Design Technique for Calculating Functional Parameters of a Rotating Shaped Charge with Preliminary Heated Liner

The paper considers a separate issue of the shaped charge functioning, i.e., functioning of a rotating charge under preliminary thermal action on its liner. Estimates of two oppositely directed factors are provided: 1) increase in the shaped-charge jet dynamic plasticity (limit elongation coefficient); 2) increase in the jet susceptibility to centrifugal destruction. These factors are activated by preliminary thermal action on the shaped charge liner in the jet heated in excess of usual parameters. The so-called "thermal" increase in the limit elongation coefficient was estimated using empirical and theoretical dependences of this value on the shaped-charge jet parameters, and on the characteristics of its material. Strength dependence on temperature was accepted as linearly decreasing. Centrifugal factor was estimated based on the law of kinetic moment conservation taking into consideration the gradient nature of stretching and, up to a certain point, the radial thinning of jet elements. The moment of centrifugal and strength forces relationship reaching the critical value was accepted as the beginning of the jet element centrifugal destruction. From this time moment the jet radial extension started. The law of decompaction of its enlarging part was taken from studies previously conducted by the authors. It was demonstrated that the two considered factors acting in the opposite directions in a jet were in compliance with each other ensuring optimal preliminary heating of the liner and penetration effect with a local maximum.