The numerical simulation for the process of shaped charge jet produced with the shell of explosives is performed by means of the ANSYS/LS-DYNA 3D software. The effect of warhead shell on shaped charge jet velocity has...The numerical simulation for the process of shaped charge jet produced with the shell of explosives is performed by means of the ANSYS/LS-DYNA 3D software. The effect of warhead shell on shaped charge jet velocity has been analyzed qualitatively in this paper. The numerical simulation results are creditable and in agreement well with that of the corresponding experiment. The research results show that the jet velocity of explosive with metal shell is higher than that without shell; when the shell thickness increases, jet＇ s head speed also increases; when the shell thickness increased to certain value, the jet velocity will not change any longer; with the same shell thickness, the bigger material density the higher jet＇s head velocity.展开更多
Research on the expansion and fracture of explosively driven metal shells has been a key issue in weapon development and structural protection.It is important to study and predict the failure mode,fracture mechanism,a...Research on the expansion and fracture of explosively driven metal shells has been a key issue in weapon development and structural protection.It is important to study and predict the failure mode,fracture mechanism,and fragment distribution characteristics of explosively driven metal shells.In this study,we used the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method and the fluid-structure interaction method to perform a three-dimensional numerical simulation of the expansion and fracture of a metal cylindrical shell.Our method combined the advantages of the FEM and SPH,avoiding system mass loss,energy loss,and element distortion;in addition,the proposed method had a good simulation effect on the interaction between detonation waves and the cylindrical shell.The simulated detonation wave propagation,shell damage morphology,and fragment velocity distribution were in good agreement with theoretical and experimental results.We divided the fragments into three regions based on their shape characteristics.We analyzed the failure mode and formation process of fragments in different regions.The numerical results reproduced the phenomenon in which cracks initiated from the inner surface and extended to the outer surface of the cylindrical shell along the 45°or 135°shear direction.In addition,fragments composed of elements are identified,and the mass and characteristic lengths of typical fragments at a stable time are provided.Furthermore,the mass and size distribution characteristics of the fragments were explored,and the variation in the fitting results of the classical distribution function under different explosion pressures was examined.Finally,based on mathematical derivation,the distribution formula of fragment velocity was improved.The improved formula provided higher accuracy and could be used to analyze any metal cylindrical shells with different length-to-diameter ratios.展开更多
文摘The numerical simulation for the process of shaped charge jet produced with the shell of explosives is performed by means of the ANSYS/LS-DYNA 3D software. The effect of warhead shell on shaped charge jet velocity has been analyzed qualitatively in this paper. The numerical simulation results are creditable and in agreement well with that of the corresponding experiment. The research results show that the jet velocity of explosive with metal shell is higher than that without shell; when the shell thickness increases, jet＇ s head speed also increases; when the shell thickness increased to certain value, the jet velocity will not change any longer; with the same shell thickness, the bigger material density the higher jet＇s head velocity.
基金supported by the National Natural Science Foundation of China(Grant No.11872118,11627901)。
文摘Research on the expansion and fracture of explosively driven metal shells has been a key issue in weapon development and structural protection.It is important to study and predict the failure mode,fracture mechanism,and fragment distribution characteristics of explosively driven metal shells.In this study,we used the finite element-smoothed particle hydrodynamics(FE-SPH)adaptive method and the fluid-structure interaction method to perform a three-dimensional numerical simulation of the expansion and fracture of a metal cylindrical shell.Our method combined the advantages of the FEM and SPH,avoiding system mass loss,energy loss,and element distortion;in addition,the proposed method had a good simulation effect on the interaction between detonation waves and the cylindrical shell.The simulated detonation wave propagation,shell damage morphology,and fragment velocity distribution were in good agreement with theoretical and experimental results.We divided the fragments into three regions based on their shape characteristics.We analyzed the failure mode and formation process of fragments in different regions.The numerical results reproduced the phenomenon in which cracks initiated from the inner surface and extended to the outer surface of the cylindrical shell along the 45°or 135°shear direction.In addition,fragments composed of elements are identified,and the mass and characteristic lengths of typical fragments at a stable time are provided.Furthermore,the mass and size distribution characteristics of the fragments were explored,and the variation in the fitting results of the classical distribution function under different explosion pressures was examined.Finally,based on mathematical derivation,the distribution formula of fragment velocity was improved.The improved formula provided higher accuracy and could be used to analyze any metal cylindrical shells with different length-to-diameter ratios.
