Numerical simulation study on explosion characteristics of large vault tanks with different height-to-diameter ratios

Abstract

ABSTRACT This study employs Large Eddy Simulation (LES) to investigate the effects of the Height-to-Diameter (H/D) ratio on the explosion characteristics of gasoline-air mixtures in storage tanks, and the flow field, flame propagation velocity, and explosion overpressure were analyzed. The research shows that the dynamic change of the vortex in the tank is the key to the explosion oscillation, its generation accelerates the flame propagation, and its weakening inhibits the explosion. As the H/D ratio increases, the peak speed of flame propagation decreases, and when the H/D ratio increases from 0.5 to 0.9, the peak speed decreases by 200%. The study also reveals that with the decrease of H/D, both peak explosion overpressure and flame velocity increase. The maximum overpressure appears near the tank top, and when H/D is 0.5, the maximum overpressure of the tank top is 3.75 MPa. The simulation result shows that internal explosion pressures exceed the tanks’ design limits across all H/D ratios, which indicates that it is necessary to take reasonable pressure relief measures to prevent and control the explosion disaster of the vaulted tanks. The research results provide important theoretical and practical guidance for the safe design of storage tanks and the prevention of explosion accidents.