile penetration and charge explosion experiments on concrete targets are compared to further demonstrate the conclusion made by constitutive comparison.It is found that both the two kind models could be used to simulate the dynamic responses of concrete under projectile impact and blast loadings,if the parameter needed in material models are well calibrated,although some discrepancies between them may exist.
