Study On The Concentration Distribution Of Gas In Heading Face And Optimization Of Duct Arrangement

Gas in coal roadway is one of the main hazards in mine production.Heading in the excavation work,the continuous emission of gas caused by the potential danger and often harmful possibility of the gas accidents and the resulting.Construction ventilation can not only dilute the concentration of pollution in the roadway,but also ensure that the fresh air to ensure the safety of the staff.Therefore,the underground tunnel ventilation is particularly important.Carry out blind tunnel flow field analysis and ventilation layout optimization,has the important practical significance for ensuring the safety of coal mines.Based on the actual coal mine roadway heading face based on the project,the field test,theoretical analysis and numerical simulation methods of heading face ventilation through the research on Simulation and optimization of air duct arrangement,the main achievements were as follows:(1)According to the actual project,this paper completed the on-site test and measurement of heading face simulation area,the basic parameters of the ventilation simulation,and use Fluent to establish a three-dimensional numerical model of the heading face ventilation.(2)Through the software simulation obtained the ventilation flow field and gas concentration distribution in heading face,verify the tunnel airflow field has obvious zoning characteristics.The gas concentration heading and airflow velocity have obvious stratification and uneven distribution of the phenomenon in the section of the roadway,the roadway and the return air side of the gas concentration is greater than the air inlet side of the gas concentration and gas concentration on the roadway high corner and lower right corner of the return side.Therefore,in the aspect of gas prevention of similar projects,not only to strengthen the monitoring of the upper corner,should also return side wall to the top of the wall position of the gas monitoring.(3)The main factors that affect the gas concentration are determined,including the diameter of the air duct,the outlet velocity of the air duct,the distance between the air outlet of the air duct and the working face,and the hanging position of the air duct four.The software simulation and orthogonal test design,and the range of the gray correlation of grey correlation degree to study the influencing factors by influencing factors on gas sensitivity,heading concentration influence and the influence factors of gas concentration,gas concentration on this kind of change has grey correlation inherent law,and ultimately determine and verify the optimal ventilation layout scheme.(4)This paper was established the linear regression prediction model of gas concentration by using multivariate linear regression analysis method,and the parameters were solved and the significance test of the model.By using the statistical software of SPSS to calculate the correlation coefficient and linear fitting equation and the derived Eureqa Pro-Trial software were analyzed to determine the final multivariate linear regression model is more reasonable.