Influence of the Cavity Structure in the Excavation Roadway on the Gas Explosion Characteristics

[Image: see text] Gas explosion accidents are one of the most severe coal mine disasters. Usually, they can cause considerable property losses and casualties, which seriously restrict the development of the coal mining industry. This study used Ansys/Fluent software to simulate gas explosions in excavation roadways with different cavity structures, and 11 models with different cavity structures were established. The study results show that the propagation law of gas explosion in an excavation roadway with different cavity structures was affected by the cavity shapes, the oval cavity of the long axis/short axis ratio (LA/SA), and the cavity numbers. The overpressure, impulse, and flame speed decreased when a cavity existed, compared to the values in a tube without a cavity. The values of overpressure, impulse, and flame speed were smallest in a rectangular cavity. Furthermore, with increasing the LA/SA, the strength of the gas explosion was reduced significantly. The more the cavities were, the better the intensity of gas explosions was controlled. The research results can provide theoretical support and an experimental basis for preventing and controlling gas explosion accidents.