Numerical analysis of the distribution of combustion products from methane explosions in a full-scale tunnel using all-speed CFD code GASFLOW-MPI

ABSTRACT

Methane explosions are among the main hazards in coal mines. Shock waves from methane explosions can cause damage near the explosion site, and combustion products can spread along the tunnel to locations far from the explosion source and endanger the lives and health of personnel. Therefore, the study of the propagation patterns of methane explosion shock waves and the distribution of high-temperature combustion products in tunnels. has significance for emergency decision-making in the event of methane explosions in a mine. This study uses the 3D Computational Fluid Dynamics (CFD) program GASFLOW-MPI, which models the one-step methane combustion mechanism with the addition of a heat transfer model. The methane explosion process is simulated and reproduced at the Lake Lynn Experimental Mine (LLEM) to analyze the process of gas deflagration. The results reveal that the overpressure in the tunnel after the methane explosion oscillates and decays with time. Gaseous products of the explosion “expand and compress” and flow back and forth in accordance with the oscillation of overpressure. The maximum expansion ratio of the CO₂ concentration isosurfaces of 0.5% in the heat transfer simulation is 6.21, whereas the volume expansion ratio is 3.78 once the flow field stabilizes. The distribution of combustion products along the alleyway exhibits a Gaussian decay trend. The range of gaseous product distribution and temperature fields in the adiabatic tunnel is significantly higher than that in the heat transfer simulations, thus indicating that heat loss significantly influences the temperature characteristics and distribution pattern of combustion products in the full-scale tunnel.

KEYWORDS:

• methane explosions
• distribution of combustion products
• full-scale tunnels
• heat transfer
• overpressure
• GASFLOW-MPI

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Author Contributions

Formal analysis and resources L.Y.; writing – review and editing, L.B.; resources, S.S.; resources, X.J. formal analysis M.K.; writing – review T.J. All authors have read and agreed to the published version of the manuscript.

Additional information

Funding

This work was supported by the Liaoning Provincial Natural Science Foundation funding program [grant numbers 2021-KF-23-05] and the basic scientific research business expenses of Central Universities [grant numbers 2022YQAQ09]. Baiwei Lei was also like to acknowledge China Scholarship Council for its financially supported.

Notes on contributors

Yuntao Liang

Yuntao Liang graduated from Zhejiang University in 2010 with a Ph.D. degree. He primarily researches gas explosions, industrial combustible gas explosion safety, the theory and technology of coal mine fire prevention and control, the disaster-causing mechanism of thermo-dynamic compound hazards, and mine emergency rescue. He is currently the General Manager of China Coal Technology and Engineering Group Shenyang Research Institute Co., Ltd., Director of the State Key Laboratory of Coal Mine Safety Technology, a researcher, and a doctoral supervisor.

Baiwei Lei

Baiwei Lei obtained his Ph.D. degree in 2015 from the China University of Mining and Technology (Beijing). His research mainly focuses on the mechanism of fire and explosion evolution, mine ventilation, and mine emergency rescue. He is currently an Associate Professor in the School of Emergency Management and Safety Engineering at China University of Mining and Technology (Beijing).

Shuanglin Song

Shuanglin Song primarily researches coal mine fire monitoring and early warning technology, clean flame-retardant materials, and treatment techniques for hidden coal spontaneous combustion zones. He is currently the Deputy Director of the Experimental Center at China Coal Technology and Engineering Group Shenyang Research Institute Co., Ltd. State Key Laboratory of Coal Mine Safety Technology.

Jianjun Xiao

Jianjun Xiao obtained his Ph.D. degree from Tsinghua University and is primarily involved in scientific research on detonation, turbulent combustion, and multiphase flow. He is currently a Senior Researcher at the Institute of Thermal Technologies and Safety, Karlsruhe Institute of Technology in Germany.

Mike Kuznetsov

Mike Kuznetsov received his Ph.D. degree from the Leningrad Institute of Technology and is primarily engaged in scientific research on detonation, turbulent combustion, and multiphase flow. He is currently a Senior Researcher at the Institute of Thermal Technologies and Safety, Karlsruhe Institute of Technology in Germany.

Thomas Jordan

Thomas Jordan is currently conducting scientific research on detonation, turbulent combustion, and multiphase flow at the Institute of Thermal Technologies and Safety, Karlsruhe Institute of Technology in Germany.