Papers by Keyword: Shaped Charge

Abstract: Based on the AUTODYN-2D nonlinear dynamics platform, numerical simulations andexperiments are conducted to study the effect of 44mm small-caliber shaped charge on penetrationcharacteristics. Copper as the suitable material is chosen for small-caliber shaped charges, and theinfluence of the cone and the thickness of liner on the penetration of the jet into the steel target isobtained. The results show that the penetration depth decreases with the growth of the cone angle.Moreover, with the thickness of liner increasing, the penetration depth increases first and thendecreases. Based on the numerical simulation, structural parameters of the double cone liners wereoptimized: the optimum thickness liner was 1.2mm, and the optimal upper and lower cone of thedouble-cone liner was 40° and 60°. Besides, a static explosion test that the optimized double coneof the copper-type liner penetrated 45# steel targets is performed to verify the numerical simulation.

Abstract: In the area of terrorism, there are many methods of attack. Among the most destruction it includes the use of IEDs. IED equipment is placed or made improvised way in which the active substance is explosive. The explosive is usually located either in bulk or in metal packaging (tube or artillery shell). When an explosion occurs in addition to standard effects such as explosion explosive pressure wave seismic wave and sound wave and shrapnel from explosives packaging. The comprehensive safety assessment is therefore necessary to take into account the greatest perimeter threat. It means to assess the size of the pressure shock wave range missile fragments and their energies mainly with regard to living organisms. In my work I have tried to create a set of formulas and graphs on a comprehensive assessment of potential threats to all kinds of events arising from the explosion of pipe bomb.

Abstract: The simulation and experimental studies of the Jets obtained from different conical liners from a charge having 56mm-diameter is presented in this paper. An OFHC copper liner of thickness 1 mm and 54 mm-diameters is used for jet formation analysis. Charge ignition is made by using Point detonation method. The simulation results are obtained from Ansysis Autodyn 2-D hydrocode. Experiments are conducted for a charge having 60⁰ conical liner. Flash X-ray Radiography is used for image capturing. The performance capacity of standard shaped charge is predicted by its penetration against steel target. It is observed that kinetic energy of the jet decreases as angle increases, also total energy of the explosive increases and hence the Ratio of the K.E of the jet to the total energy of the explosive decreases as the angle increases. Simulation results are compared with the experimental results. It is observed that simulation results are in favorable agreement within acceptable range of error with the experimental results.

Abstract: Under the pulse current, the lateral electromagnetic force on the shaped charge jet in the passive electromagnetic protective device is analyzed. Based on the equivalent circuit model, the current distribution model of metal plate is established according to the characteristic of current distribution proposed by Hummer. The lateral transient action model of a shaped charge jet is established based on the Biot Savart law. It is discussed in detail that the magnetic induction B_y of the shaped charge jet between two metal plates and the lateral electromagnetic force f_x on the shaped charge jet varies with time and location. B_y shows U distribution along the jet axial. Before the 37μs, f_x along the jet axial basically is M distribution; the maximum electromagnetic force appears in the distance near the site of the metal plates. After the 37μs, the lateral electromagnetic force along the jet axial basically is U distribution. Prior to 25μs, the total electromagnetic force F_x on the jet is approximately linear increase. In 25μ to 60μs, F_x maintains at a high level. The simulation result is identical with P. Appelgren’s result of static electrically-exploded conductors experiment.

Abstract: Jets obtained from shaped charge at different cone angle are simulated using Euler solver in Autodyn-2D Hydrocode against a 56mm-diameter of the charge. An OFHC copper liner of thickness 0.8mm and 54 mm-diameters is used for jet formation analysis. Point detonation method is used for Charge ignition. The simulation results are presented at 30 micro-second after initiation. Energy behavior is predicted at different obliquities. Numerical simulations are compared with the existing experimental results for liner angle 60. The depth of penetration and volume of the crater produced is measured. It is observed that simulation results are in good agreement with the experimental results. Flash X-ray Radiography was used for image capturing. It is observed that kinetic energy of the jet decreases as angle increases, also total energy of the explosive increases and hence the Ratio of the K.E of the jet to the total energy of the explosive decreases as the angle increases. The volume of the crater produced in steel at 65° has the highest value among the jets considered, so it can be used in oil well perforation also.

