Development of crack surface tracking algorithm for explosive fracture simulation with three-dimensional numerical manifold method

The enduring conflict between enhancing energy and ensuring safety stands as a principal obstacle in the development of high-energy explosives. As military weaponry technology advances, the demand for explosive safety has become increasingly critical. A key factor impacting the safety of explosives is the presence of internal cracks, which can significantly affect their performance and reliability in practical applications. Given the complexity and high costs associated with explosive testing, this study capitalizes on the strengths of the Numerical Manifold Method (NMM) for analyzing discontinuous deformations, and introduces an efficient fracture algorithm for accurately predicting crack surface propagation. In this algorithm, we utilize the maximum principal stress criterion to identify potential failure sites, employ a wave-pattern tracking method to construct the new crack surfaces, and refine them through a rigorous process of triangulation. The effectiveness and accuracy of this novel algorithm were validated through the analysis of four distinct fracture examples featuring pre-existing cracks. Simulation results demonstrate that within the framework of the 3DNMM, the proposed fracture algorithm successfully predicts the paths of crack propagation in explosives. This method provides essential analytical support for the design and evaluation of explosives, making a significant contribution to the advancement of the explosive safety technology.