| With the increasing of mining scale,the depth of mine mining and the continuous improvement of mechanized level of mining equipment,in particular,the mobile heat source represented by the trackless mobile device causes the exothermic heat of the roadway to increase the local ambient temperature of the roadway,which has become the main cause of the heat damage to the working face.In this paper,using the method of field measurement,experiment and numerical simulation to study the 850 m horizontal working face of Jinchuan second mine,Studying the distribution of temperature field distribution of local roadway when the scraper moves in different directions and at different speeds.The main research methods,research contents and research results of the paper include:(1)Data collection and field measurement of the heat source in the stope of Jinchuan second mine,the analysis and calculation showed that the heat released by the mobile heat source accounts for 48.28% of the total heat dissipation of the stope,which can increase the average temperature of the stope air by 2.68°C.(2)Using the similarity principle to design and set up a downhole fixed heat source test benches,to measure the temperature field distribution of fixed heat source.It is found that the heat source has great influence on the roof of the downwind side of the roadway.(3)The mathematical model of downhole fixed heat source is established and the experimental model is numerically simulated.By comparing the simulation results with the experimental results,the correctness of the mathematical model is verified.(4)Using the existing mathematic model and combining with the dynamic grid technology,the underground moving heat source is simulated and studied.The study found that the movement speed and direction of the heat source have a greater influence on the wind temperature of the stope local.(5)Taking the JCCY-6 model scraper in Jinchuan No.2 Mine as an example,the influence of the moving speed and moving direction of the scraper on the local wind flow temperature in the stope was studied by numerical simulation.It is known that the stope wind speed is 1m/s and the scraper movement speed is 1m/s,2m/s,and 3m/s,respectively.Research results are as follows: When the scraper moves downwind or upwind,the temperature of the air in front of the scraper head changes little,and the temperature at the height of Y=1.75 m at the center section of the rear end of the car at Z=2m is parabolically distributed.When the scraper moves downwind,the highest temperature occurs at about 1.5m from the rear of the vehicle and drops to 26°C at 13 meters.When the scraper moves against the wind,the highest temperature occurs at 1.7m from the rear of the vehicle.The distance is 12 meters.Drop to 26°C.When the scrapers move downwind at speeds of 1m/s,2m/s,and 3m/s respectively,the impact range on the windward side of the stope is increased from 16 meters to 20meters;the scrapers are respectively 1m/s,2m/s,3m/s When the speed of moves against the wind,the influence on the windward side of the stope decrease from 30 meters to 28 meters. |
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