With respect to the problems of that the shaped charge warhead currently uses a cover method to improve the penetration power, a method using an explosive network technology as the detonation mode of shaped charge war...With respect to the problems of that the shaped charge warhead currently uses a cover method to improve the penetration power, a method using an explosive network technology as the detonation mode of shaped charge warhead is proposed. In the context of some shaped charge warhead, a synchronous explosive network prototype is designed according to some charge structure parameters, such as the liner and main grain. From the performance comparison test, it can be known that the explosive network not only stably detonates, but also largely improves the penetration power and stability. Experimental results show that explosive network technology is an effective method for improving the penetration power. The results lay a solid foundation for the engineering application of the technology in the shaped charge warhead.展开更多
Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters ...Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.展开更多
On the basis of the theories of mechanics of explosive and rock fracture mechanics, the mechanism of crack initiation and its expansion of directional fracture controlled blasting with shaped charges in rock were stud...On the basis of the theories of mechanics of explosive and rock fracture mechanics, the mechanism of crack initiation and its expansion of directional fracture controlled blasting with shaped charges in rock were studied, then the blasting parameters were designed and tested by a model test in laboratory and field experiment. The experimental and test results showed that the energy from blasting is directionally concentrated for the cumulative action. The directional expansion of cracks is satisfactory, the results of the model test and field test suggested that the orientation fracture blasting with shaped charge is a good means of excavating tunnels or cutting rock.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
An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation vel...An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation velocity and the semi-empirical relationship of detonation pressure that both change with charge diameter and confinement condition are established.The detonation velocity and pressure of small charges are calculated and experimentally verified,and the detonation velocity deviation is less than 7% while the detonation pressure deviation is less than 9%.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
In order to study and apply the penetration performance of jetting penetrator charge at long stand-off distance, three jetting penetrator charges(JPC), including spherical cone liner, truncated wide-angle liner and sp...In order to study and apply the penetration performance of jetting penetrator charge at long stand-off distance, three jetting penetrator charges(JPC), including spherical cone liner, truncated wide-angle liner and spherical segment liner, are designed. The numerical simulation analysis of the formation, elongation and penetration processes of rod-like jet is conducted by using LS-DYNA software. And the penetrating test is carried out at long stand-off distance. The test results show that the rod-like jet formed by the optimized spherical segment liner can pierce through a 90mm thick 45# steel target at 20 charge diameters(CD) stand-off distance when the charge detonation mode is a central point initiation, and the penetration depth can be up to 1.6CD. It is concluded that, at 20 CD stand-off distance, the penetration performance of JPC with spherical segment liner is the best, that of truncated wide-angle liner takes second place, and that of spherical cone liner is the worst.展开更多
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
To further explore the damage characteristics and impact response of the shaped charge to the solid rocket engine(SRE) in storage or transportation, protective armor was designed and the shelled charges model(SCM)/SRE...To further explore the damage characteristics and impact response of the shaped charge to the solid rocket engine(SRE) in storage or transportation, protective armor was designed and the shelled charges model(SCM)/SRE with protective armor impacting by shaped charge tests were conducted. Air overpressures at 5 locations and axial acceleration caused by the explosion were measured, and the experimental results were compared with two air overpressure curves of propellant detonation obtained by related scholars. Afterwards, the finite element software AUTODYN was used to simulate the SCM impacted process and SRE detonation results. The penetration process and the formation cause of damage were analyzed. The detonation performance of TNT, reference propellant, and the propellant used in this experiment was compared. The axial acceleration caused by the explosion was also analyzed.By comprehensive comparison, the energy released by the detonation of this propellant is larger, and the HMX or Al particles contained in this propellant are more than the reference propellant, with a TNT equivalent of 1.168-1.196. Finally, advanced protection armor suggestions were proposed based on the theory of woven fabric rubber composite armor(WFRCA).展开更多
For shaped charges,LS-DYNA software was adopted to explore the influence of number of initiation points on the penetrator formation numerically.Changed the number of initiation points from 4 to 36,the performance of p...For shaped charges,LS-DYNA software was adopted to explore the influence of number of initiation points on the penetrator formation numerically.Changed the number of initiation points from 4 to 36,the performance of penetrator under four different kinds of typical charge diameter was analyzed,and the effect of detonation wave pressure on the liner was discussed.The minimum number of initiation points to substitute for annular initiation was obtained for each of four warheads with different charge diameters,and the curve representing the relation between the number of initiation points and charge diameter was found out also by using polynomial fitting.The simulation result provides a reference for the design of multimode warhead.展开更多
文摘With respect to the problems of that the shaped charge warhead currently uses a cover method to improve the penetration power, a method using an explosive network technology as the detonation mode of shaped charge warhead is proposed. In the context of some shaped charge warhead, a synchronous explosive network prototype is designed according to some charge structure parameters, such as the liner and main grain. From the performance comparison test, it can be known that the explosive network not only stably detonates, but also largely improves the penetration power and stability. Experimental results show that explosive network technology is an effective method for improving the penetration power. The results lay a solid foundation for the engineering application of the technology in the shaped charge warhead.
