Research On Numerical Simulation Of Regularities Of Dust Distribution Of Front Pumping Back Pressing Hybrid Ventilation In Machine Operating Work Face

In recent years, as a major disease that is harmful to the health of people, occupational pneumoconiosis has been more and more people concerned. Espeically in the coal industry, pneumoconiosis infection problem is particularly prominent. To prevent the occurrence of pneumoconiosis, the most efficiency way is dealing with pollute area from the dust in regional areas, directing dust out of work areas.With mechanize mining increasing, mechanize face is one of the most polluted areas. Practice has proved that, tunneling ventilation in heading face is one of the most effective measures to improve the working environment to ensure safety in production. CFD numerical simulation can accurately grasp the roadway distribution of airflow movement shunt flow field and mass transfer processes.This controls the distribution of the roadway dust and determines a reasonable outlet duct from the head section of roadway distance, pumping air pressure ratio and the impact of roadway in the area of working conditions and reasonable argument.It has an extremely important value to tunnel face gun smoke, dust and other toxic and harmful substances discharged and prevent its accumulation.In this text, studying on front pumping back pressing hybrid ventilation dust control mechanism, in fluid mechanics, aerodynamics, jet theory and other related theories as a basis, using numerical simulation and laboratory model experiment, researched hybrid ventilation and dust control for system integrated from hybrid ventilation air flow structures, dust transport regularity and influence factors and so on:(1)Based on the jet theory and confluence theory,it analysises the free turbulent submerged jet.And by using the attached wall jet,it analysises hybrid ventilation’s air flow structures of mechanize face.(2)In the background of mine roadway’s ventilation system,it using the software FLUENT to establish reduced local tunnel ventilation system physical model,and introducing the disturbance source model to approximately sumilate dust dispersion discipline of the roadway.(3)By using the CFD software FLUENT,it silmulates the multi-parameter of hybrid ventilation of mechanize face. And it uses the phase model model (DPM model) which is provided by FLUENT to simulate the migration of dust in the roadway,which abtains the reasonable working parameters about dust controlling effection in the condions of this way of ventilation.The reasonable working parameters are reasonable air duct mouth and reasonable air volume ratio.At the same time,by chaning the size of the area of the roadway,it furtherly analysises the different cross-sectional area’s reasonable parameters. (4)Base on similarity theory,it establishes a experimental modes about hybrid ventilation under laboratory condions.The numerical simulation’s reasonalbe working parameters are validated by the result of the experiment,and the experimental results are basically consistent with the results of numerical simulation.