Determination of the Jones-Wilking-Lee – Equation of state parameters from height-of-burst detonation tests using optimization method

Resumen

This work presents a practical and general methodology for determining Jones–Wilkins–Lee (JWL) Equation of State (EOS) parameters through numerical optimization, which is demonstrated here for the military explosive PG3 (similar to C4). The approach couples the Sequential with Domain Reduction strategy implemented in LS-OPT with a two-dimensional axisymmetric LS-DYNA model used to simulate height-of-burst spherical air-blast detonations. Three charge weights (0.7, 1.0, and 1.4 kg) were tested, with pressure sensors placed radially at 2, 4, and 8 meters. Pressure–time histories from the 2 m and 4 m sensors of the 0.7 kg and 1.4 kg tests were used for calibration, while the 1.0 kg case and 8 m sensors were left for validation.
The optimized JWL parameters reproduced the experimental overpressures in LS-DYNA with errors mostly below ± 10 %, accurately capturing both the shape and magnitude of the positive phase. These parameters were further validated using Viper::Blast software, achieving good agreement in peak pressures and impulses.
Overall, the study demonstrates a simple and cost-effective alternative to traditional methods, such as the cylinder test, for determining EOS parameters. By relying only on basic air blast tests and numerical optimization, the proposed methodology significantly reduces experimental complexity while maintaining high predictive accuracy, making it well suited for a wide range of blast modelling applications.