Численный анализ управляемой потери устойчивости пологих менисковых облицовок при высокоскоростном обжатии

Abstract

Experimental and analytical research methods of losses of stability of meniscal form liners at their high-speed deformation, i.e., collapse, by products of detonation of explosive have limited opportunities. They are caused by the complicated nature of liner thickness change to control the operated loss of stability --- folding, high-speed deformations of liners, intensive drop of pressure acting on them and some other features. The paper introduces an approach to numerical three-dimensional modeling of collapse of meniscal form liners with variable thickness in the circumferential direction in the area of their periphery, the modeling being carried out by the finite element method in Lagrange coordinate system in LS-DYNA software package. The study also shows the main stages of implementing this approach and describes the key parameters of the materials models used, as well as the type of the final element and mechanism of adaptive updating of the computational grid. By the method of numerical simulation, we found the main regularities of liners collapse and folding of the afterbody of high speed elements formed during the collapse of the liners. The results of numerical calculations are confirmed by experimental data. The studies done are of interest to specialists involved in the analysis of the loss of stability of various structures under dynamic loads, as well as to specialists in the field of explosion and impact physics.