This study numerically investigated the effect of a very low gas concentration on a gas explosion's performance numerically using OpenFOAM. The use of the Harten–Lax–van Leer–Contact (HLLC) approximation algorithm based on the density-based solver was proposed to capture the shock wave. The process variable in XiFOAM of the OpenFOAM toolbox was used for the deflagration reaction. A gas explosion test was performed, and the numerical model with OpenFOAM was validated using the testing data. Based on the numerical investigation, the influence of a very low methane concentration on the flame and shock wave propagation law of a gas explosion was analyzed. It showed that the flame initially accelerated, followed by deceleration, and then accelerated again before slowing down. An increase in the methane concentration had an enhanced effect on the maximum overpressure ratio, which increased linearly with an increase in the methane concentration from 0 vol. % to 3.0 vol. % in the return tunnels. Increasing the explosive methane volume and concentration caused a significant increase in the flame spread distance. It was also noted that increasing the methane concentration caused a linear increase in the maximum overpressure ratio, and the methane volume and concentration both had a sensitive effects on the maximum overpressure ratio and average overpressure rising rate. The results clarified how the gas explosion law was affected by a very low gas concentration and provided theoretical support for controlling gas explosion disasters.

本研究使用 OpenFOAM 数值研究了非常低的气体浓度对气体爆炸性能的影响。建议使用基于密度求解器的 Harten-Lax-van Leer-Contact (HLLC) 近似算法来捕获冲击波。OpenFOAM 工具箱的 XiFOAM 中的过程变量用于爆燃反应。进行了气体爆炸测试，并使用测试数据验证了 OpenFOAM 的数值模型。在数值研究的基础上，分析了极低甲烷浓度对瓦斯爆炸火焰和冲击波传播规律的影响。它表明火焰最初加速，然后减速，然后再次加速，然后减速。甲烷浓度的增加对最大超压比的影响增强，随着甲烷浓度从 0 vol. 增加而线性增加。% 至 3.0 vol. % 在返回隧道中。增加爆炸性甲烷体积和浓度导致火焰传播距离显着增加。还注意到增加甲烷浓度导致最大超压比线性增加，甲烷体积和浓度均对最大超压比和平均超压上升速率有敏感影响。研究结果阐明了极低瓦斯浓度对瓦斯爆炸规律的影响，为控制瓦斯爆炸灾害提供了理论支持。随着甲烷浓度从 0 vol 增加而线性增加。% 至 3.0 vol. % 在返回隧道中。增加爆炸性甲烷体积和浓度导致火焰传播距离显着增加。还注意到增加甲烷浓度导致最大超压比线性增加，甲烷体积和浓度均对最大超压比和平均超压上升速率有敏感影响。研究结果阐明了极低瓦斯浓度对瓦斯爆炸规律的影响，为控制瓦斯爆炸灾害提供了理论支持。随着甲烷浓度从 0 vol 增加而线性增加。% 至 3.0 vol. % 在返回隧道中。增加爆炸性甲烷体积和浓度导致火焰传播距离显着增加。还注意到增加甲烷浓度导致最大超压比线性增加，甲烷体积和浓度均对最大超压比和平均超压上升速率有敏感影响。研究结果阐明了极低瓦斯浓度对瓦斯爆炸规律的影响，为控制瓦斯爆炸灾害提供了理论支持。还注意到增加甲烷浓度导致最大超压比线性增加，甲烷体积和浓度均对最大超压比和平均超压上升速率有敏感影响。研究结果阐明了极低瓦斯浓度对瓦斯爆炸规律的影响，为控制瓦斯爆炸灾害提供了理论支持。还注意到增加甲烷浓度导致最大超压比线性增加，甲烷体积和浓度均对最大超压比和平均超压上升速率有敏感影响。研究结果阐明了极低瓦斯浓度对瓦斯爆炸规律的影响，为控制瓦斯爆炸灾害提供了理论支持。