Study On The Effect Of Pipeline Structure On Explosion Prevention

Gas explosion is one of the main accidents in China’s coal mines.The high temperature and high pressure shock wave produced by gas explosion will cause great harm to production personnel,economic loss and bad social influence.How to eliminate the harmfulness of gas explosion and ensure the safety of production personnel is an important task to be solved urgently.The structure of coal mine shaft is complex,but the research on the influence of the change of pipeline structure on the propagation process of gas explosion is not sufficient,and there is still little research on the influence of the change of pipeline structure on the effect of internal explosion resistance.The influence of pipeline structure changes such as horizontal,right-angle,diameter change and angle change on gas explosion propagation process and explosion prevention process was studied.The results show that the flame propagation velocity of horizontal duct is faster in 0-3.0m,and the flame propagation velocity of right-angle duct is faster in 3.0-3.5m.The right-angle duct is more conducive to achieve detonation resistance,and the amount of ABC dry powder required for explosion prevention is reduced by 80%.The peak value of explosive overpressure in right-angle pipeline is larger,leading to the decrease of pressure gradient in the pipeline before right-angle turning,which reduces the flame propagation speed in the pipeline and promotes the explosion resistance process.The large increase of flame front area in right-angle pipe can also promote the detonation resistance process.Under the influence of a variety of effects,the amount of ABC dry powder required for explosion resistance in right-angle pipelines is greatly reduced.The change of the pipe structure has a significant effect on the gas explosion propagation and explosion prevention prograss.When the pipe diameter increases,the explosion overpressure peaks in the right-angle duct and the horizontal dcut both decrease;when the pipe diameter decreases,the explosion overpressure peaks increase.In the case of variable diameter,the amount of ABC dry powder required for explosion prevention in horizontal ducts is reduced compared to the case of constant diameter,and the amount of ABC dry powder required for explosion prevention in right-angle ducts is increased compared with the case of constant diameter,but the amount of ABC dry powder required for explosion prevention in right-angle ducts The amount of ABC dry powder required in the horizontal dcut is still more than 50% less than that in the right-angle duct.Compared with the 90° duct,the change of the pipeline angle will increase the pressure peak in the duct,and the time delay of the pressure peak will occur;the flame propagation speed will decrease after the pipeline angle changes.Compared with the 90° duct,the amount of ABC powder required for explosion prevention in the pipeline with other angles is greatly increased.Affected by the flame propagation speed of the pipeline,the further back the nozzle in the horizontal duct is,the greater the amount of ABC dry powder required.The amount of ABC dry powder required for explosion resistance at each position in the right-angle duct has no obvious change.The change of the pipeline structure has a great influence on the gas explosion propagation process and the explosion prevention process.The change of the pipeline structure reduces the propagation speed of the explosion flame,or the surface area of??the flame front increases greatly,which is conducive to promoting the explosion prevention process.By exploring the propagation law of gas explosion in pipelines with different structures,and finding more favorable conditions for blocking the explosion propagation process according to the law,it is of great significance to weaken the hazard of gas explosion.