Research On The Transfer Process Of Belt Conveyor Using DEM-FLUENT Combined Simulation

Dust has a variety of hazards,such as damage to the health of workers,causing mine accidents,increasing equipment wear and tear.Belt conveyor is a common transportation equipment,transshipment system is a serious dust production link,for which many enterprises spend a lot of energy and financial resources.Through the analysis of the movement state and characteristics of material flow,air flow and dust,the material flow and dust are regarded as continuous medium and discrete medium respectively,and the mathematical model of material transfer process is established.Using the Euler model of DEM-FLUENT coupling technique and the Discrete Phase Model of FLUENT to calculate and simulate the airflow movement and dust distribution during the transshipment process.The dust suppression ability and influence factors of the transfer system are evaluated and studied.Aiming at a traditional belt conveyor transshipment system,the particle model is established,and the geometric model is established and divided into grids.The movement of airflow and dust in the reproduced system was simulated and analyzed by EDEM and FLUENT software,and the evaluation methodology of dust suppression ability was established.The simulation results of dust concentration and induced air volume are compared with the measured results and the empirical ones,which proves the rationality of the simulation results.The results show that the induced airflow velocity increases gradually with the transfer direction,increasing swirl properly will reduce dust;The simulation results show that the induced air volume is about 535m3/h during the blanking process,and about 3.5%of the new dust escapes from the transfer system to the operating space in the unit time.It's difficult to reduce the static pressure and accelerate the dust settlement by increasing the height of the guide grooves,and other dust suppression measures need to be introduced.Based on DEM-FLUENT coupling technology,the traditional dust suppression and two kinds of balance wind pipe dust suppression schemes are compared and analyzed.Indicating that balance wind pipe dust suppression scheme can reduce the induced wind speed of the transfer point of the conveyor head and the induced air volume at the outlet of the guide groove.It is determined that the dust suppression effect of the balance wind pipe dust suppression with circulating wind pipe and return air pipe is better.By analyzing the reflux strength and induced air volume of the circulating air duct under the diameter of 300mm,400mm and 500mm,determining the suitable diameter of the pipe is 400mm.The DEM-FLUENT combined simulation technique was used to verify the relationship between the induced air volume in the empirical formula and the belt speed,the height of the blanking and the section size of the blanking tube.The effect of belt speed on the induced air volume is the most.Under the premise of high speed and large transport volume,the section size and the drop height of the blanking tube should be minimized.Empirical formula can only describe the change regulation of induced air volume with the belt speed,height of blanking,and cross section area of blanking tube in a certain range.It is not applicable to the calculation of the volume of induced air when the height of the blanking or the cross section of the blanking tube is too large.