Etude expérimentale, numérique et CFD de l'onde de surpression en champ proche et la charge au sol résultant d'une explosion de type BLEVE ( Boiling Liquid Expanding Vapour Explosion)

A BLEVE, or Boiling Liquid Expanding Vapor Explosion, is a complex thermomechanical phenomenon that occurs when a pressure liquefied gas – such as propane, ammonia, or hydrogen – undergoes rapid phase change due to containment failure. This two-phase physical explosion can arise during severe accidents involving the storage, transportation, or handling of such pressurized substances. BLEVEs are particularly dangerous due to their sudden and violent nature, often resulting in human casualties and extensive property damage. Understanding the underlying mechanisms and associated hazards is therefore crucial to tackle and bridge knowledge gaps and enhance safety procedures.This thesis provides a comprehensive investigation of BLEVE phenomena through experimental, numerical, and computational approaches. The work focuses on key aspects of the explosion process, including near-field aerial shock overpressure, boiling dynamics, vessel rupture and opening behavior, and ground loading effects. A wide range of small-scale experiments (70) were done using aluminum tubes, varying parameters such as failure pressure, liquid fill level, and weakened length. These variations allowed for an in-depth analysis of BLEVE causes and the severity of its related hazards.The research introduces new knowledge on compressed liquid BLEVEs (100 % liquid full), and numerical correlations based on semi-empirical models to estimate the near-field shock overpressure and ground load forces. The work investigates the critical role of vessel opening dynamics on the hazard’s intensity and improves the definition of BLEVE, along with a clearer identification of the specific conditions under which it is likely to occur. High-speed imaging validated theoretical models and offered visual insights into the internal and external dynamics involved in a BLEVE. The study has investigated both internal and external dynamics of BLEVE events, especially the role of liquid and vapor phases, contributing new knowledge to the field. Furthermore, computational simulations enabled the analysis of internal fluid behavior and external blast propagation, not easily observable through experiments alone.The relevance of this research lies in its ability to not only confirm current knowledge but also to extend the understanding of BLEVE, which has direct applications to risk assessment and hazard mitigation.