Simulation study of flow field characteristics of gas explosion in low temperature environment

The methane has a high risk of gas explosion because its concentration has come into the explosion limit range in the liquefaction process of low-concentration oxygen-bed methane. This gas explosion process was simulated on a flow field platform at low temperature in an air tight container. According to the simulation results, when the reaction system volume and environmental pressure are invariable, the lower the ambient temperature, the greater the maximum explosion pressure, and the longer the time it takes the methane gas to reach the maximum explosion pressure; the explosion flow field set up the positive and negative flow areas with chemical reaction zone as the front, and continually approaching the wall; the flame propagation process as affected by the chemical reaction is a positive feedback mechanism, and four phases-flame ignition, accelerated propagation, attenuated propagation and quenching-are found occurring in the airtight container; with the falling down of the ambient temperature, flame propagation speed decreased markedly, and the flame duration extended. The resulting conclusions provide an important basis for understanding methane explosion mechanism and preventing explosion accidents in the liquefaction process of low-concentration oxygen-bed methane under low-temperature conditions.