Coupling mechanism of physical processes and chemical reactions during phase transition in liquid tanks under thermal radiation

This study addresses one of the knowledge gaps in liquid tank safety, i.e., the assessment of the coupling hazards between physical processes and chemical reactions in liquid tanks under transient high temperatures. If the phase transition process of the liquid storage tank occurs simultaneously with a gaseous explosion, a significantly more intense energy release will be generated within the tank. However, due to the challenges of numerical calculations and the complexities of experimental design, current research has yet to explore the potential hazards associated with the explosion of vapor and air within liquid storage tanks. A novel numerical model has been established to simulate the coupled processes of phase transitions and chemical reactions in this research. The findings indicate that phase transition and chemical reactions commence at the intersection of the two-phase interfaces and the tank walls. After the cessation of transient high temperature, the upward trend in pressure and temperature within the tank will persist for a certain duration. As the radiation temperature rises and the duration extends, phase transition and chemical reactions within the liquid tank occur increasingly earlier. The duration of the chemical reactions decreases as the radiation temperature increases and the duration extends; however, the molar concentration of reactants consumed during the reaction does not exhibit a monotonic change. The intersection of the high-temperature hazard zone and the premixed hazard zone, where both ignition energy and concentration conditions are met, can lead to intense chemical reactions. As the radiation temperature rises, the ignition energy also increases; however, this leads to greater instability in the premixed hazard zone, thereby increasing the likelihood of secondary explosions.