On Implementation of Implosion Principle in Shaped Charges with Hemispherical Liners of Degressive Thickness

On the basis of numerical simulation within a twodimensional axisymmetric problem of continuum mechanics the study shows that transition from the constant thickness of hemispherical shaped-charge liners to degressive thickness (decreasing from top to the basis) makes it possible to essentially increase the velocity of the formed shaped-charge jets due to conditions for implementing the implosion principle (spherically symmetric convergence of liner material to the center). Copper was considered as material of liners. We compared parameters of shaped-charge jets from hemispherical liners to parameters of the jet formed by the modern typical shaped charge with copper conic liner which provides penetration depth into a steel target at the level of 10 diameters of the charge. To carry out the comparative analysis, we calculated mass and velocity distributions for shaped-charge jets by results of numerical simulation. The velocity of the jet's head part and its full mass acted as integrated indicators for comparative estimation of the shaped-charge jets limit length which defines the jets potential penetrability. Findings of the research show that use of hemispherical liners of degressive thickness in shaped charges makes it possible to form the shaped-charge jets whose head part velocity and penetrability are not inferior to the one of the jets formed by conic liners.

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