Study On Cooling Effect And Thermal Comfort Of Water Injection And Ventilation In Coal And Rock Mass Of Deep Mine

With the development of economy,the use of coal is increasing.The mine inevitably enters deep mining.Heat release from surrounding rock of mine roadway is the leading factor of mine heat damage.The deep rock mass is rich in a large number of voids.When water injection is used to cool down,it will change the temperature distribution of the surrounding rock mass of the roadway,which will affect the wind flow temperature and humidity field in the roadway and affect the underground working environment.Therefore,the research on the surrounding temperature and roadway temperature field of roadway under water injection has important theoretical and practical significance for further revealing the mechanism of flow and heat coupling in deep mines and effectively utilizing mine water injection and cooling technology.Based on the research of deep mine cooling and underground thermal environment at home and abroad,the surrounding rock mass temperature is analyzed of the mine during water injection and changes in the temperature and humidity of the air in the roadway.The project starts from the distribution law of deep geothermal field,and takes the coupling mechanism of mine water injection,rock mass and wind flow temperature field as the breakthrough point.The theoretical analysis and numerical simulation method are used to systematically study the mechanism of water injection cooling in deep mines.The surrounding rock mass model under the action of water injection was established,and the temperature field distribution of the surrounding rock mass of the mine roadway under water injection was studied.The UDF programming was used to analyze the roadway under different working conditions based on the temperature of the summer heat transfer ring at980m in Sanhejian Mine.The change of air temperature and humidity;analyze the influence of long-pressure long-type ventilation on the temperature field of roadway,and use MATLAB to analyze the variation of wind speed and temperature on human skin surface temperature under different ventilation modes;Under the circumstances,comprehensive analysis of the impact of deep mines on the temperature field of the roadway and human thermal comfort in the environment of water injection and ventilation,and a better method of water injection and cooling.The results show that the water injection speed,water injection distance and the distribution form of the water injection port have an important influence on the temperature and humidity field of the roadway.When long-pressure and long-exhaust ventilation mode,intake duct and exhaust duct are located on both sides of the roadway,10m from the intake pipe to the heading face,the exhaust pipe mouth is located 2m away from the heading face8.3 m~3/s for air supply and 7.0 m~3/s for air extraction,and 293 K for air supply,when the water injection speed exceeds 1.0 m/s,the influence on the environment temperature and skin temperature of the roadway is slight;the appropriate water injection parameters are determined as follows:the water injection speed is 1.0m/s,the water injection distance is5m,and the water injection port is misplaced.The ambient temperature of the roadway working area is about 23°C,and the surface temperature of the human body is between33°C and 34°C,which meets the requirements of the deep mine environment temperature and meets the human thermal comfort requirements.