Numerical Simulation of the Dust Suppression with Forced Ventilation Shunt Mode in Fully Mechanized Workface

Based on fluid mechanics, the theory of gas-solid flow and jet theory etc. Dust migration regularity in fully mechanized workface was studied and simulated under far-pressing-near-suction ventilation with FLUENT Simulation technology. When the ratio of blowing to suction (μ) is larger than 1, the range of high dust concentration reduces and the maximum dust concentration decreases. The sketch of flow field of the different μ, the short of traditional far-pressing-near-suction ventilation and the superiority in practical of dust removal mode with the forced ventilation shunt were summarized and analyzed. The dust migration regularity in different shunt parameters (K) in this mode was simulated. Increasing shunted air quantities (Q) is beneficial to the control of dust diffusion in the roadway. But dust concentration near pressure air side will increase if the value of the shunted air quantities is over a critical value.

Download Full-text

Experimental Research and Numerical Simulation of Ejector Precipitator in a Fully Mechanized Mining Face

Arabian Journal for Science and Engineering ◽

10.1007/s13369-020-04937-1 ◽

2020 ◽

Vol 45 (11) ◽

pp. 9815-9833

Author(s):

Guodong Zhai ◽

Wentao Zhang ◽

Yaozong Li ◽

Xinghao Lu ◽

Wenyuan Hu

Keyword(s):

Numerical Simulation ◽

Flow Field ◽

Negative Pressure ◽

Coal Dust ◽

Structural Parameters ◽

Dust Concentration ◽

Dust Removal ◽

Measuring Point ◽

Mining Face ◽

Supply Water

AbstractIn order to effectively reduce the coal dust concentration in a fully mechanized mining face, this research used laboratory experiment, numerical simulation, and field test to conduct an in-depth exploration of the ejector precipitator installed at the low-level caving coal hydraulic support. Firstly, through the experimental platform in the laboratory, the dust removal effect of the nozzle with different structural parameters was tested, and the 3D particle dynamic analyzer was adopted to verify its atomization characteristics; then, the structural parameters corresponding to the nozzle in the best test results were obtained. Secondly, by using Fluent, the negative pressure flow field in the ejector barrel was numerically simulated. The results indicated that when the pressure of supply water was 12 MPa, the negative pressure value formed in the flow field was the lowest and the inspiratory velocity was the largest, which was conducive to dust removal. Finally, the tests of liquid–gas ratio and dust removal ratio were carried out in a fully mechanized mining face. The results showed that when the nozzle specification recommended by the experiment and the pressure of supply water recommended by the numerical simulation were used, the removal ratios of the total coal dust and the respirable coal dust were 89.5% and 91.0%, respectively, at the measuring point of the highest coal dust concentration. It indicates that the ejector precipitator has a good application effect in reducing the coal dust concentration in a fully mechanized mining face and improving the work environment of coal mine workers.

Download Full-text