Propagation Characteristics of Natural Gas Explosions at Different Ignition Positions in Complex H-Pipelines

AbstractIn order to investigate the propagation characteristics of natural gas explosions by ignition position in complex pipelines, a series of ignition positions were set up in an H-type pipeline for simulation using commercially available software. The findings of the study indicated that in the H-type pipeline contact pipe, the flame structure array develops with the greatest rapidity and the most violent shock wave propagation speed. The shock wave generated by the natural gas explosion is reflected and superimposed on multiple occasions when it encounters the pipeline wall, and it exhibits fluctuations and an increase in amplitude during propagation. In this process, the pressure peak is typically situated in closer proximity to the closed end of the pipeline, in comparison with the contact pipeline. The overpressure peak of the main pipeline was also observed to be higher. By comparing the rate of pressure rise at varying ignition locations and integrating this with the explosion hazard factor, it can be determined that the closer the ignition point, the greater the associated hazard. Consequently, the closed end of the pipeline was observed to experience a more significant degree of explosion hazard.