Optimization Of Radial Cyclone Shielding Ventilation System In Fully Mechanized Face And Numerical Simulation Of Dust Control

In recent years,the accident rate of coal mines has continued to decrease,but dust disasters have become more prominent.The pneumoconiosis caused by high concentration dust environment and dust explosion accidents seriously threaten the physical and mental health of coal miners.In order to reduce the dust concentration in the main dust-producing area under the coal mine,namely the area of the fully mechanized mining face,the source of dust and the physical and chemical characteristics of the dust are understood.According to the law of dust movement with the wind,the wind flow in the fully mechanized mining face Adjust the flow field.Aiming at the shortcomings of the current ventilation system commonly used in comprehensive excavation working face,based on long pressure short pumping ventilation and attached wall cyclone ventilation,a radial swirl shielding ventilation system for comprehensive excavation working face is designed to control the comprehensive excavation working face The problem of dust diffusion from various dust sources provides a good working environment for coal miners and ensures safe production underground.This article takes the comprehensive excavation face of a coal mine in Baise,Guangxi as the object,and uses Solid Works software to establish a numerical simulation model.Through numerical simulation,the flow field and the dust concentration distribution in the tunnel under the radial cyclone shielded ventilation system were obtained,and the dust control effect of the radial cyclone shielded ventilation system was studied.Preliminary research shows that:Under the radial cyclone shielding ventilation,the dust concentration in the driver's cab area of the roadheader is much lower than the dust concentration in other areas of the comprehensive excavation face;Radial cyclone shielding ventilation in the comprehensive face The system can shield the excavation dust produced at the fully mechanized face and the dust at the transfer point of the roadheader outside the cab of the roadheader to prevent the dust from spreading to the cab of the roadheader.In order to ensure the accuracy of numerical simulation,an experimental platform of radial cyclone shielded ventilation system was built according to 1:10,and the experiment and numerical simulation were connected by the similarity criterion.In the verification experiment,the PIV particle image velocimetry system and dust sampler were used to record the flow field and dust concentration distribution in the tunnel under the radial cyclone shielded ventilation system.The experiment and numerical simulation were compared and analyzed.Validation.In order to make the radial cyclone shielding ventilation system of the comprehensive excavation face obtain better ventilation and dust control effects,the influencing factors of the radial cyclone shielding ventilation system's dust control effect were analyzed,and the radial cyclone shielding ventilation system's dust control effect was found.Mainly affected by the thickness of the air curtain shielding the air curtain,the integrity of the air curtain,and how much the disturbance of the flow field in the area near the air curtain.The numerical simulation method is used to conduct an in-depth study on the structural parameters of the radial swirl shielded ventilation system.The research shows that: In the radial swirl shielded ventilation system,by changing the ratio of the blower to suction volume,the air inlet and the first The system structural parameters such as the distance between the annular slits,the width of the annular slits and the ratio of the air volume of the annular slits can improve the strength of the air curtain of the radial air curtain and effectively improve the dust control effect of the radial cyclone shielding ventilation system;When the air volume ratio of the air cylinder is1.5,the distance between the air inlet and the first annular slit is 0.6 m,the width of the annular slit is 0.09 m,and the ratio of the air volume of the annular slit is 1.4,the radial air curtain The intensity of the air curtain is optimal,and the radial swirl shielded ventilation system can obtain a more ideal dust control effect.