Study On Gas Explosion Propagation Of Methane Spherical Tank Based On Numerical Simulation

According to statistics,from 2006 and 2015,a total of 12 hazardous chemical accidents occurred in China,they had caused 174 deaths,and an average of 14.5 deaths per accident.The frequent accidents,which cause serious damage to the chemical enterprise production safety and social stability and unity.From the data analysis,it can be seen that most of the hazardous chemical spillage and explosion accidents that cause a large number of casualties and economic losses occur during production and storage.Therefore,studying the explosion process of combustible gas represented by methane during its production and storage is of great significance for understanding the danger of explosion of methane and other combustible gases during production and storage.This paper uses FLACS software to simulate the conditions of the explosion pressure and velocity of the methane spherical tank under different working conditions and the flame propagation rules by setting different conditions of obstacles,different diameter leaks,and different ignition point locations.After the study,we found the following rules: 1.The presence of obstacles in the spherical tank will have an incentive effect on the propagation of the explosion flame.The more obstacles,the more pronounced the stretching process of the flame,and the explosion pressure peak with the obstacles in the spherical tank.As the number increases,the rate of pressure increase increases with the number of obstacles 2.When there is a leak at the bottom of the spherical tank,it will affect the maximum explosion pressure and pressure rise rate inside the spherical tank.The explosion pressure peak in the spherical tank will decrease as the diameter of the leak opening expands.3.The impact of the ignition point of different locations on the propagation of methane spherical tanks is: When the bottom is ignited,it can produce the maximum explosion pressure,the most obvious flame stretching,the fastest flame speed,but it also needs the longest time to reach the peak of explosion pressure.At the same time,according to the existing experimental platform of North China Institute of Science and Technology and the 20 L sealed spherical explosive device newly designed by North China University,an experimental model was prepared at a ratio of 1:50 000 and an explosion simulation experiment of a methane balloon tank was conducted.Different ignition position pairs were studied on how they can influence the explosion of methane spherical tank The study found that the numerical simulation results and the experimental simulation results obtained consistent conclusions on the change rule of the two sets of parameters in reaction time and explosive pressure rising rate.However,due to the existence of the scale effect,experimental results and numerical simulation results are only at the maximum explosion pressure is slightly biased.