Reactive Flow Modeling of the Enhanced Corner Turning Test

The Enhanced Corner Turning (ECOT) test was designed to characterize the relative sensitivity of insensitive high explosive (IHE) materials. In this test, a steady detonation wave propagates from a long cylinder of donor explosive into a larger acceptor cylindrical charge. As the detonation wave transitions into the acceptor it must turn an abrupt corner. Sustaining a detonation during this shock diffraction is difficult for IHE due to the slower reactions and results in a region of partially reacted or unreacted HE (i.e. the dead zone). The ECOT test is specifically designed to be highly sensitive to geometric and material parameters, in particular the explosive lot and initial density. This work investigates the ability of reactive flow models, such as the Arrhenius Wescott-Stewart-Davis (AWSD) and Scaled Unified Reactive Front (SURF) models, to predict corner turning observed in experiments. The numerical simulations are challenging as results are sensitive to mesh resolution, artificial viscosity, choice of confinement material, and other modeling choices. Two different arbitrary Lagrangian-Eulerian (ALE) mesh strategies were evaluated to find a balance between accuracy and computation cost. Additionally, lot-specific calibrations for the AWSD model are explored to determine the sensitivity of the corner-turning behavior to rate parameters