Abstract: A new design of shaped charges with a complex cumulative casing was proposed. The casing consists of two parts: conical and spherical. Mathematical modeling is conducted to determine the optimum shape of the cumulative casing. The feasibility of increasing the inlet area formed at detonation of the proposed shaped charge up to 2.8 times has been demonstrated.

Abstract: In this work, the shaped charge jet formation depends on different parameters which can has effect on jet behavior such as jet velocity, breakup and penetration. Jet radius or liner thickness, shell thickness, liner material density, α angle and stand-off distance are evaluated in purpose to investigate their effect on performance of shaped charge jet velocity and jet breakup phenomena, also we investigate the effect of stand-off distance on shaped charge jet penetration into steel target. We also studied the performance of some protective shields materials in order to assure more protection for vehicle structure against shaped charge jet penetration. For that, different materials were used as armors such as: kevlar epoxy, polyethylene, glass epoxy, steel-1006 and Al₂O₃ ceramic. These protective shields were evaluated in order to show their performance against shaped charge penetration into target. To do so, adopted explicit dynamic analyzing program Autodyn basing on finite element were used to simulate shaped charge jet formation and penetration. Autodyn-2D simulationshighlight the efficiency of our work comparing with the experiments done in literature and Birkhoff’s theory. In other terms, increasing in shell thickness, alpha angle and liner densityenhance jet breakup time, protective shields layered armor of steel-1006, steel 1006 with polyethylene and steel-1006 with Al₂O₃ceramic give more protection for structure against shaped charge jet penetration comparing with others armors.

Abstract: For avoid the perforation accident, oil perforating urgent need to calculate accurately shaped charge detonation parameters to guide the design and construction of perforation. According to the charge type and characteristics of shaped charge, based on traditional detonation theory and detonation parameters calculated method, this paper first determining shaped explosive detonation reaction equation, then analysis the shaped charge detonation heat, detonation temperature, detonation tolerance and detonation pressure and detonating velocity, extract the analytical methods of shaped charges detonation parameters suitable for oil at last. The specific practices: determined the reaction equation of shaped charges explosive with a maximum heat release rule; determined detonation heat, detonation temperature and detonation tolerance with law of Hess, internal energy value method and Avogadro law; calculated detonation velocity and pressure by Kamlet law; use engineering calculation method to analyze the detonating velocity as to the non-C-H-N-O composition shaped charges which containing feeling agent, bonding agent, flammable agent, plasticizer and other active agent; by revision Kamlet formula, get detonation pressure calculation formula.

Abstract: A set of 18 armour steel plates were stacked on top of each other and subjected to shape charges that went through the plates and created a hole that decreased in diameter as it went through consecutive plates. Afterwards, the plates were examined and the hardness near the hole and away from the hole was taken to determine the effect of the passing of the shaped charge through the plates. Also, specimens from the walls of the holes were taken to determine changes in the microstructure due to the shock wave and the resulting excessive heating from the shape charge. It was observed that the shock wave produced significant changes in the microstructure resulting in the appearance adiabatic shear bands (ASBs). These ASBs persisted in holes in plates placed further down the stack (up to 8^th in the stack). More complex microstructural mechanisms are thought to take place as opposed to erosion from the flow of the molten metal through the holes in the plates.

Abstract: According to the characteristics of the Yellow River ice flood, the author using LS-DYNA numerical simulation and shaped charge technology to research the 20cm thick ice failure characteristics when a certain amount of TNT exploded underwater, analysis the result and get the best explosive blasting point, and compared the numerical simulation results with experimental results, to verify the reliability of the numerical simulation, the results may guide the research of the ice-breaking equipment that based on shaped charge technology.