Research on dust removal technology of large eddy dust collecting and swirl airflow distribution in the fully-mechanized excavation face

Abstract

Aiming at the tricky problem of dust pollution at the fully-mechanized excavation face, the dust removal technology of large eddy dust collecting and swirl airflow distribution was studied. This method divides the space in the tunnel into two air field by airflow distributor. An air-dust coupling model was established to study the law of air field and dust migration. The results show that the upward-tilt angle α and back-tilt angle β of the side outlet of the airflow distributor have a great influence on the formation of reverse swirl airflow. With the increase of α in the range of 20– 35°, the intensity of transverse dust control eddy first increases and then decreases. With the increase of β in the range of 0° ∼ 20°, the dust control effect is enhanced. The back-tilt angle γ of the airflow blown by the end outlet of airflow distributor to the heading face can reduce the air disorder, and the transverse dust control eddy can be formed. Similarity experiments show that the actual dust diffusion distance corresponding to the tracer fog dust is 9.8 m, and the relative error is about 5.1% compared with the simulation results in this paper. With the new technology, the dust removal efficiency is up to 98.3%, and the working environment during the tunneling process will be greatly improved. • A new dust control equipment and strategy was proposed. • The formation mechanism of air curtain were analyzed. • The rules of dust diffusion after using air distributor was obtained.