Study on characteristics of methane explosion suppression by N2-water mist gas-liquid two-phase coupling

To investigate the effect of N2-water mist gas-liquid two-phase coupling on the propagation of methane explosion flames, based on a self-made mesoscale shock wave pipeline, we investigate the effect of N2 at different injection pressures on the propagation of methane explosion flames, and visualize the flame propagation process of N2 and water mist at different injection positions by Fluent. The results show that the performance of N2 explosion suppression is closely related to its injection pressure. When sprayed pressure is 3.5 MPa , the flame propagation speed is greatly reduced, and the explosion begins to be suppressed. The N2 sprayed into the pipeline ito the pipeline is influenced by the flame movement and is mostly pushed downstream to mix with methane premixed gas, diluting methane concentration. N2 relative to water mist will first diffuse and dilute methane concentration, and then the two-phase coupling will suppress the acceleration mechanism of flame wave and pressure wave mutual promotion; the explosion suppression effect of water mist and N2 staggered injection is better than that of parallel injection and opposite injection.