Simulation of explosive fracture cylinder test using DYNA

Abstract
There is a great need in the area of dynamic fracture to develop precise validation tests which are simple, reproducible and provide a challenge to the simulation tools. One such test is the explosive fracture cylinder which comprises a cylinder of material (e.g. iron) with a small hole along the axis. The hole is filled with explosive and initiated at one end which results in a focussing of release waves at the other end of the cylinder to produce a fracture cone. By varying the length of the cylinder it is possible to either expel the cone or capture the conical crack at various points in its progression. Sectioning the cylinder thereby results in a detailed void growth pattern that can be studied and compared with simulation results. This paper describes a detailed comparison of the simulation with the experiments and discusses the influence of mesh size. shaw and explosive on the results. It is concluded that the Goldthorpe path Dependent Ductile Fracture Model represents a promising way forward for describing ductile fracture in continuum hydrocodes.