Modeling of explosion dynamics in vessel-pipe systems to evaluate the performance of explosion isolation systems

Explosion isolation systems provide critical protection for interconnected vessels and work areas, preventing the spread of explosions through interconnecting pipes and ducts. These systems not only prevent propagating events, but also mitigate the elevated explosion hazards of interconnected vessels, related to pressure piling and enhanced turbulence. Explosion isolation systems can, however, fail catastrophically when they are not properly designed for a use case. Evaluating the performance of explosion isolation systems includes assessing their pressure resistance, flamebarrier efficacy, and determining appropriate installation distances, which typically requires extensive testing. To predict the performance of a system for use cases outside the tested conditions, models are needed to reliably predict both the explosion dynamics and the isolation system response. In this study, a physics-based model for explosion dynamics in vented vessel-pipe systems is developed and validated. An extensive series of large-scale validation experiments were conducted, including tests using an 8 m3 vessel with attached pipes, varying the pipe dimensions, ignition location, and mixture reactivity. The model accurately captures the effects of experimental parameters and predicts the time available for isolation systems to form a flame barrier. This model can help to predict installation distances and reduce the number of tests needed to comprehensively evaluate explosion isolation systems and their use cases.