| China's typical resource situation of poor oil,less gas and rich coal determines that coal will remain in the leading position in China's energy structure for a long time.With the continuous development and improvement of science and technology,the mechanization degree of coal mine underground operation is constantly improved,and the dust concentration at the working face is also increased.The increase of dust concentration not only threatens the safety of coal mine production and the physical and mental health of workers,but also seriously restricts the green development strategy of coal mine.How to control the dust concentration has become the focus of daily management.At present,the technology of spray and dustfall is mostly used for dust control.When using this technology,there are some problems,such as improper installation position of nozzle,too small water supply pressure,too large droplet size and so on.In order to solve the above problems,this paper uses the experimental and numerical simulation methods to study the common types of nozzles,in order to select the suitable nozzle and water supply pressure.By means of experiment and numerical simulation,the macro and micro atomization characteristic parameters of the nozzle were measured and analyzed.Based on the analysis of macro atomization characteristic parameters,the nozzle with better performance is selected according to the coupling of flow rate and atomization angle.The nozzle was deeply studied by numerical simulation.According to the relationship between droplet size and droplet velocity and water pressure and distance,the best water supply pressure and nozzle installation position were found.The results show that the optimal droplet size(30?120um)accounts for a large proportion in the range of water supply pressure of 8Mpa and the range of 700mm?1100mm away from the nozzle.At this distance and water supply pressure,the nozzle can effectively control the dust concentration.Figure[34]Table[13]Reference[74]... |
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