Study On The Simulation Of Mine Belt Fire Disaster And The Design Of Automatic Extinguishing System

Most of China's coal mines use flame retardant conveyor belt,but due to the complex environment of coal mine,coal spontaneous combustion,electric sparks,open flames,etc.under certain conditions can still ignite the fire belt.Once the belt of fire,the fire spread rapidly,the fire zone of tunnel adjacent to temperature rises rapidly,producing a large amount of toxic and harmful gases into the air with the downwind side of the mining area,thus threatening the safety of mine workers.Study of mine belt conveyor fire disaster process,master of mine belt conveyor fire quickly and accurately when the tunnel airflow state,temperature distribution,fire smoke spread,to the disaster site command,to protect the safety of mine workers is very important.On this basis,the automatic monitoring of fire extinguishing system design of mine belt conveyor,belt to detect and control the fire,reduce the fire caused by the loss of property,protect the safety of mine workers,has become a serious problem.In this paper,the cause of the fire starting from tape to tape,the study on combustion characteristics of typical fire combustible materials as the starting point,adopting the research method of field sampling analysis,numerical simulation and experimental study on Determination of calculus,in-depth characteristics,belt fire change law and influence factors of water mist extinguishing characteristics of combustion of combustible material fire on tape and,on this basis,combined with the distributed optical fiber temperature measurement technology and water mist fire extinguishing technology,design the automatic fire extinguishing system of distributed optical fiber temperature measurement technology of mine belt conveyor based on water mist,in order to realize the unattended automatic processing of fire.The main research work and achievements are as follows:(1)Analysis of the cause of the fire belt of the mine fire,summarizes the general development law of mine belt fire,according to the fire theory,combustion characteristics of coal mine belt conveyor fire typical combustible materials were cone calorimeter,determined the maximum heat release rate for 138kw/m2 coal,the maximum heat release rate of flame retardant tape is 285kw/m2.Provide reference data for the numerical simulation of mine belt fire.(2)Using the fire dynamics simulation software Pyro Sim,combined with Gaoping incline mine actual situation,create mine belt fire model,based on the combustion characteristics of typical combustible material belt fire experiment to determine the setting model of combustion parameters,simulation of mine belt roadway fire occurs and the flue gas temperature distribution law of belt fire disaster.The results show that the wind speed of the belt fire disaster process is affected when the belt of fire,increasing the wind speed,though the resulting tape burning distance increases,the roadway temperature,but can effectively suppress the fire smoke backflow,reduce toxic gas CO production and spread.(3)Analyze and compare the characteristics of the present automatic fire extinguishing system,study the influence factors of the underground fire extinguishing system,and select the high pressure water mist as the fire extinguishing system.Set the fire belt of high pressure water mist extinguishing model,simulation analysis of the influence of water mist nozzle,setting fire on the performance results show that the nozzle installation height of water mist extinguishing effect process of quadratic function distribution,the optimal installation height of 1m above the belt.Sprinkler and fire the horizontal position of the distance is,the worse is the extinguishing effect,when the horizontal distance is more than 1m,but still lost the basic fire extinguishing performance,has a certain inhibitory effect on the fire.Multi nozzle can effectively enhance the performance of water mist,but the number of nozzles start more than 3,enhance the performance of less water mist can be determined,so the fire belt of high pressure water mist automatic fire extinguishing system is installed as a nozzle at the height of 1m over the tape,22 nozzle interval not more than 1.5m when the belt of fire,should start the fire the upwind side 1 and leeward 2 nozzles,can achieve better extinguishing effect.(4)According to the simulation results,combined with the actual situation,the design of automatic fire extinguishing system of distributed optical fiber temperature measurement technology based on the accurate grasp of fire location,to achieve unattended automatic fast processing of fire.