| Blasting is indispensable in the process of underground mining work link, along with the mining more and long time, many mines are in deep mining. The mining depth, the greater the underground environment (such as temperature, humidity, etc.) worse, at the same time, various blasting toxic or harmful gases generated in the working face is becoming more and more difficult to rule out in time. Mining industrial explosive toxic gases mainly for CO and NOx, CO has great harm to human body, serious when can make person suffocate to death. If the smoke is not ruled out in time of blasting fume poisoning accident can lead to work related injuries, and eventually to mine and country brought serious economic loss.In the CFD theory this paper, under the support of a mine in DaYao county as the research object,12kinds of roadway model is established with GAMBIT software, simulates the5kinds of different conditions, the fumes diffusion of the whole law, and expounds the CFD numerical simulation and harmful gas nature and harm of blasting fume generated. In this paper, on the basis of the actual tunnel model, calculated the CO diffusion coefficient of NOx and consider the fumes diffusion process for three dimensional numerical simulation of the blasting in roadway adopting market mainstream CFD software FLUENT after major toxic gas diffusion process by numerical simulation and analysis.In this paper on the diffusion rule before using the FLUENT software to simulate the fumes, studies to determine the three important factors, which affect the fumes diffusion, including ram respectively, and the size of the air quantity, and diameter ram distance of working face. According to the actual situation, the specific research contents and conclusion include:the hydrogen diffusion simulation in the limited space, the fumes turbulent flow numerical simulation, the press in type attached to the wall jet flow field numerical simulation, fumes concentration area migration rule, local fan and duct diameter of tunnel ventilation effect, reasonable pressed air quantity and the linear relation between ventilation time the length of drift. The research results show that the fumes density movement conform to certain rules, by moving from working face to drift mouth; When the drift footage to20m, local fan should be installed in a timely manner; The diameter of the ram and the distance of working face in fumes exclusion process have a certain effect; For pressed ventilation, the reasonable air volume is less than according to the minimum wind speed formula of the calculated value and the practical air volume in mine; Use EXCEL linear fitting out of the mathematical relationship between ventilation time and the length of roadway; With the KJ90NB monitoring and controlling system based on the actual monitoring data verifies the gas concentration changes in general laws; In order to avoid distortion of data, it is suggested that increase the number of CO sensor, and change the installation location; Finally, a numerical simulation for the mine selects the best ventilation scheme, and puts forward related suggestions.In this paper, the research content of mine mining and excavating work has a certain practical significance, and is of great reference to formulate ventilation measures. With the rapid development of CFD simulation technology and efforts to constantly improve the "Six Systems" construction, the research on the problem of fumes diffusion in the future will have greater rigorous, depth and diversity. |
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