The disturbance of flat and V-shaped sandwich reactive armor configurations to shaped-charge jet is studied by a numerical approach. The disturbing and cutting effects of the two reactive armor configurations to the j...The disturbance of flat and V-shaped sandwich reactive armor configurations to shaped-charge jet is studied by a numerical approach. The disturbing and cutting effects of the two reactive armor configurations to the jet are successfully captured. The predicted disturbance characteristics and patterns are in fairly good agreement with the X-ray photographic observations. The residual depth of penetration into a semiinfinitive homogeneous steel target behind the reactive armor is computed for a series of jet/armor parameters. For the flat configuration, it is demonstrated that the residual penetration depth is not significantly reduced for a normal impact while it is reduced up to 75% for an oblique impact. In comparison, the V-shaped configuration reduces the penetration depth of the jet to 90%, and it is observed that the penetration depth is not sensitive to the V-shaped angle.展开更多
Explosive Reactive Armor was originally modeled under the assumption that the plates in the cassettes were very thin.Hence their thickness could be ignored,and the thicknesses of the plates were considered only based ...Explosive Reactive Armor was originally modeled under the assumption that the plates in the cassettes were very thin.Hence their thickness could be ignored,and the thicknesses of the plates were considered only based on their areal mass density.In particular,it was assumed that the jet-plate interaction was controlled by the plates to jet-mass-flux ratio criteria for a specific jet velocity and diameter.In the present study,we extended this analysis,examining the effect of the variation of the mass-flux along the jet on the disruption effect by the two plates.In addition,we examined the thickness effect of the plates on the plate's effectiveness,replacing the steel plates by low-density materials like aluminum and polycarbonate.The mass-flux model was adjusted to account for the plate-thickness effect.It was found that increasing the thickness of the plate,keeping the areal weight unchanged,slightly increases the overall effectiveness of the cassette,in particular by the forward moving plate interacting with the center and the slow parts of the jet.展开更多
The experimental research on protection capability of the flying-whip multifunctional explosive reactive armor (ERA) was performed, in which the comparison experiment was made on the damage effect of the flying-whip&#...The experimental research on protection capability of the flying-whip multifunctional explosive reactive armor (ERA) was performed, in which the comparison experiment was made on the damage effect of the flying-whip's geometrical figuration, material property and driven velocity on the long-rod armor-piercing-projectile. The moving velocity of the flying-whip driven by different explosives and the pressure attenuation law of shock wave travelling in the back plate were measured respectively with the electric probe method and the manganin piezoresistive gauge technique. The following conclusions based on a great quantity of experimental data were drawn: compared with the sandwich ERA the flying-whip multifunctional ERA has very good protection function against the long-rod armor-piercing-projectile, the shaped charge warhead and the anti-armor tandem warhead. In addition, the composite plate made of the armor-steel and rubber plate can lessen the vibration and shock of the main armor caused by the explosion of the charge..展开更多
Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge jets.Considering mobility,the...Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge jets.Considering mobility,the aim is to design a protection system with a minimal amount of required mass.The efficiency of an ERA is sensitive to the impact position and the timing of the detonation.Therefore,different designs have to be tested for several impact scenarios to identify the best design.Since analytical models are not predicting the behavior of the ERA accurately enough and experiments,as well as numerical simulations,are too time-consuming,a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed here.The ground truth for the artificial neural network(ANN)is numerical simulation results that are validated with experiments.The ANN approximates the plate positions for different materials,plate sizes,and detonation point positions with sufficient accuracy in real-time.In a future investigation,the results from the model can be used to estimate the interaction of the ERA with a given threat.Then,a measure for the effectiveness of an ERA can be calculated.Finally,an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.展开更多
There are two interaction mechanisms between shaped charge jet and thin flying plate driven by explosion, that is, the intermittent and continuous disturbance. Determination of the transition criteria for the intermit...There are two interaction mechanisms between shaped charge jet and thin flying plate driven by explosion, that is, the intermittent and continuous disturbance. Determination of the transition criteria for the intermittent and continuous disturbance is of importance for the penetration calculation of the escaping jet and the design of ERA(explosive reactive armour). In this paper a new criteria was presented based on the analysis of interaction process, and the effects of NATO angle and thickness of flying plate on the disturbance frequency were discussed. It is shown that the critical shaped charge jet velocity increases with the plate thickness and NATO angle, especially increases drastically between 45° and 60°.展开更多
文摘The disturbance of flat and V-shaped sandwich reactive armor configurations to shaped-charge jet is studied by a numerical approach. The disturbing and cutting effects of the two reactive armor configurations to the jet are successfully captured. The predicted disturbance characteristics and patterns are in fairly good agreement with the X-ray photographic observations. The residual depth of penetration into a semiinfinitive homogeneous steel target behind the reactive armor is computed for a series of jet/armor parameters. For the flat configuration, it is demonstrated that the residual penetration depth is not significantly reduced for a normal impact while it is reduced up to 75% for an oblique impact. In comparison, the V-shaped configuration reduces the penetration depth of the jet to 90%, and it is observed that the penetration depth is not sensitive to the V-shaped angle.
