Dust raising law of gas explosion in a 3D reconstruction real tunnel: Based on ALE-DEM model

A method based on the combination of finite element and discrete element theories is proposed to reveal the dust raising law of gas explosion shockwaves in 3D reconstructed real tunnels. The influence of a real tunnel's wall structure on shock wave overpressure is simulated and explored, the mechanism of action of the gas explosion shock wave on coal dust particles is revealed. Results indicate Peak overpressure of the fluid near the uneven walls exceeds that at the center of the tunnel by up to 165%. The sharp increase in shock wave overpressure causes a rapid rise in coal dust. Simultaneously, coal dust can decrease the overpressure at the shock wave front by 6.3% to 34.6%. During the shock wave attenuation period, the ratio between the maximum rise height of coal dust and the total displacement decreases as the distance between coal dust and the explosion source increases.