Author(s): Nathaniel Adams
Mentor(s): Clint Guymon
Institution BYU
Hazard Division (HD) 1.3 materials are primarily composed of energetic compounds with low detonation sensitivity. Due to these properties, they are typically assessed for safety using heat flux effects as the sole metric. However, incidents have revealed that when ignited under conditions where venting is not adequate, HD 1.3 materials can produce explosive overpressure effects in addition to the anticipated fire plumes. These unexpected explosions have led to structural damage and injuries, underscoring the limitations of using heat flux as the sole safety metric when performing safety assessments for potential HD 1.3 events. To address the need to understand HD 1.3 hazards, this research introduces a modeling approach to better predict the overpressure effects of HD 1.3 events. Termed the "bubble dynamics" model, this approach simulates the interaction of confined spheres, or “bubbles”, of gasses. Using this model, HD 1.3 explosion events can be simulated by applying a known pressure corresponding to the failure pressure of a structure containing HD 1.3 material. The “bubbles” are then allowed to interact and the transfer of pressure, temperature, and other properties between “bubbles” are simulated spatially and temporally. This model is then compared to experimental results to validate its accuracy in predicting overpressure effects. Preliminary findings indicate that this model can effectively anticipate overpressure effects including pressure dropoff time, pressure rise time, max pressure, and impulse at given distances. This offers a tool that will aid in enhancing safety assessments for HD 1.3 materials. This predictive capability aims to support more comprehensive safety guidelines and mitigation strategies for facilities handling HD 1.3 materials.