Dynamic Response and Damage Analysis of a Large Steel Tank Impacted by an Explosive Fragment

Abstract

The fragments generated by explosions of storage tanks in chemical industrial parks may cause perforations or dents in adjacent tanks and trigger a domino effect. This paper determined reasonable fragment parameters based on the statistical laws of accidents and empirical formulas. The dynamic response process of large steel tanks impacted by fragments was simulated with ls-dyna. The typical impact process and results were analyzed in detail, and the damage laws of the tanks were discussed under various filling coefficients, volumes, fragment velocities, and impact angles. The results indicate that the inertial resistance of the inner liquid shortens the impact duration. Multiple collisions occur between the fragment and tank during impact, and the impact process involves three stages: initial collision, crushing and collision, and separation flight. The impact center displacement shows a fast and then slow reduction trend as the liquid level height increases, and the damage to the tank is negatively correlated with the liquid level height. The damage is lower when the tank volume is larger in an empty tank or at a high liquid level, while the damage instead increases when the volume exceeds 5000 m3 at a low liquid level. The peak impact force of the end-cap fragment is greatest when frontal impact occurs. Fragment flipping and curling occur at 45 deg and 90 deg impact, respectively. As the vertical impact angle increases from 0 deg to 90 deg, the fragment impact mode changes from initial frontal impact to flip detachment and finally to curling deformation.