Effects of Cross-Section Shapes on Methane/air Mixture Explosion Characteristic Parameters in the Semi-Closed Pipeline Laying Space

The Eddy Dissipation Concept (EDC) model in FLACS software is used to analyze the influence of three different cross-sectional shapes on explosion process parameters in a semi-closed pipeline laying space. The following nine aspects are analyzed: promotion of overpressure wave, promotion of expansion flame front, flame promotion of distance, promotion of expansion flame front, flame promotion of speed, maximum overpressure of pipe, maximum temperature of flame, maximum combustion rate of gas, and maximum velocity of flame. The results indicate that under the methane concentrations and laying space sizes studied in this article, the explosion consequences caused by methane/air mixture in circular cross-sectional laying space are the most severe, followed by circular-rectangular cross-sectional laying space. The impact of laying space on rectangular cross-sections is the minimum. From the perspective of explosion consequences, the rectangle can be prioritized for the laying space shape of pipelines used for maintenance and repair. During the process of explosion accidents, it can effectively reduce the degree of injury to operators in the pipeline laying space.