Analysis of numerical calculation of elastic-plastic shell collapse with growing instability

Abstract

The paper presents research of the collapse of the elastic-plastic shell under external surface forces simulating explosive loading by mathematical simulation using numerical methods. The problem was solved in two-dimensional curved geometries as a non-stationary problem of continuum mechanics. We applied the Wilkins Lagrangian method. The instability of the shell was initiated by harmonic surface perturbations on the outer or inner surfaces. The characteristics of the explosive loading were also changed: the maximum pressure, pressure fall time constant, and the time of application of the explosive load. The size of instability was determined by the deviation of the disturbed surface or the boundary of the jet-forming layer from the cylindrical one. We have established the parameters of the shell and the impulse loading on the shell, which affect most strongly the growth of instability during collapse.