LES evaluation of hydrogen explosion disaster in interconnected vessels

Abstract

Using the LES method, this study is aimed at evaluating the hydrogen explosion disaster in interconnected vessels. The flame evolution, flame front speed, explosion overpressure, vorticity and velocity vectors are obtained by changing volume ratio, pipe length, pipe diameter and ignition position. The result indicated that as the volume ratio increases, the flame vorticity decreases, resulting in a lower maximum flame front speed. However, due to stronger pre-compression, the maximum explosion overpressure increases. An increase in pipe diameter significantly reduces flame vorticity, leading to a reduction in both maximum flame front speed and maximum explosion overpressure. With increasing pipe length, the flame vorticity increases, and the maximum flame front speed exhibits a monotonic increase, while the maximum explosion overpressure follows a trend of “initially slightly decreasing, then remaining nearly constant.” The ignition in the smaller vessel resulted in the highest vorticity and flame front speed, followed by ignition in the big vessel, with the lowest flame front speed observed when the ignition occurred at the center of the pipe. The ignition in the big vessel produced the highest pre-compression and explosion overpressure, followed by ignition in the smaller vessel, with the lowest explosion overpressure observed when the ignition occurred at the center of the pipe.