Numerical simulation and disaster prevention for catastrophic fire airflow of main air-intake belt roadway in coal mine—A case study

ZHOU Gang(周刚)^{1, 2, 3}, CHENG Wei-min(程卫民)^{1, 2}, ZHANG Rui(张睿)⁴, SHEN Bao-tang(沈宝堂) ³, NIE Wen(聂文)^{1, 2}, ZHANG Lei(张磊)^{1, 2}, WANG Hao(王昊)^{1, 2}

(1. State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and
Ministry of Science and Technology (Shandong University of Science and Technology), Qingdao 266590, China;
2. College of Mining and Safety Engineering, Shandong University of Science and Technology,
Qingdao 266590, China;
3. Energy Flagship, Commonwealth Scientific and Industrial Research Organisation, P.O. Box 883,
Kenmore, Brisbane, QLD 4069, Australia;
4. Gas Research Branch, Chongqing Research Institute of China Coal Technology & Engineering Group
Corporation, Chongqing 400037, China)

Abstract:Coal mine belt fire develops very rapidly and is difficult to control. If not suppressed quickly, a belt fire could easily lead to airflow disorder and undermine the ventilation system. However, belt fire can be prevented effectively by establishing fire airflow control system. In this work, the 5th belt roadway of Kongzhuang coal mine was taken as the object of investigation, where geometrical models of this roadway were established firstly. Then, based on mathematical model of fire smoke flow, the CO volume fraction, smoke density distribution, air temperature and pollutant velocity vector in the roadway before and after taking airflow control measures were simulated by using Fluent software. It can be known from the simulation that with the normal ventilation status in 5th belt roadway, the countercurrent of smoke does not happen when a fire occurs; the roadway’s section is almost filled with CO at 10 m downstream from the fire source, and with air velocity getting stable gradually, the CO concentration reaches about 15 %. After taking airflow control measures, the effect range of temperature field which are harmful to the miners decreases from 69 m to 30 m; and the distance of the roadway fully filled with CO is 5 m farther than that before taking measures. Finally, according to the numerical simulation results and the actual condition of the belt roadway, the warning and automatic remote airflow control system with short-circuit method for the 5th belt roadway was designed to guarantee the safety production.

Key words:belt roadway fire; catastrophic airflow; numerical simulation; flow pattern; early warning and control