Numerical Simulation Research On Parameter Optimization Of Air Dust Control System Of Fully Mechanized Face

Dust is one of the five major disasters in the normal production of coal mine.It has always been a threat to the health of coal mine workers and the safety and efficient production of coal mines.Therefore,one of the key tasks of coal mine management is to take a variety of effective measures to reduce the dust concentration in coal mines.In this study,taking the comprehensive tunneling roadway driven by the comprehensive excavator as an example,a method for collecting and removing dust by installing a cyclone air curtain with a wall attached to the wind is proposed,which mainly uses a combination of theoretical research and numerical simulation.Methods The effects of dust control and dust removal on the wall-attached fan were studied.First,the mathematical and physical models of the dust-gas two-phase flow are theoretically analyzed,and the k-? free flow field equation based on the turbulence intensity and dissipation rate based on the NS equation is established to analyze the dust in the flow field.Force conditions,establish a discrete phase equation based on the balance of dust particles in the Lagrange coordinate system,and determine the solution conditions;then establish a "solid-gas" two-phase flow model in ANSYS FLUENT to solve the steady state solution.Working flour dust movement status and dust concentration distribution;Finally,the effect of different parameters on the dust control effect is compared by the control variable method.The simulation results show that:(1)At the working position of the driver of the comprehensive excavator,a wind wall is formed due to the effect of the attached air cylinder forming a swirling air curtain,which shields the dust in front of the driver of the roadheader and avoids a large amount of dust.The diffusion at the driver's place,compared with before the installation of the attached air duct,the swirling air curtain generated by the attached air duct can better control the dust concentration in the roadway;(2)After installing the attached air duct,The dust concentration at the driver of the excavator is significantly lower than that when the wall-mounted fan is not installed,and a large amount of dust can be controlled at the head-on position,and it is extracted by the fan;(3)The control variable method is used in numerical simulation,That is,when the other parameters of the comprehensive tunnel are unchanged,change the distance from the slit of the wall-mounted air duct to the head,the size of the slit of the wall-mounted air duct and the pressure extraction ratio,the dust removal effect will also change accordingly.By comparing and analyzing the results of numerical simulation,the best parameters of the dust control system are finally obtained,that is,when the slit of the attached duct is 13 m away from the head,the slit size of the attached duct is 0.8m×0.05 m and the long pressure When the pressure extraction ratio of short extraction ventilation is 1,the dust removal effect of the comprehensive tunnel is best.