文摘Explosive Reactive Armor was originally modeled under the assumption that the plates in the cassettes were very thin.Hence their thickness could be ignored,and the thicknesses of the plates were considered only based on their areal mass density.In particular,it was assumed that the jet-plate interaction was controlled by the plates to jet-mass-flux ratio criteria for a specific jet velocity and diameter.In the present study,we extended this analysis,examining the effect of the variation of the mass-flux along the jet on the disruption effect by the two plates.In addition,we examined the thickness effect of the plates on the plate's effectiveness,replacing the steel plates by low-density materials like aluminum and polycarbonate.The mass-flux model was adjusted to account for the plate-thickness effect.It was found that increasing the thickness of the plate,keeping the areal weight unchanged,slightly increases the overall effectiveness of the cassette,in particular by the forward moving plate interacting with the center and the slow parts of the jet.
文摘The experimental research on protection capability of the flying-whip multifunctional explosive reactive armor (ERA) was performed, in which the comparison experiment was made on the damage effect of the flying-whip's geometrical figuration, material property and driven velocity on the long-rod armor-piercing-projectile. The moving velocity of the flying-whip driven by different explosives and the pressure attenuation law of shock wave travelling in the back plate were measured respectively with the electric probe method and the manganin piezoresistive gauge technique. The following conclusions based on a great quantity of experimental data were drawn: compared with the sandwich ERA the flying-whip multifunctional ERA has very good protection function against the long-rod armor-piercing-projectile, the shaped charge warhead and the anti-armor tandem warhead. In addition, the composite plate made of the armor-steel and rubber plate can lessen the vibration and shock of the main armor caused by the explosion of the charge..
文摘Explosive reactive armor(ERA)is currently being actively developed as a protective system for mobile devices against ballistic threats such as kinetic energy penetrators and shaped-charge jets.Considering mobility,the aim is to design a protection system with a minimal amount of required mass.The efficiency of an ERA is sensitive to the impact position and the timing of the detonation.Therefore,different designs have to be tested for several impact scenarios to identify the best design.Since analytical models are not predicting the behavior of the ERA accurately enough and experiments,as well as numerical simulations,are too time-consuming,a data-driven model to estimate the displacements and deformation of plates of an ERA system is proposed here.The ground truth for the artificial neural network(ANN)is numerical simulation results that are validated with experiments.The ANN approximates the plate positions for different materials,plate sizes,and detonation point positions with sufficient accuracy in real-time.In a future investigation,the results from the model can be used to estimate the interaction of the ERA with a given threat.Then,a measure for the effectiveness of an ERA can be calculated.Finally,an optimal ERA can be designed and analyzed for any possible impact scenario in negligible time.
文摘There are two interaction mechanisms between shaped charge jet and thin flying plate driven by explosion, that is, the intermittent and continuous disturbance. Determination of the transition criteria for the intermittent and continuous disturbance is of importance for the penetration calculation of the escaping jet and the design of ERA(explosive reactive armour). In this paper a new criteria was presented based on the analysis of interaction process, and the effects of NATO angle and thickness of flying plate on the disturbance frequency were discussed. It is shown that the critical shaped charge jet velocity increases with the plate thickness and NATO angle, especially increases drastically between 45° and 60°.
文摘研究了HM X基钝感炸药的机械感度。根据测试结果初步确定了反应装甲的装药配方,最终装药配方由改变模拟反应装甲上、下板的材料和厚度以及穿甲弹与反应装甲法线的夹角,用反应起始装药的引爆效果确定。结果表明,钝感炸药的撞击感度、摩擦感度均随HM X粒度的减小而降低,随钝感剂含量的增加而降低;反应装甲的装药配方为HM X 97%、钝感剂3%。从理论上分析了炸药粒度变化对机械感度影响的机理,以及在穿甲弹参数和速度一定的条件下,反应装甲装药结构对冲击引爆的影响。
