Citation

Liu J, Zhou H, Wang W, Zhang Y, Zhao H. China Saf. Sci. J. 2022; 32(12): 79-87.

Copyright

(Copyright © 2022, China Occupational Safety and Health Association, Publisher Gai Xue bao)

DOI

10.16265/j.cnki.issn1003-3033.2022.12.0110

PMID

unavailable

Abstract

In order to explore the air flow field distribution and CO migration characteristics in a spiral construction tunnel on the plateau and improve the ambient air quality of the excavation face in the construction tunnel, Ansys Fluent was used for fluid simulation based on fluid governing equations and component transport models. The characteristics of the airflow field and CO distribution under multiple working conditions were simulated by taking the air speed of supply wind and the distance between the excavation face and air duct as the influencing factors, and a multiple linear regression model was established for the calculation of CO mass concentration in the spiral construction tunnel on the plateau. The results show that the average wind speed of the cross⁃section first increases and then decreases in front of the air duct, and gradually becomes stable behind the air duct along the tunnel exit direction. When the distance between the excavation face and the air duct exceeds 30 m, the two regions of the jet end and the front of the air duct mouth are easy to form an obvious vortex. The CO concentration presents two distribution characteristics: "low in the middle, high on both sides" and "low on the left and high on the right, low on the top and high on the bottom" with the influence of wind speed and distance. The CO mass concentration at different times and sections in the tunnel can be calculated by multiple linear regression model. © 2022 China Safety Science Journal. All rights reserved.

Language: zh