文摘Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.
文摘On the basis of the theories of mechanics of explosive and rock fracture mechanics, the mechanism of crack initiation and its expansion of directional fracture controlled blasting with shaped charges in rock were studied, then the blasting parameters were designed and tested by a model test in laboratory and field experiment. The experimental and test results showed that the energy from blasting is directionally concentrated for the cumulative action. The directional expansion of cracks is satisfactory, the results of the model test and field test suggested that the orientation fracture blasting with shaped charge is a good means of excavating tunnels or cutting rock.
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An expanding model of the confinement of non-ideal detonation of small charge is established on the basis of the nozzle theory.Making use of the expanding model,the analytic relationship of small charge detonation velocity and the semi-empirical relationship of detonation pressure that both change with charge diameter and confinement condition are established.The detonation velocity and pressure of small charges are calculated and experimentally verified,and the detonation velocity deviation is less than 7% while the detonation pressure deviation is less than 9%.
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In order to study and apply the penetration performance of jetting penetrator charge at long stand-off distance, three jetting penetrator charges(JPC), including spherical cone liner, truncated wide-angle liner and spherical segment liner, are designed. The numerical simulation analysis of the formation, elongation and penetration processes of rod-like jet is conducted by using LS-DYNA software. And the penetrating test is carried out at long stand-off distance. The test results show that the rod-like jet formed by the optimized spherical segment liner can pierce through a 90mm thick 45# steel target at 20 charge diameters(CD) stand-off distance when the charge detonation mode is a central point initiation, and the penetration depth can be up to 1.6CD. It is concluded that, at 20 CD stand-off distance, the penetration performance of JPC with spherical segment liner is the best, that of truncated wide-angle liner takes second place, and that of spherical cone liner is the worst.
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To further explore the damage characteristics and impact response of the shaped charge to the solid rocket engine(SRE) in storage or transportation, protective armor was designed and the shelled charges model(SCM)/SRE with protective armor impacting by shaped charge tests were conducted. Air overpressures at 5 locations and axial acceleration caused by the explosion were measured, and the experimental results were compared with two air overpressure curves of propellant detonation obtained by related scholars. Afterwards, the finite element software AUTODYN was used to simulate the SCM impacted process and SRE detonation results. The penetration process and the formation cause of damage were analyzed. The detonation performance of TNT, reference propellant, and the propellant used in this experiment was compared. The axial acceleration caused by the explosion was also analyzed.By comprehensive comparison, the energy released by the detonation of this propellant is larger, and the HMX or Al particles contained in this propellant are more than the reference propellant, with a TNT equivalent of 1.168-1.196. Finally, advanced protection armor suggestions were proposed based on the theory of woven fabric rubber composite armor(WFRCA).
文摘For shaped charges,LS-DYNA software was adopted to explore the influence of number of initiation points on the penetrator formation numerically.Changed the number of initiation points from 4 to 36,the performance of penetrator under four different kinds of typical charge diameter was analyzed,and the effect of detonation wave pressure on the liner was discussed.The minimum number of initiation points to substitute for annular initiation was obtained for each of four warheads with different charge diameters,and the curve representing the relation between the number of initiation points and charge diameter was found out also by using polynomial fitting.The simulation result provides a reference for the design of multimode warhead.
