关键词: 爆炸, 甲烷, 火焰传播速度, 超压, 障碍物, 动力学

Abstract:

Using methane as a representative gas, the effects of different hole types and different sizes of perforated obstacles on the explosive flame and pressure propagation of combustible gas were studied in a closed conduit of 10% methane. The study found that when the obstacle partition is set, the explosion overpressure slowly grows in front of the obstacle, and continues to increase by the obstacle, and rapidly decreases before reaching the blind plate. The flame propagation rate increases slowly first and falls before passing through the obstacle partition, and rises sharply to the maximum after passing through the opening. As the opening area of the obstacle partition is reduced, the jetting effect caused by the airflow is obviously enhanced, and the influence caused by the negative pressure suction is increased, which leads to a more uneven distribution of the overpressure before and after the obstacle, and the obstacle is separated. The flame propagation speed in front of the plate decreases. Under the same opening area, the maximum overpressure and flame propagation speed are affected by different hole types. When the flame passes through the perforated obstacle partition, the circular opening is more in line with the flame shape than the square opening and the regular triangular opening. The law of development, the inner circular hole is smaller than the square hole, the flame is more affected, the turbulence is more obvious, and the flame speed and pressure rise are more obvious. The maximum overpressure relationship of different hole types is P _triangle>P _square>P _round>P _empty, flame propagation speed relationship is v _triangle>v _square>v _round>v _empty.

Key words: explosions, methane, flame propagation speed, overpressure, obstacle, kinetics